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Changelog🔗

All notable changes to RSigma are documented in this file. Each entry corresponds to a GitHub Release.

[Unreleased]🔗

backend convert: per-rule file output when --output is a directory (#205)🔗

rsigma backend convert can now write one file per converted rule instead of a single concatenated stream. When --output points at a directory (an existing directory, or a path with a trailing separator that is created on demand), each rule is written to its own file named after a snake_case slug of the rule title, with the backend's native extension. This was prompted by Fibratus rule-deployment ergonomics: the engine loads one YAML rule per file from its Rules/ directory, so the split output drops straight in without hand-separating the ----joined stream.

  • Naming. File stems are a slug of the rule title (Detect Whoami becomes detect_whoami), falling back to the rule id and then a rule literal when the title slugifies to nothing. Colliding names get a numeric suffix (same.yml, same_2.yml) so two rules never overwrite each other. A rule that converts to several documents (for example a temporal correlation expanded with -O temporal_permute=true) keeps them together in its one file, finalized through the backend so the format-aware separators land inside.
  • Extensions. A new Backend::output_file_extension hook picks the per-rule extension: yml for the Fibratus YAML envelope (txt for its bare-expression expr format), sql for PostgreSQL, and txt by default. Single-file and stdout output are unchanged.
  • Docs. The Fibratus backend reference, the rule-conversion guide, and the README document the directory-output workflow (rsigma backend convert rules/ -t fibratus -p fibratus_windows -o ./Rules/).

Fibratus conversion: corrected field mappings and registry event scoping (#202)🔗

Three correctness fixes to the fibratus_windows pipeline shipped in #191, found while converting more of the upstream Fibratus rules library.

  • Process field coverage. process_creation and process_termination gain the field mappings they were missing against the Fibratus 3.0.0 vocabulary: OriginalFileName -> ps.pe.file.name, CurrentDirectory -> ps.cwd, ProcessGuid -> ps.uuid, ParentProcessGuid -> ps.parent.uuid, IntegrityLevel -> ps.token.integrity_level, Company -> ps.pe.company, Description -> ps.pe.description, Product -> ps.pe.product, and FileVersion -> process.pe.file.version. process_termination additionally picks up the CommandLine, User, LogonId, and Parent* mappings it previously lacked entirely, so a process-exit rule that touches any of those fields now converts instead of failing.
  • Thread events. create_remote_thread maps TargetImage -> evt.arg[exe], so a rule that scopes the injected-into process converts rather than dropping the field.
  • Registry event scoping. The registry_event logsource category now prepends an evt.category = 'registry' discriminator as its first condition, the same treatment the other categories already get. Fibratus rejects a rule at load time when it has no event-type scoping by name or category, so without this the converted registry_event rules would not load.

rstix: Phase 2 slice 1 — model skeleton and common properties🔗

Phase 2 (Data Model + Serialization) begins with slice 1 of ~7. This slice is not releasable on its own.

  • model module: ModelError and model::common property containers — SdoSroCommonProps (required spec_version, created, modified; confidence as Option<Confidence>), ScoCommonProps (SCO-only fields), ExternalReference (STIX §2.5.2: non-empty source_name plus at least one of description, url, or external_id enforced on construction and deserialization), GranularMarking (marking_ref XOR lang; non-empty selectors), and ExtensionMap / ExtensionType.
  • Leaf-type serde: serde_impls/ for StixId, timestamps, and Confidence; typed-ID serde in the define_typed_id! macro; inline LanguageTag serde.
  • Tests: fixture-backed integration tests in tests/spec.rs (tests/fixtures/spec/common/); core serde unit tests in src/core/.

Configurable correlation state caps: --max-state-entries and a new per-group entry cap (#200)🔗

The correlation engine's memory bounds are now fully operator-configurable. Previously the global (correlation, group-key) entry cap (max_state_entries, default 100,000) was a library-only setting with no CLI surface, and nothing bounded the growth of a single group's window state, which grows with timespan x event rate on chatty groups.

  • --max-state-entries <N> on engine eval and engine daemon (config key daemon.correlation.max_state_entries) exposes the existing global hard cap. When reached, the stalest entries are evicted down to 90% capacity and a warning is logged, as before. A drift-guard test pins the CLI default to the engine's CorrelationConfig default across the two crates.
  • --max-group-entries <N> (config key daemon.correlation.max_group_entries, per-rule rsigma.max_group_entries custom attribute) is a new, opt-in cap on retained entries within a single group's window state: timestamps for event_count, (timestamp, value) pairs for value_count and the numeric aggregations, and per-referenced-rule hits for the temporal types. On overflow the oldest entries are dropped, which can only under-count (aggregates saturate; a correlation that needed the evicted entries may not fire). Session windows always keep their oldest entry as the span anchor, so truncation cannot silently extend the timespan cap. Unset means unbounded, the historical behavior, so existing deployments are unaffected.
  • API. CorrelationConfig gains max_group_entries: Option<usize>, CompiledCorrelation gains the matching per-rule override, and WindowState gains truncate_oldest(cap, preserve_front). The per-rule attribute follows the same resolution order as the other rsigma.* correlation attributes: rule override wins over the engine default.
  • Docs. New flags documented on the engine eval and engine daemon CLI pages, the configuration file reference, the custom-attributes reference, the processing-pipelines attribute table, and the Performance Tuning guide's correlation-memory section (which also now states that the global cap bounds group count, not bytes within a group, and is global rather than per-rule).

Correlation window-mode benchmarks: throughput and peak-memory stress suite (#199)🔗

Two new benchmark surfaces for the correlation window modes shipped in #192, prompted by the SEP #214 discussion on memory becoming the bottleneck in stateful window correlation (high-cardinality group keys, long-lived sessions).

  • correlation_window_modes Criterion group (cargo bench -p rsigma-eval --bench correlation -- correlation_window_modes): sliding vs tumbling vs session on an identical event_count workload. All three modes run at ~1.4-1.5 Melem/s — the window decision in apply_window_open is O(1), so declaring window: session is free at evaluation time.
  • correlation_memory bench target (cargo bench -p rsigma-eval --bench correlation_memory): not a Criterion suite — it installs a counting global allocator and reports peak/settled heap deltas, which Criterion cannot observe. Three scenario families: high-cardinality session keys against the max_state_entries cap (1M unique keys held to a 39.8 MiB peak by stalest-first eviction; ~256 B per live session group uncapped), long-lived chatty sessions (8 B per in-window event_count event; value_count with distinct strings costs ~92 B per event and drops to 63 Kelem/s at 1,800 distinct values per window because the distinct count is recomputed per event), and a three-mode comparison on identical load (identical memory and throughput).
  • Documentation: results recorded in BENCHMARKS.md (new Window Modes and Window-Mode Memory Stress sections plus Key Observations); the Performance Tuning guide's correlation-memory section now documents what the cap does and does not bound, per-event state costs by correlation type, the value_count distinct-count hot spot, and the cardinality-flood eviction caveat — and fixes a long-standing inaccuracy (the max_state_entries cap is global across all correlation rules, not per rule). The streaming-detection guide links the window-mode semantics to the measured numbers, and the developer testing guide documents the non-Criterion bench target.

Dependency and security bumps (#206)🔗

Rolls up six open Dependabot PRs into a single merge and patches three RustSec advisories. Rust (workspace Cargo.lock), batched via the patch-updates group (#197): log 0.4.30 to 0.4.32, chrono 0.4.44 to 0.4.45, daachorse 3.0.0 to 3.0.1, async-nats 0.49.0 to 0.49.1, hyper 1.10.0 to 1.10.1, and uuid 1.23.1 to 1.23.2; libfuzzer-sys 0.4.12 to 0.4.13 in fuzz/Cargo.lock (#195). CI (all repinned by commit SHA, batched via the actions-updates group, #198): actions/checkout v6.0.2 to v6.0.3, github/codeql-action v4.36.0 to v4.36.2, and taiki-e/install-action v2.79.12 to v2.81.4. VS Code extension: vscode-languageclient 9.0.1 to 10.0.0 (#196), @vscode/vsce 3.9.1 to 3.9.2 (#194), and esbuild 0.28.0 to 0.28.1 (#203); the three all touched editors/vscode/package.json and package-lock.json, resolved by keeping the newest of each and regenerating the lockfile. Security: the transitive PostgreSQL client stack pulled in through rsigma-convert moves postgres-protocol 0.6.11 to 0.6.12 and postgres-types 0.2.13 to 0.2.14 (RUSTSEC-2026-0179, RUSTSEC-2026-0180) and tokio-postgres 0.7.17 to 0.7.18 (RUSTSEC-2026-0178), closing the three denial-of-service advisories published 2026-06-12.

0.15.0 - 2026-06-11🔗

TL;DR RSigma v0.15.0 is the "new conversion target and Sigma extensions" release: * Fibratus conversion backend: convert Sigma rules into Fibratus rule YAML for the first endpoint-sensor target, with a fibratus_windows field-mapping pipeline, idiomatic macro recognition, ATT&CK label flattening, and sequence-DSL correlation lowering (#191). * Array matching: [any]/[all]/[all_or_empty]/[none] object-scope blocks, implicit any-member matching, and positional indexing (args[0], negative indices), evaluated in the engine and lowered to PostgreSQL JSONB (#159). * Declarable correlation window modes: sliding/tumbling/session windows plus a session gap, end to end across the parser, runtime evaluator, and PostgreSQL conversion, with pySigma-style correlation_method selection at convert time (#192). * sigma-version: an optional top-level spec-major attribute that gates breaking spec changes by the declared version (array matching now activates only at major 3), plus cross-document reference lints (#188). * rstix: a new STIX 2.1 + TAXII 2.1 library crate; Phase 1 lands the core foundation (validated typed IDs, timestamps, deterministic SCO IDs, controlled vocabularies) (#185), thanks to @SecurityEnthusiast. * Gated match-detail enrichment: a new MatchDetailLevel (off/summary/full) that explains why each field matched, off by default so the default wire shape is byte-for-byte unchanged (#186). * RFC 5424 syslog now strips a leading UTF-8 BOM by default, fixing corrupted _raw fields, broken anchored matchers, and BOM-blocked embedded-JSON detection (#187). * Daemon shutdown fix: SIGINT/SIGTERM handlers are now installed before the API listener is announced, closing a startup race that could hard-kill the process instead of draining cleanly.

Fixed🔗

  • Daemon startup signal race. The daemon now installs its SIGINT/SIGTERM handlers eagerly, before the API listener is announced and reachable, and reuses those same streams for the serve task's graceful shutdown. Previously the handlers were installed lazily on the serve task's first poll, so a signal arriving in the window between the socket becoming connectable (the kernel completes handshakes from the listen backlog) and that first poll hit the default disposition and killed the process instead of draining cleanly.

Fibratus conversion backend (#191)🔗

Convert Sigma rules into rule YAML for Fibratus, an Apache-2.0 kernel-event detection and EDR engine. Fibratus is the first conversion target aimed at an endpoint sensor rather than a centralized log store; rules emitted by rsigma backend convert -t fibratus drop into a Fibratus installation's Rules/ directory and load with the same parser as the upstream rules library.

Output formats. Four format names cover two output shapes. default (alias yaml, rule) emits a complete YAML rule document per Sigma rule (name, id, description, labels, condition, min-engine-version, optional action) with --- separators between multi-rule output so the whole stream is a valid YAML document set. expr strips the envelope and emits the bare filter expression only, for piping into ad-hoc Fibratus commands.

Modifier coverage. Sigma's case-insensitive default flips to Fibratus's case-insensitive operators (icontains/istartswith/iendswith); the |cased modifier or -O case_sensitive=true flips to the bare forms. Plain literal equality (no wildcards) uses the dedicated string-equality operators ~= (case-insensitive default) and = (|cased) rather than a wildcard match, which evaluates more efficiently and reads the way the upstream rules library writes literal equality; the evt.name event discriminator always uses the exact =. Wildcard-bearing values lower to imatches/matches. Multi-value OR lists collapse into a single Fibratus list-operator clause (field iin ('a', 'b'), field imatches ('a*', 'b?'), field icontains ('a', 'b'), ...); a |all list stays AND-joined because a list right-hand side is OR-only. Regex (|re) lowers to the regex(field, 'pat1', 'pat2', ...) = true filter function, with multi-value lists collapsing into a single call and negation expressed as a leading not; patterns that use lookarounds or backreferences are rejected with a structured UnsupportedModifier rather than emitting something Fibratus's RE2 engine would reject at load time. CIDR (|cidr) lowers to cidr_contains(field, '...'), with multi-value lists collapsing into a single variadic call. Numeric comparisons map to </<=/>/>=. exists lowers to field != false / field = false and a null value to field = '' (Fibratus has no null token). Field references are native (field1 = field2). Keywords return UnsupportedKeyword because Sigma keywords have no bound field and Fibratus operators require one.

Field naming. A new fibratus_windows builtin pipeline (registered alongside ecs_windows and sysmon) maps Sigma's PascalCase Windows fields to the lowercase-dotted Fibratus vocabulary and adds the right evt.name discriminator per logsource category (process_creation -> CreateProcess, network_connection -> Connect, dns_query -> QueryDns, registry_set -> RegSetValue, ...). Most categories map Image -> ps.exe, CommandLine -> ps.cmdline, TargetFilename -> file.path, TargetObject -> registry.path, DestinationIp -> net.dip, ImageLoaded -> module.path, QueryName -> dns.name. Field names target the Fibratus 3.0.0 registry: DNS fields live under dns.*, loaded executables/DLLs under module.* (the legacy image.* namespace is deprecated), and Sigma fields with no 3.0.0 equivalent (SignatureStatus/Hashes/Imphash under image_load/driver_load, DestinationHostname/Initiated under network_connection) are intentionally unmapped so a dependent rule fails conversion instead of emitting a field the loader rejects. The evt.name discriminator is injected as the first condition (the new add_condition prepend: true option), so the emitted rule leads with the cheapest, most selective predicate and Fibratus short-circuits before the rule body. On a Fibratus 3.0.0 process_creation (CreateProcess) event ps.* is the created (child) process, so Image/CommandLine/ProcessId/User -> ps.exe/ps.cmdline/ps.pid/ps.username and the spawning process is ParentImage/ParentCommandLine/ParentProcessId -> ps.parent.exe/ps.parent.cmdline/ps.parent.pid (Fibratus 3.0.0 decommissioned the legacy ps.sibling.* namespace and unified process attributes under ps.*). For process_access (OpenProcess) the caller is ps.* and the opened process is exposed as event arguments, so TargetImage/TargetProcessId -> evt.arg[exe]/evt.arg[pid] (matching the upstream LSASS-access rule) and GrantedAccess -> ps.access.mask.names. file_event (file creation) excludes the OPEN disposition (the create_file macro semantics) so it does not fire on plain file access, and registry_set/registry_event map Details -> registry.data. The pipe_created logsource is intentionally not mapped because Fibratus has no named-pipe visibility without a kernel driver. Use it whenever you convert SigmaHQ Windows rules: rsigma backend convert rules/windows/ -t fibratus -p fibratus_windows. ATT&CK tags in tags: flatten into Fibratus's labels: block via a static MITRE lookup: attack.<tactic_short_name> -> tactic.id/tactic.name/tactic.ref, attack.t<NNNN> -> technique.id/technique.ref, and attack.t<NNNN>.<sub> -> subtechnique.id/subtechnique.ref (the base technique and sub-technique live in separate label namespaces matching the upstream Fibratus rules library convention). Unknown tags pass through as tag.<original>: <original>.

Correlation. Sigma correlation rules lower to Fibratus's inline sequence ... maxspan ... by <fields> | stage | | stage | DSL (the form Fibratus 1.10 introduced when it decommissioned policy: sequence). The group-by fields, shared across every referenced rule, are emitted once as a sequence-level by field1, field2, ... clause (the upstream rules-library style) instead of repeated per stage, so multi-field group-by needs no inline bindings. temporal_ordered and temporal (ordered fallback) emit one |...| stage per referenced rule; small-threshold event_count and value_count expand into N repeated or N distinct stages capped at -O max_repeated_slots (default 5), with value_count distinctness expressed via positional pattern bindings (field != $1.field and field != $2.field and ...). The four math-aggregate types (value_sum, value_avg, value_percentile, value_median), thresholds above the cap, range/equality predicates, and multi-rule event_count/value_count all return UnsupportedCorrelation with structured rationales the operator can act on; the coverage matrix in the new Fibratus backend reference is the source of truth.

Backend options. -O action=kill,isolate appends an action: block to every rule envelope. -O min_engine=3.0.0 sets min-engine-version:. -O emit_metadata=false drops the description: and labels: blocks for a minimal envelope. -O max_repeated_slots=N raises the correlation cap. -O case_sensitive=true forces the bare operators globally. -O temporal_permute=true expands a temporal (any-order) correlation into one ordered sequence document per permutation of the referenced rules (capped at N <= 3, so 1/2/6 documents per correlation; each permutation gets distinct title and id suffixes), so any matching order alerts; larger correlations return UnsupportedCorrelation. -O use_macros (default true) walks top-level and clauses and replaces recognized runs with idiomatic Fibratus macro calls (spawn_process, create_thread, write_file, read_file, open_file, create_file, set_value, open_process, open_thread, ...), greedy-longest-match so a full three-clause open_file triple beats the standalone evt.name = 'CreateFile' prefix; each clause is matched against both the exact (=) and case-insensitive (~=) operator forms, so recognition is independent of -O case_sensitive, and clauses that match no macro pass through verbatim.

Correlation window modes. The backend honors the rsigma.window / rsigma.gap extension attributes the Correlation window modes entry above adds. The native sequence ... maxspan DSL is itself a sliding total-span constraint per stage, so rsigma.window: sliding (the default) is a faithful pass-through and adds no warnings. rsigma.window: tumbling returns UnsupportedCorrelation because Fibratus has no calendar-aligned bucket primitive. rsigma.window: session (the SEP's "should warn" degraded case) still emits a sliding sequence with the rule's timespan as maxspan, but pushes a warning to the conversion warnings channel noting that the requested per-step rsigma.gap is not enforced because Fibratus has no maxpause-style inactivity timeout. Two new -O options: correlation_method (sliding/session; pySigma-style override that takes precedence over the rule's own rsigma.window) and gap (default session gap for rules that do not declare their own rsigma.gap, used in the warning text). The backend advertises these via the new Backend::correlation_methods and Backend::default_correlation_method trait methods; tumbling is intentionally absent from the advertised list and a -O correlation_method=tumbling override is rejected up-front.

CLI integration. rsigma backend targets and rsigma backend formats fibratus list the new target and its formats. The CLI's per-rule output joining now defers to the backend's finalize_output, which fixes a latent bug for PostgreSQL's view/continuous_aggregate formats (they wanted ;\n\n between statements but got \n) and is what makes the Fibratus --- document separator land correctly on stdout.

Correlation window modes: declarable sliding/tumbling/session windows and a session gap (#192)🔗

rsigma correlation rules can now declare how their timespan is anchored to the event stream, via an optional window attribute, plus a gap field for dynamic session windows, end to end across the parser, runtime evaluator, and PostgreSQL conversion. This is an rsigma-specific extension: a portable-spec version was proposed upstream and declined (sigma-specification #214), on the grounds that the window strategy is a backend-and-deployment concern rather than portable detection logic. rsigma keeps the capability where it is reliable (a stateful streaming engine has no global transaction caps) and follows the upstream guidance: rule-level window/gap live in the rsigma.* extension namespace, and conversion exposes the choice to the converting user the way pySigma's correlation_methods do.

  • New window attribute with three values: sliding (the default, equal to today's trailing per-event window, so no existing rule changes meaning), tumbling (fixed, boundary-aligned, non-overlapping buckets of size timespan), and session (a dynamic window that extends while consecutive in-group events stay within gap, capped by timespan as the maximum total span).
  • New gap attribute reusing the existing timespan grammar (Xs/Xm/Xh/Xd/Xw/XM/Xy). It is required when window: session and rejected for the other modes. The parser errors on a session window without a gap, a gap without a session window, and an unknown window mode.
  • rsigma.* extension namespace. window/gap are accepted both via the rsigma.* engine-extension keys (rsigma.window, rsigma.gap, alongside rsigma.suppress and friends), which is the primary spelling, and via the first-class correlation.window/correlation.gap keys, kept as aliases. The rsigma.* spelling wins when both are present. The parser and linter resolve either spelling.
  • Conversion method selection (pySigma-style). The Backend trait gains correlation_methods and default_correlation_method. The PostgreSQL backend advertises sliding/tumbling/session (default sliding), and rsigma backend convert -O correlation_method=NAME lets the converting user pick the strategy per backend, overriding a rule's own window hint for that conversion. -O gap=5m supplies the default session gap for rules that declare none (a rule's own gap always wins), so correlation_method=session works across whole rulesets. Invalid methods and malformed gaps are rejected both up front in the CLI and per-rule in the backend; rsigma backend formats <target> lists the available methods.
  • Runtime evaluation. The correlation engine honors all three modes: sliding keeps the existing trailing per-event window, tumbling resets per-group state on epoch-aligned bucket boundaries, and session keeps a window open while consecutive in-group events stay within gap, restarting after a gap of inactivity or once the total span would exceed timespan. A late arrival belonging to an earlier tumbling bucket is discarded rather than allowed to reset the active bucket, so out-of-order stragglers cannot wipe an accumulating count. Engine-level state eviction is window-mode aware: sliding state trims by the trailing cutoff as before, while tumbling/session groups are only dropped whole once stale (trimming their front would forget the bucket/session start and silently weaken the timespan cap). The same window logic applies to chained correlations and to event-inclusion buffers. Window bookkeeping is derived from the existing per-group timestamps, so persisted daemon state (snapshots) stays format-compatible and survives upgrades.
  • PostgreSQL conversion. The backend renders the windowing strategy from the rule's window: tumbling emits boundary-aligned buckets (time_bucket on TimescaleDB, date_bin on plain PostgreSQL) sized to the rule's timespan, and session emits a gaps-and-islands query (LAG + a running session id) that honors the gap exactly and enforces the timespan cap as a post-aggregation filter (recorded as a warning). An absent or sliding window keeps the existing per-output_format SQL unchanged, so no existing query changes. Tumbling and session cover every correlation type, including temporal/temporal_ordered, which bucket or sessionize the combined detections and count distinct referenced rules (order is not enforced, matching the existing temporal path).
  • Conversion warnings channel. ConversionResult gains a warnings field and Backend::convert_correlation_rule_with_warnings, so a backend can emit non-fatal "should warn" diagnostics (the closest faithful approximation) while still converting, distinct from a hard ConvertError. rsigma backend convert prints these to stderr.
  • Lint rules. Four new checks: invalid_window_mode, missing_session_gap, gap_without_session, and invalid_gap_format. Both the parser and the linter treat a window/gap key set to a non-string value (e.g. an unquoted gap: 300) as a type error with a quoting hint, rather than silently reading it as absent. The lint catalogue now lists 74 built-in checks plus the 1 reserved enum value (empty_filter_rules).
  • API. rsigma-parser gains a WindowMode enum (Sliding/Tumbling/Session, default Sliding) and window: WindowMode plus gap: Option<Timespan> fields on CorrelationRule, populated from either the rsigma.* or the first-class spelling. rsigma-eval adds window_mode and gap_secs to CompiledCorrelation and an apply_window_open helper. rsigma-convert adds the warnings channel described above plus Backend::correlation_methods/default_correlation_method and correlation_method/gap options on PostgresBackend. The LSP offers a new correlation-session snippet that emits the primary rsigma.window/rsigma.gap spelling.
  • Backward compatible. window is optional and defaults to sliding; gap is only valid under window: session. No existing rule changes meaning or becomes invalid.

sigma-version: gate breaking spec changes by the declared specification major (#188)🔗

rsigma now reads an optional top-level sigma-version attribute on a Sigma document: the Sigma specification MAJOR version the document targets (for example sigma-version: 3). It is the reference implementation of the rule-level spec-version mechanism proposed as SEP #213, split out of array matching so that every future breaking spec change is gated by one declared version rather than a per-feature escape.

  • Fixed-floor default. When sigma-version is absent, the document resolves to a fixed floor (major 2, the v2.x line): a constant defined by the specification, not the latest version the tool supports. Existing rules keep their current semantics and are never silently reinterpreted. Only the major is significant (a release string like "2.1.0" is accepted and read for its major), since breaking changes occur only at major bumps.
  • Array matching is now gated. Array-matching bracket selectors (field[any], args[0], ...) are active only at major 3 or higher. A rule that declares sigma-version: 3 reads a trailing [...] as an array selector; at the floor (absent or major 2) brackets are literal field-name characters, normalized to the escaped form (args\[0\]) so the escape-aware evaluator and converters resolve them literally. This is a behavior change to the (unreleased) always-on array matching, with no compatibility cost because the feature has not shipped.
  • Lint rules. unsupported_sigma_version (error) flags a declared major newer than this build implements; array_matching_without_version (warning) flags a document that uses bracket-selector syntax but resolves below major 3, where the brackets would be read literally rather than as selectors. The linter also resolves cross-document references by id or name, across a whole directory: sigma_version_mismatch (warning) flags a correlation/filter and a rule it references that declare different majors, and unknown_rule_reference (warning) flags a correlation.rules or filter.rules entry that resolves to no rule in the linted set (directory scope only, where the index is complete). Directory linting now runs a two-pass index so references resolve across sibling files. The lint catalogue now lists 70 built-in checks plus the 1 reserved enum value (empty_filter_rules).
  • API. rsigma-parser gains a version module (SPEC_VERSION_FLOOR, SPEC_VERSION_ARRAY_MATCHING, SPEC_VERSION_SUPPORTED, resolve_major, array_matching_enabled, is_unsupported), an optional sigma_version: Option<u32> field on SigmaRule, CorrelationRule, and FilterRule, and a fieldpath::escape_brackets helper. Gating happens at parse time, so the evaluator and converters consume the already-gated AST with no version logic of their own.

Array matching: [any]/[all]/[all_or_empty]/[none] blocks, implicit any-member, and positional indexing (#159)🔗

rsigma can now match members of arrays in event data, an experimental extension proposed to the Sigma specification and accepted as a Sigma Enhancement Proposal (issue #158, sigma-specification Discussion #106, SEP #212). Arrays are first-class in cloud and audit logs (CloudTrail, GCP, Okta, Azure Activity, Kubernetes audit, Windows Event Logs) and there was previously no portable way to match a member. The feature is documented in the new Array Matching guide and ships marked experimental because the surface syntax is still being finalized upstream.

Three constructs, all expressed with [...] selectors on the field path.

  • Implicit any-member. A plain field expression matches a scalar or any member of an array (connections: '1.2.3.1'), including through dotted paths into arrays of objects (connections.ip|cidr: '123.1.0.0/16'). This required fixing a first-match-wins bug in JsonEvent::get_field: a dotted path crossing an array now collects every element's leaf value, so any-member matching is correct rather than testing only the first element.
  • Object-scope blocks field[any]:, field[all]:, field[all_or_empty]:, and field[none]: open a nested detection evaluated against a single array member, for same-element correlation (one connection that is both protocol: TCP and in a suspicious CIDR). [any] requires at least one matching member; [all] requires a non-empty array where every member matches; [all_or_empty] is [all] but also matches an empty or missing array (the vacuously-true reading); [none] is the dual of [any] (no member matches) and matches an empty or missing array. The block body comes in two forms (the dual approach accepted in SEP #212): a basic conjunction map (the common case), and an extended nested detection with its own condition: plus named element-scoped sub-selections, for per-element and/or/not (for example "any connection in the CIDR that is not TCP"). The basic form is the implicit-AND degenerate case of the extended form. Inside a block body, a standalone . references the current scalar member (with modifiers, e.g. .|gte), so an array of scalars can carry multiple, named, or negated per-element predicates ("any 5xx response code that is not 504").
  • Positional indexing field[N] selects one element, for ordered arrays where each index carries meaning (args[0] is the process image, args[1..] are parameters). Indices may be negative (args[-1] is the last element, counting from the end). It is deterministic: a missing field, a non-array value, or an out-of-range index does not match. It composes with paths and quantifiers (connections[0].ip, rules[any].ip[0]).

Array selectors are kept strictly distinct from the existing all value-list modifier. Only an unescaped trailing [...] is a selector; a literal bracket in a field name is escaped as \[ / \] (mirroring the existing \* / \? wildcard escaping), so args\[0\] matches a field literally named args[0] rather than index 0.

New lint rule. flattened_array_correlation (warning) flags two or more sibling keys that share a quantified array prefix (e.g. connections[any].protocol and connections[any].ip); they open independent scopes and do not correlate on the same element, so the rule points authors at the object-scope block form. The lint catalogue now lists 66 built-in checks plus the 1 reserved enum value (empty_filter_rules).

Conversion. A new Backend::convert_array_match hook lowers the constructs where a backend can express them and errors with UnsupportedArrayMatching otherwise, never emitting a query with different semantics. The PostgreSQL/TimescaleDB backend lowers object-scope blocks to EXISTS / NOT EXISTS over jsonb_array_elements (guarded by jsonb_typeof(...) = 'array') and positional indices to ->n / ->>n (negative subscripts on PG 11+), in JSONB mode. Because [none] and [all_or_empty] must match an empty or missing array, they lower to a CASE that only unnests an actual array and treats a missing/null value as a match, so jsonb_array_elements is never applied to a scalar. The extended block body lowers to the same per-element primitive with a boolean inner predicate (the nested condition: becomes OR / parenthesized NOT over the element alias), so it costs no backend coverage. A backend that cannot lower a positional field[N] index rejects it (via the new Backend::supports_field_index capability) rather than emitting a literal field reference that would diverge from the evaluator; LynxDB, other text backends, and PostgreSQL flat-column mode report the construct as unsupported. Positional indexing is unexpressible in Elasticsearch query DSL because Lucene arrays are unordered sets, which is the strongest argument for evaluating the index in the engine.

AST and API. rsigma-parser gains ArrayQuantifier (Any, All, AllOrEmpty, None) and the Detection::ArrayMatch / Detection::And / Detection::Conditional variants, plus a fieldpath module of shared escape-aware helpers (bracket unescaping and unescaped-bracket detection) reused by the evaluator and converter; rsigma-eval gains the matching CompiledDetection variants. The rule index, bloom filter, and cross-rule Aho-Corasick prefilters no longer prune array-valued fields.

Tests. New parser, evaluator, and converter tests cover the flat-array, object-array fan-out, any/all/none/all_or_empty correlation and empty-array semantics, scalar-member, nested-quantifier, mixed-map, positional-index (including negative indices), extended-block (per-element negation, disjunction, and [all] with a nested condition), . scalar-element marker, and escaped-bracket literal-field cases, plus PostgreSQL golden SQL and unsupported-backend errors.

Strip the UTF-8 BOM from RFC 5424 syslog messages (#187)🔗

RFC 5424 section 6.4 mandates that a UTF-8 MSG begin with a byte order mark (U+FEFF, bytes EF BB BF) as an encoding marker, not as content. syslog_loose preserves it verbatim, and str::trim() does not remove it (U+FEFF is not Unicode White_Space), so the BOM previously leaked into the parsed event: it corrupted the _raw field and anchored matchers (startswith, exact equality), and it blocked embedded-JSON detection because serde_json errors on a leading BOM, silently degrading a BOM-prefixed JSON payload to a key/value event.

  • The syslog adapter now strips a single leading BOM from the message body by default, gated by a new SyslogConfig.strip_bom field (defaults to true).
  • Opt out with rsigma engine eval --syslog-strip-bom false / rsigma engine daemon --syslog-strip-bom false, or the input.syslog_strip_bom / eval.syslog_strip_bom config keys, to keep the message byte-for-byte.

rstix: STIX 2.1 + TAXII 2.1 library crate, Phase 1 core foundation (#185)🔗

Introduces rstix, a new workspace library crate for native STIX 2.1 and TAXII 2.1 support. This first phase lands the core foundation only; the object model, serialization dispatch, pattern engine, validation pipeline, and graph/marking/store/TAXII runtime behaviours are deferred to later phases.

  • Core primitives (rstix::core): a validated StixId in {type}--{uuid} form with 42 typed-ID wrappers and SDO/SCO/SRO/Meta kind discriminants; StixTimestamp and TaxiiTimestamp, where StixTimestamp preserves fractional-second precision for round-tripping but compares and hashes by instant so the same moment with different digit widths is treated as equal; Confidence plus six interchange scales (None/Low/Medium/High, Admiralty, 0-10, WEP, DNI, MISP); SpecVersion; LanguageTag; and the QueryableStixObject / QueryValue query traits.
  • Deterministic SCO IDs (rstix::id): generate_sco_id derives UUIDv5 identifiers from RFC 8785 (JCS) canonicalized contributing properties under the STIX namespace. Per-type property selection follows STIX 2.1, including single-hash selection by preference order, the spec-mandated UUIDv4 fallback for process and for objects with no contributing properties present, and a first-available-hash fallback for non-preferred algorithms. The generated IDs are pinned against python-stix2 golden vectors.
  • Vocabulary tables (rstix::vocab): open and closed STIX controlled vocabularies and the ordered OpinionValue enum, backed by compile-time phf sets.
  • Surface: #![forbid(unsafe_code)], a single default serde feature, and parse_bundle reserved as a NotImplemented entry point for the next phase. The workspace crate map, architecture page, and feature-flags reference are updated for the new crate.

Gated match-detail enrichment for detection results (#186)🔗

matched_fields entries can now explain why each field matched, gated behind a new opt-in verbosity level so the default wire shape is byte-for-byte unchanged.

  • New MatchDetailLevel { Off, Summary, Full } on rsigma-eval, configured via Engine::set_match_detail (and the CorrelationEngine passthrough). Off is the default and preserves the historical {field, value} shape exactly; all new keys are Option/skipped on serialization, so existing sinks, the daemon NDJSON wire format, and the golden tests are unaffected unless a caller opts in.
  • Summary adds selection (the originating named detection), matcher (a new MatcherKind enum: exact, contains, startswith, endswith, regex, one_of, cidr, numeric, exists, fieldref, null, bool, expand, timestamp, keyword), and case_sensitive. Full additionally records pattern, the value the matcher tested against (truncated for very long pattern sets). Negated matchers set negated: true.
  • Closed two long-standing reporting gaps (visible only at Summary/Full, so Off is untouched): keyword detections, which previously contributed nothing to matched_fields, are now reported under the sentinel field "keyword"; and null-on-absent matches, previously invisible because the field had no value, are now reported with value: null.
  • New CompiledMatcher::describe() (returning MatchDescriptor) produces the structural description used to populate these fields. It runs only when a rule matches and only above Off, so the non-matching hot path is unchanged.
  • CLI/runtime plumbing: rsigma engine eval --match-detail <off|summary|full>, rsigma engine daemon --match-detail <…> plus the daemon.engine.match_detail config key, and RuntimeEngine::set_match_detail (carried across hot reloads).

v0.14.0...v0.15.0

0.14.0 - 2026-06-05🔗

TL;DR RSigma v0.14.0 is the "layered config, structured output, and correctness/hardening" release: * Layered YAML configuration with explicit precedence (flag > env > project > user > system > default) plus a new rsigma config group (init, validate, show, schema, path, reload). * Structured output everywhere: a global --output-format <json|ndjson|table|csv|tsv> selector with a TTY-aware default, plus global --color, --quiet, and --no-stats. * Custom linter tag namespaces via a repeatable --tag-namespace flag and a tag_namespaces config key, so organisation-specific tags no longer force disabling unknown_tag_namespace wholesale, thanks to @fwosar. * Sigma correctness: multi-field value_count composite keys, compile-time rejection of multi-field numeric aggregations, empty value_median returns None, cross-crate detection-name selector consistency, and convert-side rejection of modifiers it cannot express. * Runtime hardening: a category-based HTTP egress policy (SSRF/cloud-metadata defense applied at DNS resolution), a 10 MiB enricher response cap, hot-reload that preserves engine tuning, and fail-closed dynamic-source resolution. * Evaluator and parser robustness: compile-time rejection of conflicting detection-modifier combinations, allocation-free JsonEvent dot-path traversal, and CLI diagnostics that stop silently swallowing invalid status / level / related: metadata. * Detached dynamic sources: pipeline-embedded sources: now warns louder on stderr and through the daemon hot-reload path. * Release pipeline, CI, Docker, and supply-chain hardening before publish, two batched Dependabot rollups, and a docs-accuracy sweep across the site.

Documentation accuracy: TLS, feature flags, metric and lint counts, CLI surface, endpoint inventory, benchmark freshness (#181)🔗

A docs-only sweep that closes the accuracy gaps that accumulated over the v0.13.x line. No source code changes; every fix points the documentation at the actual behaviour that ships in the binary.

  • Daemon TLS is no longer described as roadmap. docs/reference/http-api.md and docs/reference/architecture.md previously told operators that in-process TLS termination was planned and linked to issue #128. The daemon-tls Cargo feature, the --tls-cert / --tls-key / --tls-client-ca / --tls-min-version flag set, and the SIGHUP cert hot-reload all shipped in the v0.14.0 release window; both pages now point at the existing security.md#tls-termination-for-the-api-listener write-up instead.
  • Feature flag catalogue matches the manifest again. docs/reference/feature-flags.md opened by claiming a workspace of seven crates (it has been six since the binary / rsigma-cli split). The daemon-tls row listed rustls-pemfile as a pulled-in dependency; the actual manifest pulls rustls, tokio-rustls, rustls-pki-types, x509-parser, hyper, hyper-util, and tower-service. The "per-feature CI matrix" section described a per-feature opt-in matrix that does not exist in .github/workflows/ci.yml today (CI runs --all-features plus the three-OS test matrix). All three drifts are corrected, and the production-recommended cargo install recipe now includes daemon-tls.
  • Metric counts agree across the three pages that publish them. docs/reference/metrics.md headlined "30 metric names across four concerns" while its own section headings summed to 37 rows; the actual registry in crates/rsigma-cli/src/daemon/metrics.rs exposes 38 metric names under --all-features (33 always-present plus 3 OTLP and 2 TLS gated on the matching build features), grouped into seven concerns. Engine core is 17 metrics, not 16. docs/guide/streaming-detection.md and docs/guide/observability.md propagated the stale "27" number; both are now aligned, and observability gains the previously missing enrichment (6) and TLS (2) rows.
  • Lint rule counts are honest. docs/reference/lint-rules.md claimed 66 built-in checks; one of them (empty_filter_rules) is enum-only and not emitted in production. Page now reads "65 built-in checks plus 1 reserved enum value". The "Filter rules (7)" heading was actually a table of 8 rows including the reserved variant -- relabelled "Filter rules (8 IDs, 7 emitted)". The "Detection-modifier hygiene (5)" heading listed 7 rows that are not duplicates of the detection section above -- relabelled "Detection-modifier hygiene (7)" with the misleading "subset of the detection rules above" wording removed.
  • CLI global flags are fully documented. docs/cli/index.md listed only --log-format and asserted "every subcommand accepts one global flag", missing the other four globals (--output-format, --color, --quiet, --no-stats) that have shipped alongside it. The overview now describes all five with their defaults, accepted values, effect, and the layered flag > env > config > default precedence model. The command tree gains the previously omitted rule migrate-sources entry, and docs/cli/rule/lint.md drops the stale command-local --color flag (color is global now) and documents the four machine renderers (json, ndjson, csv, tsv) the lint command honours when --output-format is set explicitly.
  • Command-group overviews list every group. docs/getting-started/concepts.md claimed "the five command groups" but the table only listed four (engine, rule, backend, pipeline); add the missing config row with its six subcommands (init, validate, show, schema, path, reload). The rule row picks up migrate-sources. docs/reference/output.md drops rule validate from the table output consumers (the command always prints its bespoke per-file summary regardless of --output-format) and spells that out so operators are not surprised when the selector does nothing on that command.
  • POST /api/v1/sources/resolve/{source_id} is in the HTTP API inventory. The daemon registers both the body variant (/api/v1/sources/resolve with a JSON body that names one source) and the path-parameter variant (/api/v1/sources/resolve/{source_id} with no body). Only the body variant was documented; the path variant now appears in both the summary table and a short body section with the success response (200 {"status":"resolve_triggered","source_id":"..."}) and the two failure responses (404 when no dynamic sources are configured, 429 when a refresh for the same source is still in flight).
  • Benchmark figures are labelled as captured on v0.9.0. BENCHMARKS.md (and the docs-site mirror docs/benchmarks.md that includes it) carried Date: 2026-05-07 / Version: 0.9.0 headers; the workspace has since shipped through v0.13.0 and parts of the hot path have moved. Relabel as "Date captured" / "Captured on version" and add a one-paragraph freshness admonition that asks anyone refreshing the numbers to update the metadata block in the same commit.
  • Site-level loose ends. The llmstxt plugin block in mkdocs.yml now lists rule/migrate-sources, every cli/config/* page, reference/output.md, reference/configuration.md, and guide/enrichers.md -- five public pages that an LLM consuming the generated llms.txt had no way to surface before. docs/developers/testing.md had a stale CLI E2E table ("12 files / 167 tests") that missed seven files added since (cli_config.rs, cli_daemon_enrichment.rs, cli_daemon_fields_observer.rs, cli_daemon_tls.rs, cli_migrate_sources.rs, cli_output_format.rs, cli_sources_deprecation.rs); the page now lists 19 files with their per-file test counts and asks readers to verify the exact total against their tree rather than copy a stale number forward.

Eval and convert internals: modifier validation, dot-path perf, golden routing (#180)🔗

Three independent quality fixes for the evaluator and converter that all surface bugs the previous code silently swallowed or paid an avoidable allocation for.

Conflicting modifier combinations are now rejected at compile time. compile_detection_item previously turned the parsed modifier list into a flat boolean context and dispatched through compile_value in a fixed precedence order. Whichever flag the dispatch checked first won, so a rule declared as Field|cidr|contains silently produced a CIDR match with contains dropped, Field|re|contains produced a regex match with contains dropped, Field|gt|contains ran the numeric comparison and dropped contains, Field|exists|contains collapsed to an existence check that dropped both the substring matcher and the value, Field|wide|utf16 silently picked whichever UTF-16 dialect the dispatch implemented first, and Field|i with no |re silently became a no-op. The rules still compiled, still matched something, but the semantics were never what the author wrote. A new validate_modifiers pass runs before compile_value and rejects five categories of contradiction: more than one operator per item (the operator set spans contains / startswith / endswith / re / cidr / exists / fieldref / gt / gte / lt / lte and every timestamp part); more than one UTF-16 encoding from wide / utf16 / utf16be; base64 together with base64offset; any value transformation (base64 / base64offset / wide / utf16 / utf16be / windash / expand) on a field that also carries a non-string operator that does not consume the transformed value; and the regex flag modifiers (|i / |m / |s) without |re. Legal combinations stay legal: |re|i|m|s, |base64|wide, |contains|cased, |contains|all with multiple values, |contains|neq, |re|neq, and a single timestamp part all continue to compile. Errors flow through the existing EvalError::InvalidModifiers variant with a message that lists every offending modifier so the rule author can pick which one to drop. The full SigmaHQ corpus (rules/ plus rules-compliance/ plus rules-emerging-threats/ plus rules-placeholder/ plus rules-threat-hunting/, ~3.7k detection rules at the pinned CI SHA) compiles unchanged.

JsonEvent dot-path traversal no longer allocates per lookup. JsonEvent::get_field is called once per detection item per event for every nested-field rule (process.command_line, actor.id, …) and also drives keyword scans, group-key extraction for correlation, value-count and numeric aggregation field reads, FieldRef matchers, and timestamp extraction. The dot-notation branch previously did let parts: Vec<&str> = path.split('.').collect(); and walked the slice, allocating a small vector on every lookup whose only purpose was to be sliced once per recursion. The walker now consumes the leading segment with str::split_once('.') on each recursion and re-passes the unconsumed path on the array branch (matching the existing OR semantics for events.actors.name style lookups). The pathological trailing-dot case (a.b.) and consecutive-dot case (a..b) keep matching None rather than falsely returning the leaf or panicking; two regression tests cover both inputs.

Postgres and LynxDB goldens are now routed through convert_collection. Both runners previously parsed the SigmaCollection and called Backend::convert_rule in a loop, bypassing the orchestration layer that the rsigma backend convert CLI uses. The gap meant that pipeline-state plumbing, per-rule error collection, and the _rule_tables / _rule_schemas / _rule_queries correlation map injection were never exercised by the goldens. Both tests/golden_postgres.rs and tests/golden_lynxdb.rs now invoke convert_collection(&backend, &collection, &[], "default") and assert on the flattened query output, with a hard assertion on output.errors.is_empty() so a silent partial conversion now fails the test instead of producing an empty actual string. The 20 existing goldens (11 Postgres, 9 LynxDB) pass unchanged.

Parser and CLI diagnostics: invalid metadata, output controls, panic-free migrate (#179)🔗

Tightens five small but visible cracks in the parser and CLI surface that all silently swallowed problems an operator was almost certainly trying to catch.

Invalid status / level and malformed related: entries are now surfaced. parse_detection_rule, parse_correlation_rule, and parse_filter_rule previously coerced any unparseable status: or level: into a silent None (get_str(m, "status").and_then(|s| s.parse().ok())), and parse_related filter_mapped away any item that was not a mapping, was missing id/type, or carried an unknown type. A typo such as status: stabel or type: derved round-tripped to the in-memory rule with the field absent and no diagnostic. The parsers now thread a &mut Vec<String> for warnings, push index-qualified messages (related[2] invalid type 'derved' (expected one of: derived, obsolete, merged, renamed, similar)), and let parse_sigma_yaml extend SigmaCollection.errors with the result. Existing CLI surfaces (rule parse, rule validate, the "Loaded rules" path) already render collection.errors, so the new warnings flow through unchanged.

New SigmaCollection ergonomics. Three helpers cover the "treat any error as failure" path that downstream callers were re-implementing each time: SigmaCollection::has_errors(), SigmaCollection::error_count(), and SigmaCollection::into_result() (consumes the collection and returns Err(Vec<String>) when anything failed, Ok(self) on a clean parse). The stale doc on the errors field that referenced a non-existent collect_errors flag is replaced with the actual contract.

rule lint honours --quiet and --no-stats. Both global flags had no effect on the human renderer, so CI scrapers that piped only findings still got a "Loaded lint config: …" progress line on stderr and a "Checked N file(s): … passed, … failed" trailing summary on stdout. The summary block is now gated by OutputCtx::show_stats() and the config-load progress by show_progress(); findings still print under both flags. The structured tracing::info!("Lint summary", …) event continues to fire so log-based consumers still see the per-run totals.

Invalid global.output_format / global.color config values now warn instead of silently falling back. A typo like output_format: xml or color: rainbow in the YAML config used to bypass the OutputFormat::parse / ColorChoice::parse filter, return None, and revert the operator to the TTY-aware defaults with no signal. A new output::warn_invalid_global_output wrapper between config::discovered_global_output and OutputCtx::resolve validates both strings, emits a stderr warning that lists the accepted alternatives, and strips the bad value so the resolver still falls back cleanly. The command itself still succeeds because the warning is informational.

rule migrate-sources no longer panics on a pipeline read race. After writing the extracted sources.yml, the rewrite loop in cmd_migrate_sources re-read each pipeline file with std::fs::read_to_string(path).unwrap(). A file deleted between scan and rewrite (or a permission flip on a flaky filesystem) crashed the CLI. The read now matches the soft-error pattern the std::fs::write call below it already used: print a warning: line, skip the offending pipeline, and keep going. The extracted sources file is already on disk at that point, so a single unreadable pipeline does not invalidate the other rewrites.

Release pipeline, CI, Docker, and supply-chain hardening🔗

Tightens every link in the release chain before v0.14.0 ships so the act of publishing itself does not undermine the correctness work that already landed.

publish.yml no longer masks cargo publish failures with || echo "::warning::… already published or failed". A new pre-flight step dry-runs every crate in dependency order before any side-effecting publish; authentication, lockfile drift, and dependency-resolution issues now abort the workflow before any crate hits crates.io. Every actual publish passes --locked. The workflow_dispatch trigger keeps the dry-run rehearsal path; only release: published touches the real registry. The Swatinem/rust-cache step was removed to close a cache-poisoning vector against the signed artifacts.

release-binaries.yml pins the toolchain through dtolnay/rust-toolchain@... stable with targets: set inline (replacing the unpinned rustup update plus follow-up rustup target add). After downloading the per-target archives, the release job generates a SHA256SUMS manifest and uploads it as a release asset, covered by the same actions/attest-build-provenance subject path as the archives. Consumers who do not pull the SLSA attestation can still verify download integrity against the manifest.

Workspace. rust-toolchain.toml pins ambient cargo invocations to the MSRV of 1.88.0, so contributors who do not pass +stable build against the same Rust the MSRV CI job uses. A new [profile.release] block enables lto = "thin", codegen-units = 1, and strip = true. The pin surfaced an existing 1.88.0 clippy / rustdoc backlog (collapsible-else, uninlined-format-args, duplicated #[cfg(feature = "daemon-tls")], broken intra-doc links, unclosed <host> HTML tags); this release ships the cleanup so cargo clippy --workspace --all-targets --all-features -- -D warnings and cargo doc --workspace --no-deps -D warnings -D rustdoc::broken-intra-doc-links are gate-green.

CI. The Sigma corpus regression job now fetches SigmaHQ/sigma at a pinned commit (bumped by editing SIGMA_CORPUS_SHA in ci.yml) instead of master tip, so an upstream rule edit cannot turn the workspace red without a deliberate commit here. The MSRV check gains --all-targets so a test- or example-only dependency that requires a newer Rust cannot slip past the MSRV gate. The coverage job uploads lcov.info as an artifact for external trackers. A new doc job runs cargo doc --workspace --all-features --locked --no-deps with the strict rustdoc gate so a future broken intra-doc link fails CI rather than landing silently.

Docker. Both cargo build stages in the Dockerfile add --locked, and rust-toolchain.toml is part of the dependency-cache layer so the toolchain version is part of the layer's cache key. .dockerignore excludes /fuzz, /tests, /docs, /docs-drafts, /site, and /benches from the build context (root-anchored so per-crate tests/ subdirectories are unaffected). The Grype vulnerability scan runs as a 2-leg matrix (amd64 × arm64) so arch-specific CVEs cannot land on a release image unnoticed; SARIF uploads label findings by arch in the Security tab.

Supply chain. deny.toml denies wildcard dependency versions (wildcards = "deny"), surfaces unmaintained-crate advisories via unmaintained = "workspace", and grows a quarterly-review note plus "Last reviewed" date on the RUSTSEC-2021-0153 ignore. The audit workflow now triggers on deny.toml and its own workflow file in addition to manifest and lockfile changes, and pulls cargo-audit from taiki-e/install-action prebuilds instead of compiling it from source on every invocation. Dependabot picks up two new ecosystems: docker against / (so a new digest for the pinned rust:1-alpine base image surfaces as a PR) and npm against /editors/vscode (so the extension's TypeScript / @vscode/vsce / eslint deps follow the same weekly batching as the Cargo deps).

Runtime hardening: HTTP egress policy, body cap, hot-reload tuning, fail-closed dynamic sources (#167)🔗

Cluster of P0 hardening fixes for the daemon's HTTP surfaces and rule hot-reload. None of these were exploitable in a default deployment, but each silently produced behavior different from what the operator (or rule author) wrote, and all of them ship together before v0.14.0.

HTTP egress policy for sources and enrichers. Both the dynamic-source HTTP resolver and the HTTP enricher previously accepted any URL declared by a rule or pipeline, including the cloud-metadata IMDS endpoint at 169.254.169.254, IPv6 link-local (fe80::/10), and the AWS IPv6 metadata address fd00:ec2::254. The new rsigma_runtime::EgressPolicy describes a category-based deny list applied at DNS resolution time (EgressFilteredResolver implements reqwest::dns::Resolve), so DNS rebinding cannot defeat host-string checks. Three presets ship: default (block link-local + cloud metadata, allow loopback + private), strict (also block loopback + RFC1918 private), and permissive. Per-category builders (with_block_link_local, with_block_cloud_metadata, with_block_loopback, with_block_private) cover the in-between cases. The policy is selectable on rsigma engine daemon via --egress-policy <default|strict|permissive> and on the layered YAML config via daemon.engine.egress_policy. Default is default.

HTTP enricher response body cap. HttpEnricher::enrich used to consume the upstream body via reqwest::Response::bytes, which buffers the entire response into memory. A misbehaving enrichment endpoint streaming an unbounded body could OOM the daemon. The fetch path now checks Content-Length up-front and streams chunks with a 10 MiB ceiling (DEFAULT_ENRICHER_MAX_RESPONSE_BYTES, matching the existing source-side cap), configurable per enricher via with_max_response_bytes.

Engine tuning survives hot-reload. LogProcessor::reload_rules rebuilt the RuntimeEngine through RuntimeEngine::new, which defaults bloom_prefilter off, bloom_max_bytes to None, and (with daachorse-index) cross_rule_ac off. Daemons that enabled those flags at startup silently lost them on every reload. The reload path now snapshots those settings on the old engine via three new accessors (RuntimeEngine::bloom_prefilter, bloom_max_bytes, cross_rule_ac) and replays them on the new engine before load_rules runs.

Dynamic-source reload fails closed. RuntimeEngine::load_rules resolved dynamic sources inside block_in_place and, when resolution returned an error, logged a warning and continued with the captured pipelines as-is. ${source.*} placeholders stayed unexpanded, producing rules with semantics different from the operator's intent. On a hot-reload this silently replaced a healthy engine with a broken one. Both the "resolver failed" and "no tokio runtime available" branches now return an error from load_rules, so LogProcessor::reload_rules propagates it and skips the engine swap. The captured pipelines are restored before the error returns so a retry sees the same input state.

Shared HTTP client for dynamic sources. resolve_http_with_limit constructed a fresh reqwest::Client on every call. Under a refresh storm (a dynamic-source pipeline polling several feeds every 30 seconds) this rebuilt TLS state, DNS resolvers, and connection pools each iteration. A process-wide OnceLock<Arc<reqwest::Client>> exposed through sources::http::shared_http_source_client now backs every source fetch; per-call timeouts ride along via RequestBuilder::timeout(...). HTTP enrichers already shared an Arc<reqwest::Client> (build_default_http_client), and the policy resolver above is wired through both clients.

API additions. pub use from rsigma-runtime: EgressDenial, EgressFilteredResolver, EgressPolicy, default_egress_policy, set_default_egress_policy, enrichment::http::DEFAULT_ENRICHER_MAX_RESPONSE_BYTES, sources::http::shared_http_source_client. EngineStats now derives Debug / Clone / Copy. HttpEnricher::with_max_response_bytes is the only new method on an existing public type.

Tests. Cumulative: 12 new unit + integration tests across rsigma-runtime (egress policy categories, IPv4-mapped IPv6 recursion, builder overrides, filtered resolver against literal 169.254.169.254 and 8.8.8.8, body-cap rejection via Content-Length, body-cap rejection via chunked-stream overflow, reload tuning preservation, fail-closed dynamic source, shared client Arc identity) plus 2 new integration tests in rsigma-cli (engine.egress_policy config-to-flag flow and clap rejection of an invalid policy value). The 14 enrichment integration tests (wiremock on 127.0.0.1) and the 35 source integration tests continue to pass under the default policy.

Sigma correctness: multi-field correlations, empty median, unsupported convert modifiers (#166)🔗

Closes a cluster of silently-wrong evaluation and conversion behaviors so v0.14.0 ships none of them.

Multi-field value_count now uses a composite distinct-key. Previously the engine read fields.first() and ignored the rest, so field: [User, SrcIp] over events with the same user from different source IPs counted as one distinct value. The fix joins the rendered field values with the ASCII Unit Separator (\u{1f}) and counts distinct tuples; a missing field on any component drops the event (matching the prior single-field behavior). The single-field hot path keeps its old allocation profile.

Multi-field value_sum / value_avg / value_percentile / value_median are now rejected at compile time. The Sigma spec does not define how to combine several numeric fields under one of these aggregations. The previous behavior silently used only the first field and dropped data. The compiler now returns a structured CorrelationError listing the offending fields.

Empty value_median windows now return None. They used to return 0.0, which spuriously satisfied predicates like lte: 0 and eq: 0. The behavior now mirrors value_percentile, which already returned None for empty windows.

Detection-name selector matching is now consistent across crates. The evaluator's pattern_matches lacked the middle-* branch (sel*main) that the converter had, so the same selector pattern silently resolved to different detection sets in eval vs convert. Hoist a single detection_name_matches (plus SelectorPattern::matches_detection_name) into rsigma-parser and reuse it from both crates, with cross-crate tests covering exact, full wildcard, prefix wildcard, suffix wildcard, and middle wildcard cases.

The rsigma-convert default item dispatch rejects modifiers it cannot express. default_convert_detection_item previously fell through to Backend::convert_field_eq_str for any modifier it did not handle explicitly, so a rule using |neq, |base64, |base64offset, |wide, |utf16, |utf16be, |windash, |expand, regex flags without re (|m, |s), or timestamp parts (|minute/|hour/|day/|week/|month/|year) shipped SQL/SPL with different semantics from what the author wrote. The dispatch now returns ConvertError::UnsupportedModifier before the fall-through. Backends that handle one of these modifiers natively can override Backend::convert_detection_item and bypass the default. A defensive ok_or_else replaces the last unwrap() on the selector-dispatch path.

Dependency cleanup. base64 and ipnet were declared in crates/rsigma-convert/Cargo.toml but never referenced from anywhere under crates/rsigma-convert/src/. Dropped.

Docs. crates/rsigma-eval/README.md now explains that percentile selects which percentile to compute (not the threshold), that an empty window does not fire, and that the four numeric aggregations require a single field.

Custom tag namespaces for the linter (#161, #162)🔗

rsigma rule lint no longer forces teams to disable unknown_tag_namespace wholesale just to use organisation-specific tags. A repeatable --tag-namespace <ns> flag and a tag_namespaces list in .rsigma-lint.yml register extra namespaces that are recognised alongside the built-in spec set (attack, car, cve, d3fend, detection, stp, tlp). Namespace values are normalised to lowercase, and when unknown_tag_namespace does fire its message lists the full combined set of known namespaces.

On the library side, LintConfig gains a tag_namespaces field that layers through the same merge path as disabled_rules and exclude_patterns. Both list-valued fields, exclude_patterns and tag_namespaces, are now de-duplicated (first occurrence wins) when a config file and CLI flags are layered, so overlapping entries no longer accumulate. Docs cover the new flag and config key across the lint CLI reference, the linting guide, the lint-rules reference, and the linter developer guide; the CLI and root READMEs list the flag.

TTY-aware output + structured output formats (#157)🔗

Every rsigma subcommand can now emit its structured output in one of five formats, selected by a new global --output-format <json|ndjson|table|csv|tsv> flag. The default is TTY-aware: pretty JSON when stdout is a terminal, plain NDJSON when piped or redirected, so rsigma engine eval … | jq does the right thing without any extra flag and rsigma engine eval in a terminal is finally readable.

New global flags. Three more global knobs ride alongside --output-format and the existing --log-format:

  • --color <auto|always|never> honours NO_COLOR under auto (the default).
  • --quiet / -q suppresses every non-data line (progress, summary, fallback warnings); errors still go to stderr.
  • --no-stats suppresses only the trailing summary line; progress messages still appear.

All four resolve through the same layered precedence as the rest of the config: flag > RSIGMA_GLOBAL__* env > global.* in the YAML config > TTY-aware default.

Per-command rendering.

  • engine eval is the showcase. table renders a LEVEL | RULE | TYPE | DETAIL summary (numeric columns right-aligned). csv and tsv stream a header line plus one row per match. --pretty is preserved as a backwards-compatibility alias for "pretty JSON" and wins over the TTY default.
  • rule fields folds its --json flag into the new selector; --json is kept as a hidden deprecated alias for --output-format json. The legacy table view stays the default even when piped, so existing pipelines are unchanged. --output-format ndjson streams one field record per line.
  • rule lint keeps the coloured human view as the default. --output-format json emits a {summary, findings} envelope; ndjson streams one Finding per line; csv / tsv write a PATH,SEVERITY,RULE,LINE,MESSAGE table. The per-command --color flag is gone in favour of the global one; behaviour is identical.
  • rule parse, rule condition, rule stdin: routed through the shared JSON renderer; --pretty still defaults to on (the AST is small and human-friendly is the default).
  • backend convert: keeps its existing -f, --format for the backend query format and -o, --output for the output file unchanged. --output-format json wraps the queries in a {target, format, queries: [{rule_title, rule_id, query}, …]} envelope. The non-JSON tabular formats are not meaningful for free-form query text, so the command prints a stderr warning and falls back to raw text (the warning is itself suppressible with --quiet).

Output module. A new crates/rsigma-cli/src/output/ module owns the OutputFormat and ColorChoice enums, the OutputCtx resolver, the Tabular trait + width-aligning render_table (with auto-right-align for numeric columns), the streaming DelimitedWriter for CSV/TSV (hand-rolled RFC 4180-style escaping, no new dependency), and the Painter previously in commands/lint.rs (now reused by every command). The lint Painter is gone; the shared one resolves color from --color plus NO_COLOR plus TTY detection just like before.

Config schema. global.format is renamed to global.output_format (the old key was reserved for this work and was inert), and eval.format is dropped (it was inert too). The committed template, the JSON Schema emitted by rsigma config schema, and the schema drift-guard test all reflect the rename.

Tests. New unit tests in crates/rsigma-cli/src/output/mod.rs cover format / color parsing, TTY default resolution, --quiet / --no-stats semantics, CSV/TSV escaping edge cases, and the Tabular row shape. A new crates/rsigma-cli/tests/cli_output_format.rs integration suite (19 tests) exercises every format end to end on engine eval, rule lint, rule fields, and backend convert, plus the env-layer and config-file resolution and the flag-beats-env precedence.

Docs. New canonical docs/reference/output.md page (registered in docs/reference/.pages) covering formats, TTY behaviour, color, quiet/no-stats, precedence, and per-command behaviour. The eval CLI doc gains an output-format section and a table-view example; the env-vars doc lists the two new variables; root README and CLI README gain a Global flags section. The configuration reference example shows the new global.output_format / global.color keys.

Layered YAML configuration + rsigma config group (#152)🔗

engine daemon and engine eval are now driven by an optional layered YAML config file with explicit precedence CLI flag > env > project file > user file > system file > compiled default, applied per leaf. The same machinery is exposed through a new rsigma config command group for scaffolding, validation, introspection, and reload.

Discovery (lowest to highest precedence): compiled defaults, /etc/rsigma/config.yaml, $XDG_CONFIG_HOME/rsigma/config.yaml (defaulting to ~/.config/rsigma/config.yaml), the nearest .rsigmarc walked up from the current directory, ./rsigma.yaml, the environment layer, and finally CLI flags. --config <PATH> replaces the discovery chain entirely with one explicit file. The XDG path is computed by honouring XDG_CONFIG_HOME directly, not dirs::config_dir(), so macOS stays under ~/.config/rsigma to match the rsigma install layout.

Schema. A single typed RsigmaConfigPartial (Option-typed partial structs merged by a generic merge) covers three sections: global (currently log_format; color/format are reserved for the output-format work), daemon (mirrors every non-secret daemon flag, with nested api/api.tls/input/output/correlation/state/engine/nats sub-sections), and eval (mirrors the eval flag surface). Secret-bearing daemon settings (NATS creds/token/password/nkey, TLS key password) are deliberately absent from the schema; they remain env/flag-only.

Resolution. The resolver folds each layer's partial into a serde_json::Value with a generic deep-merge and tracks the winning layer per leaf (default, file, env, flag). CLI flag wins are detected via clap ArgMatches::value_source; the env layer reads a uniform RSIGMA_<SECTION>__<KEY> scheme (the __ separator deliberately leaves the existing single-underscore clap-bound names like NATS_CREDS and RSIGMA_CONSUMER_GROUP untouched). Values are parsed as YAML scalars so ints/bools/lists coerce naturally. A defaults module of named constants is the single source of every default; clap's default_value attributes are referenced from those constants and a drift-guard test pins the two together.

rsigma config subcommand group. Six subcommands, all agent-friendly (data to stdout, diagnostics to stderr):

  • config init [-o PATH] [--force] writes a commented template (default ./rsigma.yaml) with a # yaml-language-server: $schema= header. Refuses to overwrite without --force.
  • config validate [-c PATH] [--format text|json] [--strict] deserializes every layer, warns on unknown keys via serde_ignored, warns on sections set but inert in this build (daemon.api.tls without daemon-tls, daemon.nats without daemon-nats, daemon.engine.cross_rule_ac without daachorse-index), and prints a structured envelope ({ ok, sources, unknown_keys, inactive_sections }) in JSON mode. --strict upgrades unknown keys to exit 3.
  • config show [-c PATH] [--for global|daemon|eval] [--format text|json|yaml] prints the effective config (defaults < file < env) with the source of each leaf.
  • config schema emits a JSON Schema (draft 2020-12) derived from the same partial structs the loader uses, via schemars::JsonSchema. The schema is what powers editor autocomplete (yaml-language-server) and what agents/CI can validate against.
  • config path [-c PATH] lists the config files that would be loaded.
  • config reload [--addr ADDR] [-c PATH] triggers a daemon hot-reload via POST /api/v1/reload, mapping 0.0.0.0/[::] bind addresses to loopback so the client can actually connect. Cross-platform (works on Windows, where SIGHUP does not exist); kill -HUP <pid> still works on unix.

Command wiring. DaemonArgs and EvalArgs both gain --config <PATH> and --dry-run. --rules is now optional on both: it can be supplied via daemon.rules / eval.rules instead, with a clear error if neither layer provides it. main() now goes through Cli::command().get_matches() + from_arg_matches so the daemon and eval dispatch paths (including the deprecated flat daemon and eval aliases) can hand the sub-ArgMatches to the resolver. global.log_format from a discovered config file (or RSIGMA_GLOBAL__LOG_FORMAT) drives the CLI log subscriber when --log-format is not passed, so the global section is no longer inert.

Dependencies. Adds the tiny serde_ignored 0.1 (unknown-key detection) and promotes schemars 1.x (already present transitively via jsonschema) to a direct dependency. No new top-level versions in Cargo.lock beyond serde_ignored. --config reload reuses the existing ureq dependency.

Tests. Unit tests cover layered file discovery, serde_ignored unknown-key collection, per-field precedence on both daemon and eval (CLI > env > file > default), JSON deep-merge with Null no-op, the RSIGMA_*__* env scheme, and the daemon-defaults drift guard. A new crates/rsigma-cli/tests/cli_config.rs integration suite (10 tests) exercises the real binary end to end: config init round-trips (the committed template validates clean and carries zero unknown keys), --force guard, unknown-key warnings + --strict exit, missing-file error, JSON schema emission, config show JSON source annotations, config path, and the config-to-command flow (engine eval reading rules from config, an explicit --rules overriding the config, and engine daemon --dry-run printing config values).

Docs. New docs/cli/config/{init,validate,show,schema,path,reload}.md pages with a .pages nav entry, a canonical docs/reference/configuration.md page (precedence, discovery, schema, env scheme, secrets policy, --dry-run semantics, version: 1 migration field) registered in docs/reference/.pages, --config and --dry-run rows added to docs/cli/engine/daemon.md and docs/cli/engine/eval.md, the top-level docs/cli/index.md updated to include the new config group in the quick-nav and command tree, and docs/reference/environment-variables.md rewritten to document the uniform RSIGMA_<SECTION>__<KEY> scheme alongside the legacy single-underscore names. Root README gains a Configuration section and the CLI README a config block under Subcommands.

Pipeline-embedded sources: deprecation gets louder (#140, closes #136)🔗

Phase 3 of the detached-dynamic-sources cycle. Pipeline files that declare an inline sources: block now print a warning: line on stderr in addition to the existing tracing::warn! event:

warning: pipeline '<name>' (<path>) declares an inline 'sources:' block, which is deprecated and will be removed in v1.0. Migrate with `rsigma rule migrate-sources -p <path> -o sources.yml` and load via `--source sources.yml` on `rsigma engine daemon`.

The structured warning is unchanged (now enriched with a path field), so log aggregators that already parse the message keep working. The emission moves out of commands/daemon.rs into a new public rsigma_runtime::warn_pipeline_inline_sources helper that two paths share:

  • CLI startup. The CLI's load_pipelines (the entry point for engine eval, engine daemon, rule validate, rule fields, backend convert) and pipeline resolve both call the helper directly for every pipeline file loaded at startup.
  • Daemon hot-reload. RuntimeEngine::load_rules -> reload_pipelines in rsigma-runtime now calls the helper too, so a SIGHUP, file-watcher event, or POST /api/v1/reload that re-reads a deprecated pipeline surfaces the warning even though the daemon's reload path does not go back through the CLI's load_pipelines. Library consumers that drive RuntimeEngine themselves inherit the same behaviour.

Canonical-path deduplication via a process-wide OnceLock<Mutex<HashSet<PathBuf>>> inside the helper keeps the daemon from re-spamming the same pipeline path on every reload tick once the warning has already fired for it.

Doc and README sweep. Every example for dynamic sources now declares them in a standalone YAML file loaded via --source. The pipeline-embedded form is documented only as a short "Deprecated" callout that points operators at rsigma rule migrate-sources and the v1.0 removal issue (#137). The reference page (docs/reference/dynamic-sources.md), the user guide (docs/guide/processing-pipelines.md and docs/guide/enrichers.md), the daemon CLI page (docs/cli/engine/daemon.md), the top-level README, the CLI README, and the runtime README all switch to the external-file form. The CLI README's recipe-catalog refresh values also switch from the unsupported { interval: ... } mapping form to the literal-duration syntax (1h, 24h) that the parser actually accepts.

Deprecation timeline. v0.13.0 (#135) introduced the tracing::warn!. This release adds the louder stderr warning, plumbs the warning through the daemon hot-reload path, and hides the deprecated form from docs. v1.0 (#137) turns it into a hard parse error and removes the Pipeline.sources field.

Tests. A new cli_sources_deprecation.rs integration suite pins the stderr emission across rule validate, engine eval, and pipeline resolve, plus the dedup invariant when the same pipeline is passed twice via -p, the negative case (pipelines without inline sources do not warn), and the migration-command suggestion (the warning embeds the actual pipeline path so the suggested rsigma rule migrate-sources invocation is copy-pasteable). Three new unit tests in crates/rsigma-runtime/src/engine.rs exercise the runtime path directly: a RuntimeEngine::load_rules call records the canonical pipeline path in the dedup set, a clean pipeline does not, and a hot-reload (second load_rules call) leaves the dedup set unchanged. Two more in crates/rsigma-runtime/src/pipeline_deprecation.rs cover the dedup primitive in isolation.

Dependency bumps (#156)🔗

Rolls up four open Dependabot PRs into a single merge. Rust: serde_json 1.0.149 to 1.0.150 and tower-http 0.6.10 to 0.6.11 in the workspace Cargo.lock (#154), with the same serde_json bump applied to fuzz/Cargo.lock alongside a resync of that stale lockfile to the current workspace state (the jaq 3.0 migration to jaq-core / jaq-json / jaq-std and the internal crate versions catching up from 0.11.0 to 0.13.0) (#153). CI: taiki-e/install-action 2.78.0 to 2.79.3, docker/build-push-action 7.1.0 to 7.2.0, github/codeql-action 4.35.4 to 4.35.5, and zizmorcore/zizmor-action 0.5.5 to 0.5.6, all repinned by commit SHA (#155). VS Code extension: the tmp dev dependency bumps 0.2.5 to 0.2.7, picking up the upstream security fix that rejects non-string and relative prefix / postfix / template values.

Dependency bumps (#178)🔗

Rolls up eight open Dependabot PRs into a single merge. Docker: the rust:1-alpine base image digest moves from 606fd31 to 66f48b1 (#169). CI (all repinned by commit SHA, batched via the actions-updates group, #177): taiki-e/install-action 2.79.3 to 2.79.12, EmbarkStudios/cargo-deny-action 2.0.18 to 2.0.20, docker/setup-buildx-action 4.0.0 to 4.1.0, docker/login-action 4.1.0 to 4.2.0, github/codeql-action 4.35.5 to 4.36.0, and docker/metadata-action 6.0.0 to 6.1.0. Rust (workspace Cargo.lock): log 0.4.29 to 0.4.30 in the patch-updates group (#173), async-nats 0.48.0 to 0.49.0 (#174), and hyper 1.9.0 to 1.10.0 (#175). VS Code extension: @types/vscode ^1.116.0 to ^1.120.0, @vscode/vsce ^3.9.0 to ^3.9.1, and esbuild ^0.27.7 to ^0.28.0 in the npm-updates group (#170); typescript ^5.9.3 to ^6.0.3 (#171); @types/node ^20.19.39 to ^25.9.1 (#172). The three VS Code PRs all touched editors/vscode/package.json and package-lock.json; resolved by keeping the newest version from each PR and regenerating the lockfile with npm install --package-lock-only --ignore-scripts. The rusqlite 0.39.0 to 0.40.0 bump (#176) is deliberately deferred: it pulls in libsqlite3-sys 0.38.0, whose build.rs uses the cfg_select! macro that is not stable on the workspace MSRV of 1.88.0. It will be re-batched once MSRV is raised.

0.13.0 - 2026-05-26🔗

TL;DR RSigma v0.13.0 is the "post-evaluation enrichment, server-side TLS, and field observability" release: * Post-evaluation enrichment between engine.evaluate() and the sinks: four primitives (template, lookup, http, command), strict detection-vs-correlation kind separation, scope filters, on_error policies, six new Prometheus metrics, and a public register_builtin(name, factory) registry. * Server-side TLS on the daemon API listener (Axum REST + Prometheus + OTLP/HTTP + OTLP/gRPC sharing one socket via ALPN), gated by the new daemon-tls Cargo feature, with optional mutual TLS and cross-platform cert hot-reload via POST /api/v1/reload. * Field observability: opt-in --observe-fields on engine daemon and engine eval exposes the gap and broken-coverage signals via four /api/v1/fields/* endpoints and three Prometheus surfaces, sharing a RuleFieldSet + FieldCoverage join primitive across CLI and daemon. * Detached dynamic sources: declare sources in standalone YAML loaded via --source <file_or_dir>, with a unified DaemonSourceRegistry and a new rsigma rule migrate-sources helper. Pipeline-embedded sources: is visible-deprecated this release. * Library API: MatchResult and CorrelationResult collapse into a single EvaluationResult (RuleHeader + ResultBody), wire shape preserved. Deprecated CLI aliases are now hidden from rsigma --help. The reserved-but-empty attack subcommand group is removed. * Dependency bumps: jsonschema 0.46.5, jaq-core / jaq-std 1.x to 3.0 with jaq-json 2.0 (Radically Open Security audit fixes), assert_cmd 2.2.2, plus CI action bumps and two VS Code Dependabot security fixes (@azure/msal-node ^5.2.2, brace-expansion ^5.0.6).

Unknown-field discovery API (#149)🔗

The engine daemon learns to surface two halves of detection coverage live from inside the process: which event fields are not referenced by any loaded rule (gap signal) and which rule fields have never appeared in an event (broken-coverage signal). RSigma owns both rule parsing and event ingestion end-to-end, so this view does not need an external pipeline.

Two new flags on rsigma engine daemon (off by default; zero overhead when not set):

Flag Default Purpose
--observe-fields off Enable the field observer. When enabled, every event evaluated by the engine task has its dotted field paths recorded.
--observe-fields-max-keys <N> 10000 Hard ceiling on distinct field names. Existing keys keep counting once the cap is hit; new keys are dropped and counted as overflow.

Four new HTTP endpoints.

Method Path Description
GET /api/v1/fields Snapshot bundling summary + unknown + missing for a one-shot dashboard read.
GET /api/v1/fields/unknown Event fields not referenced by any rule. Sorted by descending count.
GET /api/v1/fields/missing Rule fields never seen in events. Each entry includes up to 10 rule titles with a truncated flag for fields that span more rules.
DELETE /api/v1/fields/observer Clear the observer's counters and return {previous_keys, previous_events}.

Each list endpoint accepts ?limit=N&offset=M (default limit=100, cap 1000) and returns total + next_offset for deterministic pagination. All four return 503 Service Unavailable with {"error":"field observation disabled","hint":"..."} when --observe-fields is not set.

Three new Prometheus surfaces.

Metric Type Description
rsigma_fields_observed_total counter Total events scanned by the opt-in field observer.
rsigma_fields_observer_unique_keys gauge Distinct field names currently tracked.
rsigma_fields_observer_overflow_dropped_total counter New-key insert attempts dropped because the observer was at capacity.

The gauges refresh on every /metrics scrape and after every successful /api/v1/fields/* call, so a Prometheus alert on rsigma_fields_observer_overflow_dropped_total fires the moment an operator's --observe-fields-max-keys choice is too low for the deployment.

Shared extraction with rsigma rule fields. The rule-field side of the join lives in a new rsigma_eval::fields module (RuleFieldSet) that both the CLI subcommand and the daemon import. The daemon caches the post-pipeline set on RuntimeEngine via ArcSwap and refreshes it on every successful load_rules(), so the HTTP handlers run lock-free against a stable view even during hot reloads.

Shared join primitive. FieldObservation::coverage(&RuleFieldSet) -> FieldCoverage lives in rsigma-eval and partitions an observation snapshot into the unknown / intersection / missing buckets in one pass. Both the daemon's HTTP handlers and the eval report consume this, so the partition semantics cannot drift across runtimes.

Implementation cost. Default-off; the engine task takes a single ArcSwap load per batch when no observer is attached and skips field iteration entirely. With --observe-fields set, the only added work is one Event::field_keys() walk per parsed event (one String allocation per leaf path, depth-capped at 64; flat formats like KvEvent return Cow::Borrowed) plus a short std::sync::Mutex lock to update counters. Memory is bounded by --observe-fields-max-keys (10k default ≈ a few hundred KB; keys stored as Arc<str> so snapshots refcount-bump rather than copy).

Offline coverage report. rsigma engine eval mirrors the daemon's field-observability surface with three new flags: --observe-fields enables observation; --observe-fields-max-keys <N> (default 10000, validated as NonZeroUsize so 0 is rejected at parse time); --observe-fields-report <PATH> writes the JSON report to a file (defaults to stderr if omitted so detections on stdout stay machine-consumable; clap-requires --observe-fields so the typo case fails fast). The report has the same shape as GET /api/v1/fields, so the same jq queries work against either runtime. To make this possible without coupling engine eval to the daemon Cargo feature, FieldObserver lives in rsigma-eval (which every consumer already links) and uses std::sync::Mutex to keep rsigma-eval dependency-light. rsigma-runtime keeps a pub use rsigma_eval::{FieldObserver, FieldObservation, FieldObservationEntry, FieldCoverage} re-export so existing imports continue to compile unchanged.

Docs. Endpoint reference under "Field observability" in docs/reference/http-api.md; flag rows in docs/cli/engine/daemon.md and docs/cli/engine/eval.md; metric rows in docs/reference/metrics.md; combined daemon/eval workflow in docs/guide/observability.md.

Server-side TLS for the daemon API listener (#128)🔗

The engine daemon API listener now terminates TLS in-process for every protocol that already shares --api-addr: the Axum HTTP REST API (/healthz, /readyz, /metrics, /api/v1/*), OTLP/HTTP on POST /v1/logs, and OTLP/gRPC via LogsService/Export. Operators can drop the sidecar reverse proxy they previously needed for confidentiality, integrity, and agent-to-daemon pinning.

New Cargo feature. daemon-tls on rsigma-cli gates the TLS surface and pulls in rustls (with the aws-lc-rs provider, matching the NATS client TLS path and inheriting upstream FIPS-mode work), tokio-rustls, rustls-pemfile, rustls-pki-types, x509-parser, and hyper/hyper-util. The default build is unchanged.

Six new flags on rsigma engine daemon.

Flag Env Default Purpose
--tls-cert <PATH> -- -- PEM-encoded leaf certificate (chain). Requires --tls-key.
--tls-key <PATH> -- -- PEM-encoded private key (PKCS#8, PKCS#1, or SEC1). Requires --tls-cert.
--tls-key-password <PASS> RSIGMA_TLS_KEY_PASSWORD -- Password for an encrypted --tls-key. Currently rejected with a clear hint pointing at openssl rsa for offline decryption; reserved for a future release.
--tls-client-ca <PATH> -- -- PEM bundle of trusted CAs. Enables mutual TLS: clients without a CA-signed cert are rejected during the handshake.
--tls-min-version <1.2\|1.3> -- 1.3 Minimum negotiated TLS protocol version.
--allow-plaintext -- off Opt-in for plaintext on a non-loopback --api-addr.

Plaintext refusal policy. When daemon-tls is built in, the daemon refuses to start on any non-loopback address unless either --tls-cert/--tls-key or --allow-plaintext is supplied. Loopback (127.0.0.0/8, ::1) always allows plaintext to keep local development friction-free.

Unified serving path. The implementation collapses the previous split between axum::serve (for plaintext non-OTLP) and tonic::transport::Server::serve_with_incoming_shutdown (for OTLP) into a single axum::Router built via tonic::service::Routes::into_axum_router. For TLS, a small custom axum::serve::Listener wraps the TcpListener and performs the tokio-rustls handshake on every accepted connection. ALPN advertises both h2 and http/1.1, so the same socket continues to serve REST + Prometheus + OTLP/HTTP + gRPC after TLS termination.

Cross-platform cert hot-reload. Cert rotation funnels through the daemon's central debounced reload task, which is triggered by POST /api/v1/reload (works on every platform, including Windows), SIGHUP (Unix), or a YAML change picked up by the file watcher. All three paths re-read the certificate and key from disk and atomically swap the active rustls::ServerConfig via Arc<ArcSwap<…>>. Inflight TLS connections are not dropped; failed reloads keep the previous certificate active, bump rsigma_reloads_failed_total, and log an error so a typo in the cert path cannot black-hole the listener. Encrypted-key support and ACME/Let's Encrypt automation are intentionally out of scope; operators rotate cert files (cert-manager, certbot, Vault PKI, ...) and trigger a reload.

Two new Prometheus metrics.

Metric Type Description
rsigma_tls_certificate_expiry_seconds gauge Seconds until the active TLS server certificate's not_after. Signed: negative once expired. Updated at startup and after every successful reload.
rsigma_tls_active_connections gauge Currently active TLS-terminated connections on the API listener. Decrements on connection close (including handshake failure).

A single WARN is logged at startup (and after every successful reload) when the active cert expires within 30 days, so operators can plug the line into existing log-based alerting alongside the longer-horizon Prometheus alert on rsigma_tls_certificate_expiry_seconds.

Docs. Full reference under "TLS termination for the API listener" in docs/reference/security.md; flag table in docs/cli/engine/daemon.md; agent recipes (Grafana Alloy, Vector, Fluent Bit, OpenTelemetry Collector) with tls/mTLS blocks in docs/guide/otlp-integration.md; quick-start note in docs/getting-started/quick-start.md; new row in docs/reference/feature-flags.md; two new alerts in docs/reference/metrics.md.

Deprecated CLI aliases hidden from --help (#125)🔗

The 12 flat top-level CLI aliases (eval, daemon, parse, validate, lint, fields, condition, stdin, convert, list-targets, list-formats, resolve) introduced as visible-deprecated forwarders in v0.12.0 (PR #124) are now hidden from rsigma --help via #[command(hide = true)]. The dispatch arms and the deprecation_warn helper are otherwise unchanged, so:

  • Every alias still runs successfully and still prints the migration warning on stderr.
  • rsigma <alias> --help is still routable and renders the same flag list as the new grouped form, so scripts that introspect a subcommand keep working.
  • rsigma --help now lists only the four noun-led groups (engine, rule, backend, pipeline) plus help.

The warning text was updated from "This alias will be hidden in the next release and removed in v1.0." to "This alias is hidden from --help and will be removed in v1.0." to reflect the new lifecycle stage. Removal at v1.0 is tracked in #126.

Detached dynamic sources (#135)🔗

Dynamic source declarations are decoupled from pipeline YAML files. Sources are now a first-class daemon-level concept declared in standalone YAML files and loaded via the new --source <file_or_dir> flag (repeatable). Both pipelines and enrichers reference sources by source_id as before; the daemon resolves them through a unified DaemonSourceRegistry that enforces collision-error semantics (same ID in two sites is a startup error with both paths in the message).

Pipeline-embedded sources: is deprecated. Existing pipeline files that declare sources: continue to work but emit a tracing::warn! at parse time recommending --source and rsigma rule migrate-sources. The deprecation runs over three releases: visible-deprecated this release, hidden from docs next release (#136), removed at v1.0 (#137).

New subcommand. rsigma rule migrate-sources -p <pipeline-dir> -o <out> extracts every pipeline-embedded sources: block into a standalone file, deduplicating by source ID with collision detection, and rewrites the pipeline files with the sources: block removed. Supports --strategy single (default, one consolidated file) and --strategy per-pipeline.

CLI flag additions. --source-file on rsigma pipeline resolve and --source on rsigma rule validate --resolve-sources so offline tooling can validate pipelines that reference external sources.

API change. GET /api/v1/sources now returns an origin field on each entry (external:<path> or pipeline:<name>) instead of the previous pipeline field.

Post-evaluation enrichment (#134)🔗

The daemon now runs a configurable enrichment pipeline between engine.evaluate() and the sinks. Each detection or correlation gets context (asset owner, IP reputation, identity, GeoIP, KEV flag, runbook URL, ...) injected into its RuleHeader::enrichments map before serialization, so every downstream consumer sees the same structured data without re-fetching it.

New flag. rsigma engine daemon --enrichers <PATH> points at a YAML file with max_concurrent_enrichments: <N> (default 16) plus a list of enricher entries. The file is hot-reloaded on SIGHUP, file-watcher events, and POST /api/v1/reload; a reload that fails validation logs the error and keeps the previous pipeline active, so a typo never silently degrades production to "no enrichment".

Four primitives. Every entry declares a type: from a fixed set, modeled on what Splunk (lookup + rest), Cribl Stream (Lookup + HTTP + Code + Eval), and Vector (enrichment_tables + remap) all converged on:

type Surface
template Pure string interpolation. No I/O. Used for runbook URLs and synthetic identifiers.
lookup Reads a dynamic source (as declared today via pipeline sources:) from the existing Arc<SourceCache> by source_id, with an optional jq / JSONPath / CEL extract to slice the cached value and an optional default for cache miss or no extract match. Zero-network-cost.
http Per-result reqwest request with template-expanded URL, headers, and optional body. Optional response cache keyed on (method, url, body_hash) with configurable TTL is mandatory in practice for any rate-limited API.
command Per-result tokio::process::Command invocation with template-expanded argv and environment. Stdout capped at 10 MiB; output parsed as JSON (default) or raw string.

The IRQL-style catalog (enrich_ip_employee, enrich_ip_geoip, enrich_hash_virustotal, enrich_cve_kev, enrich_url_runbook, enrich_ip_passive_dns) ships as field-parametric YAML recipes in docs/guide/enrichers.md, not Rust code. External crates that need a Rust-coded named enricher (bundled data, complex parser, stable contract, non-obvious algorithm) register one via the public register_builtin(name, factory) API.

Strict kind separation. Every enricher declares kind: detection | correlation. The kind drives two checks. At config load time, a kind: detection enricher may only reference ${detection.*} template variables and a kind: correlation enricher may only reference ${correlation.*}; cross-namespace references are rejected with a clear error pointing at the offending field. At runtime, the pipeline skips enrichers whose declared kind does not match the current EvaluationResult body variant before invoking enrich(), so a detection-kind enricher pays no cost on correlation results and vice versa. Available variables are documented in the Kind and template namespaces section of docs/guide/enrichers.md.

scope filtering and on_error policies. Within its declared kind, an enricher can be limited via scope.rules (rule ID or title glob), scope.tags (tag-set intersection with prefix.* wildcards), and scope.levels (severity membership). Axes are AND-ed; an empty axis is not a filter. On failure, on_error selects between skip (drop the enrichment, keep the result), null (inject null), and drop (drop the entire result). The default is skip, so an enrichment outage never silently swallows detections.

Six new Prometheus metrics. All six are pre-registered at startup, so every label triple renders with # HELP and # TYPE lines and zero counts on the first scrape, before any event has fired:

Metric Labels
rsigma_enrichment_total enricher_id, kind, status (success/skip/error/timeout/drop)
rsigma_enrichment_duration_seconds enricher_id, kind
rsigma_enrichment_queue_depth --
rsigma_enrichment_http_cache_hits_total enricher_id
rsigma_enrichment_http_cache_misses_total enricher_id
rsigma_enrichment_http_cache_expirations_total enricher_id

Filtered (kind- or scope-mismatched) enricher calls do not increment any counter, so cardinality stays bounded by the number of configured enrichers.

Library API. rsigma-runtime exports the Enricher async trait, EnrichmentPipeline, EnricherKind, OnError, Scope, the four primitive types (TemplateEnricher, LookupEnricher, HttpEnricher, CommandEnricher), HttpEnricherClient, HttpResponseCache, OutputFormat, the MetricsHook trait, and the register_builtin(name, factory) registry. Reserved names (template, lookup, http, command) are rejected at registration time; duplicate registrations of the same name are rejected to keep the registry append-only.

Documentation. New docs/guide/enrichers.md (config schema, the four primitives, recipes catalog, promotion criteria, output shape, metrics) and docs/developers/adding-enrichers.md (testing pattern, metrics wiring, naming conventions). docs/cli/engine/daemon.md, docs/library/runtime.md, and docs/reference/metrics.md updated. The crates/rsigma-cli/README.md gains a full enrichment surface section that mirrors the docs-site guide.

New dependencies. humantime and arc-swap in rsigma-cli (humantime for 5s / 1h duration parsing in the YAML; arc-swap for the hot-reload swap), globset and jaq-core / jaq-std / jaq-json in rsigma-runtime (globset for scope.rules / scope.tags patterns; the jaq additions wire the enrichment extract flow through jaq 3.0). wiremock added as a dev-dependency in both crates for HTTP enricher integration tests.

Unified evaluation result type (#132)🔗

MatchResult and CorrelationResult are collapsed into a single EvaluationResult via composition. The five fields shared between detection and correlation today (rule_title, rule_id, level, tags, custom_attributes) move into a new RuleHeader struct along with a new optional enrichments map. Kind-specific fields live in DetectionBody and CorrelationBody, behind a #[serde(untagged)] ResultBody enum.

Wire shape preservation. Both the header and the body flatten into the parent JSON object via #[serde(flatten)], so each NDJSON line remains a single flat object: same field set, same values, same skip_serializing_if behavior. Downstream consumers continue to distinguish detection from correlation by presence of correlation_type (correlation-only). The one cosmetic change is key order on rules with a non-empty custom_attributes map: custom_attributes is now emitted between the rule header fields and the kind-specific body fields rather than after them. JSON objects are unordered per spec, so this is invisible to compliant consumers; the golden snapshot tests at crates/rsigma-eval/tests/wire_shape_golden.rs pin the new ordering for both kinds.

Library API is breaking but pre-1.0. The old MatchResult, CorrelationResult, and the struct shape of ProcessResult { detections, correlations } are replaced by:

  • EvaluationResult (the single result type)
  • RuleHeader, DetectionBody, CorrelationBody, ResultBody (the composable parts)
  • ProcessResult (now a type alias for Vec<EvaluationResult>; detections come first, correlations after, in evaluation order)
  • ProcessResultExt extension trait on [EvaluationResult] exposing detections() / correlations() iterators and detection_count() / correlation_count()

Migration on the consumer side:

Before After
m.rule_title, m.tags, etc. m.header.rule_title, m.header.tags, ...
m.matched_fields, m.event m.as_detection().unwrap().matched_fields, m.as_detection().unwrap().event
m.correlation_type, m.group_key, ... m.as_correlation().unwrap().correlation_type, ...
result.detections.len() result.detection_count()
result.correlations.iter() result.correlations()
result.detections[0] result.detections().next().unwrap()

Internally, the three duplicated for m in &result.detections / for m in &result.correlations loops in the file, stdout, and NATS sinks collapse to one for m in result loop.

A new Criterion bench (crates/rsigma-eval/benches/result_serialize.rs) pins serialize throughput of the new design against a byte-for-byte copy of the old types across four representative inputs; the derived #[serde(flatten)] path is within ±4% of the baseline on every sample.

Drop reserved attack subcommand🔗

The empty attack command group that v0.12.0 reserved as a forward declaration for MITRE ATT&CK tooling is removed. The corresponding Commands::Attack clap variant, the AttackCommands enum, the dispatcher branch, the help-text test assertion, and the "reserved; populated by the upcoming MITRE ATT&CK contributor PR" README line are gone. The CLI now exposes four groups instead of five (engine, rule, backend, pipeline); the attack namespace remains available for a future contributor PR to populate but is no longer reserved ahead of time.

Dependency and security bumps (#145)🔗

Rolls up five open Dependabot PRs and closes two Dependabot security alerts. Rust: jsonschema 0.46.5, assert_cmd 2.2.2 (#141), and jaq-core / jaq-std 1.x to 3.0 with the new jaq-json 2.0 (#142, #143) -- the jaq 3.0 release ships the Radically Open Security audit fixes and a new Loader + Compiler + Ctx API that both apply_jq sites in rsigma-runtime and rsigma-cli are ported to; valid jq expressions in extract: and --jq are unaffected. CI: cargo-deny-action 2.0.18, taiki-e/install-action 2.78.0, zizmor-action 0.5.5 (#144). VS Code extension: top-level npm overrides bump @azure/msal-node to ^5.2.2 (drops the vulnerable uuid 8.x, closes GHSA-w5hq-g745-h8pq, #138) and brace-expansion to ^5.0.6 (closes CVE-2026-45149).

Other changes🔗

  • Documentation (PR #131): version references no longer hardcode the current release in the docs site -- rsigma.version now reads from Cargo.toml at build time via the macros plugin, so the docs auto-bump on every release rather than drifting behind. docs/guide/performance-tuning.md gains a "Rule loading at scale" section covering the v0.12.0 single-rebuild batched loaders and amortized O(1) add_rule with verified Criterion numbers at 1K / 10K / 100K rules. The rsigma-parser README intro paragraph's stale lint count (65) was bumped to 66 to match every other authoritative location.
  • Enrichment wording: the lookup enricher's startup error message and docs/guide/enrichers.md describe sources as "configured on the daemon" rather than "declared in your pipeline sources: block" so the copy stays accurate after a forthcoming release lets sources be declared independently of pipelines.
  • README and home page: Detection Engineering Weekly #157 added to the "featured in" list (README.md and docs/index.md) with a quote calling out RSigma's dynamic-pipelines model.
  • Contributing guidelines: the docs/ MkDocs site is now listed as a release deliverable in CONTRIBUTING.md alongside the crate READMEs, with a page-to-change matrix that maps each kind of change (new CLI flag, new daemon config key, new library API, new metric, new feature flag) to the page that must stay in sync.

v0.12.0...v0.13.0

0.12.0 - 2026-05-20🔗

TL;DR RSigma v0.12.0 is the "operability, performance, and documentation" release: * Comprehensive daemon and CLI observability: tower-http API access logs, per-request OTLP tracing, batch processing spans, source resolution spans, DLQ visibility, NATS and sink lifecycle events, correlation state eviction warnings, rule load diagnostics, daemon lifecycle logs, and a global --log-format flag for non-daemon subcommands. * Eval rule loading is no longer O(N²): Engine::add_rule is amortized O(1), and bulk loaders (Engine::add_rules, extend_compiled_rules, add_collection) rebuild indexes exactly once per batch. The full 3,120-rule SigmaHQ corpus that previously appeared to hang now loads in ~120 ms. * CLI subcommands reorganized into five noun-led groups (engine, rule, backend, pipeline). Flat aliases continue to work as deprecated forwarders for one release. * Full documentation site live at https://timescale.github.io/rsigma/: 47 pages spanning Getting Started, User Guide, CLI Reference, Library API, Developers, Reference (including a 66-rule lint catalogue and a 27-metric Prometheus catalogue), Deployment, Editors, and Ecosystem. Built from docs/ on every merge to main via the new .github/workflows/docs.yml. * Test reliability: cli_daemon_http and cli_daemon_otlp E2E suites are now flake-free on macOS under load. * Dependency bumps: opentelemetry-proto 0.31.0 to 0.32.0, async-nats 0.47 to 0.48, yamlpath/yamlpatch 1.25.2 (with the serde_yaml cargo rename replaced by yaml_serde directly), tokio 1.52.3, jsonschema 0.46.4, tower-http 0.6.10, tonic 0.14.6.

Daemon and CLI observability (PR #107)🔗

The daemon and CLI ship with structured logs, distributed tracing spans, and profiling hooks across the three observability pillars. All new instrumentation flows through the existing tracing-subscriber (JSON, env-filter) and is controlled via RUST_LOG. Spans are designed to be consumable by future tokio-console or tracing-opentelemetry exporters without code changes.

Phases. One commit per phase, in landing order:

Phase Scope
HTTP API access logs tower-http::TraceLayer::new_for_http() on the Axum router; each request produces a span with method, URI, status, and latency
Event pipeline Per-batch debug span (batch_size, input_format, match count, elapsed_ms); DLQ parse-failure debug events; checked DLQ channel send with warn-on-closed; DLQ task lifecycle logging
Source resolution InstrumentedResolver debug span (source_id, source_type); cache hit / fetch boundary events; refresh scheduler cycle completion logs (sources, duration_ms)
Correlation memory pressure Warn on hard-cap eviction (current count, max, evicted, target capacity) so high-cardinality traffic causing data loss is no longer silent
NATS, sinks, backpressure NATS source/sink publish and ack events; spawn_source backpressure warn alongside the existing metric; Sink::FanOut per-sink labels (sink_index, sink_type, error)
Rule load diagnostics load_rules info span (rules_path, duration_ms); first three parse error details when bad rules fail to compile
OTLP per-request tracing otlp_ingest debug span on both HTTP and gRPC handlers; record_count event after decoding ExportLogsServiceRequest
Daemon lifecycle Health state transitions; file watcher errors; reload-channel coalesce vs closed events; periodic state snapshot duration and serialized size; SQLite migration column events; per-task shutdown-join logs
--log-format for CLI Global --log-format <json\|text> initializes a stderr subscriber on non-daemon subcommands. engine eval, rule validate, and rule lint emit info events on completion (rules loaded, validation totals, lint summary) when a subscriber is installed. The daemon always logs JSON, so the flag is a no-op there.

Verbosity targets.

RUST_LOG filter Surfaces
info,tower_http=debug HTTP API access logs
info,rsigma=debug Batch processing spans, DLQ routing, OTLP per-request fields, snapshot save duration
info,rsigma_runtime::sources=debug Dynamic source resolution and refresh scheduler
info,rsigma_eval=debug Correlation engine internals

Span correctness fix. Holding an EnteredSpan guard from Span::enter() across .await is an anti-pattern on the multi-threaded tokio runtime: when the task is suspended, the thread-local span context can leak into other tasks scheduled on the same thread, producing incorrect span nesting. InstrumentedResolver::resolve, the OTLP HTTP and gRPC handlers, and the engine batch loop now use .instrument() on async blocks instead. Span fields, event payloads, and runtime behavior are unchanged.

Documentation. A new Observability section in the root README and an updated Logging paragraph in the CLI README list the supported RUST_LOG filter targets and document the new --log-format flag.

Eval rule loading performance (PRs #119, #121, #122, #123)🔗

Loading rules into an engine is no longer O(N²) in the rule count.

Batched loaders rebuild indexes exactly once. New Engine::add_rules (compiles each rule with the configured pipelines and collects per-rule compile errors without aborting the batch) and Engine::extend_compiled_rules (pre-compiled equivalent) rebuild the inverted index and per-field bloom exactly once at the end of the batch. Engine::add_collection, the rsigma rule validate path, and the rsigma engine eval rule load path now route through these APIs so the daemon and every RuntimeEngine caller share the one-rebuild fast path. Loading the SigmaHQ corpus (~3,120 rules) used to pay around 3K full index rebuilds and appeared to hang; it now completes in roughly 120 ms.

Single-rule add path is amortized O(1). Engine::add_rule and Engine::add_compiled_rule no longer rebuild the indexes from scratch on every push. They fold the new rule into the inverted index incrementally via the new RuleIndex::append_rule(rule_idx, rule) primitive, and into the per-field bloom via FieldBloomIndex::append_rule(rule). The bloom uses a doubling watermark with a 64-rule floor to schedule full rebuilds when the rule count has at least doubled past the last rebuild, capping false-positive-rate drift while keeping the amortized per-rule cost O(1). Rules that introduce a brand-new indexed field get a fresh bloom on the fly.

Rules add_collection add_rules add_rule loop
1,000 1.15 ms 1.17 ms 1.64 ms
10,000 11.82 ms 11.85 ms 17.23 ms
100,000 121.65 ms 122.13 ms 166.07 ms

(M4 Pro, release build. Run via cargo bench -p rsigma-eval --bench eval -- rule_load.)

When cross_rule_ac_enabled is on, the daachorse cross-rule index has no incremental update story, so the single-rule add path falls back to a full Engine::rebuild_index. Bulk loaders are unaffected.

Correctness. Between bloom rebuilds, probes may answer MaybeMatch where the batched-rebuild path would answer DefinitelyNoMatch. Both verdicts are correct (MaybeMatch is always safe); the engine just evaluates the rule directly instead of short-circuiting. The new differential test append_rule_matches_build_verdicts pins this property by checking that positive verdicts match exactly and that disjoint haystacks are still rejected at >= 90% under incremental builds.

Benchmarks. A new rule_load Criterion group compares the three load entry points at 1K / 10K / 100K rules. Numbers recorded in BENCHMARKS.md under the Rule Load Paths (0.11.x) subsection.

CLI command groups (PR #124)🔗

The 12 flat top-level subcommands are reorganized into five noun-led command groups so the CLI scales as more subcommands arrive. The flat aliases continue to work for one release as visible-deprecated forwarders, are hidden in the next release, and are removed in v1.0. Every existing invocation keeps working, so there is no breaking change in this release.

$ rsigma
Parse, validate, and evaluate Sigma detection rules

Usage: rsigma [OPTIONS] <COMMAND>

Commands:
  engine        Run rules against events (eval / daemon)
  rule          Inspect and operate on Sigma rule files
  backend       Convert Sigma rules to backend-native queries
  pipeline      Pipeline tooling (resolve dynamic sources, )
  attack        MITRE ATT&CK tooling (reserved; populated by the ATT&CK contributor PR)
  eval          [deprecated] Use `rsigma engine eval` instead
  daemon        [deprecated] Use `rsigma engine daemon` instead
  parse         [deprecated] Use `rsigma rule parse` instead
  validate      [deprecated] Use `rsigma rule validate` instead
  lint          [deprecated] Use `rsigma rule lint` instead
  fields        [deprecated] Use `rsigma rule fields` instead
  condition     [deprecated] Use `rsigma rule condition` instead
  stdin         [deprecated] Use `rsigma rule stdin` instead
  convert       [deprecated] Use `rsigma backend convert` instead
  list-targets  [deprecated] Use `rsigma backend targets` instead
  list-formats  [deprecated] Use `rsigma backend formats` instead
  resolve       [deprecated] Use `rsigma pipeline resolve` instead
  help          Print this message or the help of the given subcommand(s)

Options:
      --log-format <LOG_FORMAT>  Emit structured diagnostic logs to stderr (for CI / log aggregation) [possible values: json, text]
  -h, --help                     Print help (see more with '--help')
  -V, --version                  Print version

Migration:

Old (flat) New (grouped)
rsigma eval ... rsigma engine eval ...
rsigma daemon ... rsigma engine daemon ...
rsigma parse ... rsigma rule parse ...
rsigma validate ... rsigma rule validate ...
rsigma lint ... rsigma rule lint ...
rsigma fields ... rsigma rule fields ...
rsigma condition ... rsigma rule condition ...
rsigma stdin ... rsigma rule stdin ...
rsigma convert RULES ... rsigma backend convert RULES ...
rsigma list-targets rsigma backend targets
rsigma list-formats TARGET rsigma backend formats TARGET
rsigma resolve ... rsigma pipeline resolve ...

What you'll see. Invoking any flat alias prints one stderr line:

warning: `rsigma <old>` is deprecated; use `rsigma <new>` instead. This alias will be hidden in the next release and removed in v1.0.

stdout is unchanged. Exit codes are unchanged. Every flag accepted by the old form is accepted by the new form, with identical defaults and semantics.

Why noun-led groups. Every group is a noun (engine, rule, backend, pipeline), so command paths read as "rsigma's X tooling: do Y" rather than the awkward verb-on-verb chains a run or convert group would produce (rsigma convert run RULES vs the chosen rsigma backend convert RULES). The five groups are deliberately stable and small so future commands have an obvious home rather than landing as more top-level sprawl.

Deprecation timeline.

  • This release: flat aliases visible in rsigma --help with a [deprecated] tag, stderr warning on invocation. Every test, script, and pipeline keeps working.
  • Next release (issue #125): #[command(hide = true)] removes the aliases from --help but the invocations still work.
  • v1.0 (issue #126): flat aliases removed.

Internal refactor. The CLI dispatch layer is collapsed: each subcommand's clap arguments now live in crates/rsigma-cli/src/commands/<name>.rs as a pub struct <Name>Args deriving clap::Args, and the daemon's 35-field arg set + cmd_daemon body moved out of main.rs into a new crates/rsigma-cli/src/commands/daemon.rs. main.rs dropped from ~1360 lines to ~520 with no behavior change; the dispatch becomes a thin two-layer match (group -> leaf).

Documentation site (PR #129)🔗

A full documentation site now lives at https://timescale.github.io/rsigma/, built from docs/ with MkDocs Material and deployed by .github/workflows/docs.yml. 47 pages were written from scratch or migrated out of the README sprawl, structured so a detection engineer can get from "what is rsigma" to a running daemon in five minutes and to backend conversion or correlation in fifteen.

Sections.

Section Pages What it covers
Getting Started 3 Installation (cargo, Docker, signed binary archives), quick-start (first eval, first daemon, first convert in five minutes), core concepts (Sigma primer, rule kinds, eval-vs-daemon, noun-led CLI).
User Guide 11 Evaluating rules, streaming detection, rule conversion, linting, processing pipelines (static + dynamic), input formats (incl EVTX), NATS streaming, OTLP integration with copy-paste recipes for Grafana Alloy / Vector / Fluent Bit / OTel Collector, CI/CD, performance tuning (matcher optimizer, bloom, cross-rule AC), observability (--log-format, RUST_LOG filter targets).
CLI Reference 13 One page per grouped subcommand (engine eval, engine daemon, rule parse/validate/lint/fields/condition/stdin, backend convert/targets/formats, pipeline resolve) plus an overview with the migration table from the deprecated flat aliases.
Library 5 Per-crate overviews of rsigma-parser, rsigma-eval, rsigma-convert, rsigma-runtime, each with a verified minimum working example and the public API surface that matters for embedders.
Developers 6 Orientation, testing (the five-tier CI shape), fuzzing (all 15 cargo-fuzz harnesses), walkthroughs for adding a new backend, adding a new input format, and adding a new lint rule (the linter and LSP).
Reference 13 66-rule lint catalogue with worked examples for the trickier rules; PostgreSQL and LynxDB backend references; 27-metric Prometheus catalogue with verified labels; HTTP API; exit codes; environment variables; feature flags; custom attributes; builtin pipelines (ecs_windows, sysmon); dynamic-pipeline source spec; security hardening (input caps, resource limits, parser robustness, SQL injection prevention, network exposure, filesystem footprint, dependency policy); architecture diagram with the full crate map.
Deployment 1 Docker deployment with all hardening flags verified end-to-end against a rsigma:local build, including cosign signature verification and SLSA Build L3 attestation lookup via gh attestation.
Editors 2 VS Code / Cursor extension (wrapping rsigma-lsp); Neovim, Helix, Zed, Emacs eglot, and Sublime LSP wiring for the same server.
Ecosystem 1 Helr companion page with a full docker-compose stack pairing Helr's HTTP-API log collection with the rsigma daemon over NATS.
Top-level 5 Home (with a Built with RSigma section featuring detection.studio, a browser-based Sigma rule playground compiled from rsigma to WASM), Release Notes (mirrors this CHANGELOG), Contributing, Security Policy, Benchmarks (mirror of the root-level BENCHMARKS.md).

Verification. Every documented CLI flag, exit code, metric label, HTTP endpoint, environment variable, feature flag, and Docker hardening flag was checked against the live binary or the workspace source rather than transcribed from memory. The Docker page was tested end-to-end against a local rsigma:local build from main (compose stacks, bind-mount permissions, --state-db persistence, signature verification with cosign, SLSA attestation lookup via gh attestation).

CI. .github/workflows/docs.yml has a build job that runs mkdocs build --strict on every PR touching docs/, mkdocs.yml, or docs/requirements.txt, and a deploy job that runs only on main and publishes via actions/deploy-pages. Every action is SHA-pinned with a version comment; top-level permissions: {} with least-privilege per-job overrides (contents: read for build, pages: write + id-token: write for deploy); persist-credentials: false on checkout; concurrency group with cancel-in-progress; workflow_dispatch for manual dry-runs. zizmor --pedantic reports zero findings.

One-time setup. GitHub Pages source must be set to "GitHub Actions" under Settings -> Pages. The first push to main after the v0.12.0 release does the first deploy; subsequent docs-only changes redeploy automatically.

Deferred. The Kubernetes deployment page is staged under docs-drafts/ until the Helm Chart (#1a roadmap item) lands. The attack CLI subcommand group has a reserved enum but no docs yet; documentation will arrive with the MITRE ATT&CK contributor PR.

Test reliability (PRs #115, #123)🔗

The cli_daemon_http and cli_daemon_otlp E2E suites are no longer flaky on macOS under load. Three real issues caused intermittent ConnectionRefused:

  1. The daemon's stdout was piped but never drained, so a chatty detection-match sink could fill the ~64 KiB pipe buffer and stall the daemon mid-write.
  2. The spawn handshake stopped reading stderr after seeing "Sink started", so any subsequent log line could fill the stderr buffer too.
  3. "Sink started" is emitted before axum::serve enters its accept loop; tests that fired requests immediately after the handshake sometimes hit the kernel before the listener was wired up.

The shared DaemonProcess helper (now in tests/common/mod.rs) drains stdout in a background thread, forwards interesting stderr lines to the main thread via mpsc, probes the actual TCP socket with TcpStream::connect_timeout before returning, and wraps the Child in a ChildGuard RAII type. Fixed std::thread::sleep waits in three OTLP tests and two HTTP tests are replaced with a poll_until helper that retries every 50 ms up to a 5 s deadline against the specific observable condition (metric labels present, status counters incremented). Each test now finishes in around 1.0 s, with the suite passing consistently across many consecutive macOS runs.

PR #123 also de-flaked an eval bloom test (append_rule_matches_build_verdicts) by replacing brittle three-needle assertions with a 1000-trigram aggregate sweep, since BuildHasherDefault<ahash::AHasher> uses a runtime-randomized seed by default and bit positions shift between process invocations.

Other changes🔗

  • Dependencies (PRs #111, #113, #114, #120): opentelemetry-proto 0.31.0 -> 0.32.0 with handling for the new StringValueStrindex and key_strindex schema fields; async-nats 0.47 -> 0.48 (JetStream 2.14 features, panic fix); jsonschema 0.46.3 -> 0.46.4 (regex panic fix); tower-http 0.6.9 -> 0.6.10; tonic 0.14.5 -> 0.14.6; tokio 1.52.2 -> 1.52.3. yamlpath and yamlpatch bumped to 1.25.2, and the serde_yaml cargo rename was replaced with the real yaml_serde crate name across all six member manifests (~199 source references), so the manifest, source code, and compiler errors agree about which crate is in use.
  • GitHub Actions (PRs #111, #120): taiki-e/install-action 2.75.28 -> 2.77.3, github/codeql-action 4.35.2 -> 4.35.4, sigstore/cosign-installer 4.1.1 -> 4.1.2.
  • Dependabot config (PR #114): added a second cargo ecosystem entry pointed at /fuzz with the same weekly schedule and patch group as the root entry, so the fuzz workspace's lockfile no longer drifts and bleeds into unrelated PRs.
  • Architecture diagrams: the ASCII diagram in README.md and the Mermaid diagram in assets/architecture.mmd were refreshed to reflect Dynamic Sigma Pipelines (v0.10.0), the matcher optimizer and prefilters (v0.11.0), DLQ as a sink target, broadened hot-reload over rules + pipelines, builtin pipelines (ecs_windows, sysmon), and the directory-style modules from the v0.9.0 modularization. A legend now explains feature-gated components (* for feature-gated and ** for daachorse-index).
  • README: install and build instructions corrected; eval prefilters mentioned in the prose; fifth blog article and BlackNoise newsletter mention added.

v0.11.0...v0.12.0

0.11.0 - 2026-05-14🔗

TL;DR RSigma v0.11.0 is the "eval performance" release: * Matcher optimizer: batches |contains lists into Aho-Corasick automata, groups sibling regex matchers into RegexSet DFAs, and eliminates redundant to_lowercase() calls via shared case-folding groups. * Opt-in bloom filter pre-filtering for substring matchers, skipping entire detection items when trigrams cannot match. * Opt-in cross-rule Aho-Corasick prefilter via daachorse (behind the daachorse-index feature flag), pruning entire rules before evaluation with up to ~100x speedup on substring-heavy workloads. * Security hardening for dynamic pipeline sources: 10 MB body/payload caps on HTTP, command stdout, and NATS; 30-second command execution timeout; 1-second refresh interval floor. Closes all v0.10.0 Known Limitations. * Parser fix: the unsupported |not modifier is now rejected with guidance toward condition-level negation. * Dependency bumps: criterion 0.5.1 to 0.8.2, jsonschema 0.42.2 to 0.46.3.

Matcher optimizer (PRs #99, #100, #101, #105)🔗

The compiler now includes an optimization pass that restructures AnyOf matcher trees for better runtime performance. The optimizer is always on and preserves evaluation semantics exactly. Three transformations are applied in order:

Aho-Corasick batching. When an AnyOf node contains 8 or more plain |contains children with the same case sensitivity, they are collapsed into a single Aho-Corasick automaton (AhoCorasickSet). Instead of N sequential substring scans, the engine makes one linear pass over the haystack. The threshold of 8 was chosen empirically from a benchmark sweep: below 8 patterns, sequential str::contains with SIMD acceleration (memchr / Two-Way) is faster; at 8 and above, throughput flattens because the AC automaton scans once regardless of pattern count.

Patterns h=100 B h=1 KB h=8 KB h=64 KB
1 13.0 Melem/s 7.77 Melem/s 1.85 Melem/s 248 Kelem/s
4 9.08 Melem/s 2.03 Melem/s 293 Kelem/s 35.6 Kelem/s
8 5.17 Melem/s 620 Kelem/s 79.0 Kelem/s 9.76 Kelem/s
16 5.19 Melem/s 628 Kelem/s 78.6 Kelem/s 9.67 Kelem/s
32 4.99 Melem/s 607 Kelem/s 76.4 Kelem/s 8.88 Kelem/s

RegexSet batching. When an AnyOf node contains 3 or more |re children, they are collapsed into a single RegexSet DFA. One DFA pass replaces N independent regex evaluations. Falls back to individual matchers if set construction fails.

Case-insensitive grouping. After AC and RegexSet restructuring, if 2 or more surviving children are all case-insensitive and "pre-lowerable," they are wrapped in a CaseInsensitiveGroup. The haystack is lowered once via ascii_lowercase_cow (borrow-if-already-lower fast path), and all children use matches_pre_lowered against the shared lowered string, eliminating repeated allocation.

The optimizer only applies to AnyOf (OR) groups, never to AllOf (AND). This is a correctness constraint: collapsing AND-of-contains into AC with any-match semantics would change the logic.

Correctness guarantee. A new differential fuzz target (fuzz_eval_matcher_diff) asserts that optimize_any_of(matchers) produces identical match results to AnyOf(matchers) for arbitrary needle sets, haystacks, and case sensitivity.

Bloom filter pre-filtering (PRs #102, #104)🔗

An opt-in trigram-based bloom index that can skip expensive substring matching before it starts. The bloom filter operates at the detection-item level, inside evaluate_rule.

How it works. At rule load time, the engine extracts positive substring needles (|contains, |startswith, |endswith, and AhoCorasickSet needles) from all compiled rules and inserts every 3-byte trigram into a per-field bloom filter (double hashing from AHash-derived pairs). At eval time, for each string field value, the engine slides trigrams over the lowered haystack; if no trigram from any pattern is present in the bloom, the item returns DefinitelyNoMatch and the matcher is skipped entirely.

One-sided correctness. The bloom filter has no false negatives for "definitely no match." If it says MaybeMatch, the full matcher runs as usual. Negated branches, non-string fields, and short/huge values conservatively return MaybeMatch.

Memory budget. Default total budget is 1 MiB (DEFAULT_MAX_TOTAL_BYTES), with a 64 KiB per-field cap. If the total exceeds the budget, fields with the worst bits-per-pattern density are dropped first. The budget is configurable via Engine::set_bloom_max_bytes.

CLI flags.

rsigma eval -r rules/ -e @events.json --bloom-prefilter
rsigma eval -r rules/ -e @events.json --bloom-prefilter --bloom-max-bytes 131072

rsigma daemon -r rules/ --bloom-prefilter
rsigma daemon -r rules/ --bloom-prefilter --bloom-max-bytes 2097152

When to enable. The bloom index adds approximately 1 microsecond of per-event trigram probing overhead. It pays off when you have many substring-heavy rules and most events do not match (the common case for threat intel feeds against high-volume telemetry). Benchmark with your own data before enabling in production.

Cross-rule Aho-Corasick prefilter (PR #106)🔗

An opt-in whole-rule prefilter that prunes entire rules before evaluate_rule runs. This is distinct from the per-item matcher optimizer and the per-item bloom filter: it operates at the rule level.

How it works. At index build time, the engine collects all positive substring needles (lowered) from every rule and builds one DoubleArrayAhoCorasick<u32> automaton per field using the daachorse crate. Pattern IDs map back to rule indices. At eval time, for each indexed field with a string value, one overlapping scan on the lowered haystack marks which rules had at least one pattern hit. Rules that are "AC-prunable" (all detections consist exclusively of positive substring matchers, no negation in conditions, no field-less keywords) and received zero hits are skipped entirely.

Benchmark results. 200 non-matching events against N pure-substring rules (best-case workload):

Rules Off (default) On (--cross-rule-ac) Speedup
1,000 17.34 ms (11.5 Kelem/s) 253.0 us (790 Kelem/s) ~68x
5,000 85.51 ms (2.34 Kelem/s) 883.0 us (226 Kelem/s) ~97x
10,000 173.37 ms (1.15 Kelem/s) 1.71 ms (117 Kelem/s) ~101x

The cross-rule index turns O(rules x patterns) per event into O(haystack_length) for the AC scan, so throughput is essentially constant in rule count.

Feature flag. The daachorse dependency is optional and gated behind the daachorse-index Cargo feature. Build with:

cargo install rsigma --features daachorse-index
# or
cargo build --release --features daachorse-index

CLI flags.

rsigma eval -r rules/ -e @events.json --cross-rule-ac
rsigma daemon -r rules/ --cross-rule-ac

When to enable. This is off by default. For typical mixed workloads (substring + exact + regex rules, events that hit multiple fields, smaller rule sets), the index adds build-time and lookup overhead with smaller wins or none, and can cause a slowdown. Enable for large (5K+ rules), substring-heavy, shared-pattern packs where most events do not match. Always benchmark against representative data first.

Composition. The three prefilter layers stack: the rule index narrows by exact field values, the cross-rule AC narrows by substring patterns, and the bloom filter skips individual detection items. All three can be enabled simultaneously; regression tests assert that the combined output matches the no-prefilter baseline.

Security hardening for dynamic pipeline sources (PR #96)🔗

This release closes all four items listed under "Known Limitations" in the v0.10.0 release notes. Dynamic pipeline sources that fetch from HTTP, command, or NATS now enforce resource limits.

HTTP response body size limit. Responses are capped at 10 MB (MAX_SOURCE_RESPONSE_BYTES). If the server advertises a Content-Length exceeding the limit, the response is rejected without buffering the body. During streaming, if the accumulated body exceeds the limit, the connection is dropped. A 30-second client timeout is also enforced.

Command execution timeout and stdout size limit. Command sources are killed after 30 seconds (DEFAULT_COMMAND_TIMEOUT). Stdout is read in 8 KB chunks and capped at 10 MB; exceeding the limit kills the child process. Stderr is separately capped at 64 KB to prevent a chatty failing command from exhausting memory.

NATS message payload size limit. NATS messages exceeding 10 MB are rejected before parsing.

Refresh interval floor. Source refresh intervals below 1 second are clamped to 1 second with a structured warning log. This prevents config mistakes or hostile configs from causing tight polling loops.

All limits use a new SourceErrorKind::ResourceLimit variant with descriptive messages. Integration tests validate timeout killing, stdout size rejection, and NATS payload rejection.

Parser: reject |not modifier (PR #103)🔗

Writing field|not: value in a Sigma rule is a common mistake. The not keyword is a condition-level operator, not a value modifier. Previously this would produce a generic "unknown modifier" error. Now the parser returns a dedicated NotIsNotAModifier error with guidance:

not is not a value modifier in Sigma; express negation in the condition (e.g. not selection) or move the inverted check into a separate detection used as a filter (e.g. selection and not other)

Regression test suite (PRs #105, #106)🔗

A new regression_eval.rs test file (459 lines) locks down optimizer and prefilter correctness with differential tests:

Test What it validates
baseline_contains_heavy_corpus Multi-rule contains-heavy corpus produces expected match sets
allof_contains_semantics_preserved \|contains\|all requires all needles (not collapsed to AC with OR semantics)
keyword_aho_corasick_path_correct Field-less keywords: block with enough terms to hit AC path
bloom_prefilter_preserves_match_results Bloom on vs off produces identical results
bloom_prefilter_handles_condition_negation not other with \|contains under bloom short-circuit
optimizer_runs_after_pipeline_transformation Pipeline maps field names before optimizer runs
cross_rule_ac_preserves_match_results Cross-rule AC on vs off produces identical results
cross_rule_ac_handles_condition_negation not other with cross-rule AC
cross_rule_ac_composes_with_bloom All three prefilters enabled together match the baseline

Benchmarks (PRs #105, #106)🔗

Five new Criterion benchmark groups with dedicated data generators:

Group What it measures
eval_contains_heavy 1-200 \|contains patterns per rule, 1000 events
eval_ac_threshold_sweep Pattern counts 1-32 across haystack lengths 100 B to 64 KB
eval_regex_set_heavy 3-50 wildcard patterns per rule via RegexSet
eval_bloom_rejection 100-5000 substring-only rules with guaranteed non-matching events, bloom on vs off
eval_cross_rule_ac 1K-10K substring-only rules with non-matching events, cross-rule AC on vs off

Results are recorded in BENCHMARKS.md.

Other changes🔗

  • Stale warning fix (PR #98): replaced the Phase 1 placeholder warning for dynamic pipelines with the correct message now that the feature is complete.
  • Rustdoc (PR #106): surfaced Engine::set_bloom_prefilter, Engine::set_bloom_max_bytes, Engine::set_cross_rule_ac, and SigmaParserError::NotIsNotAModifier in public documentation.
  • criterion migration (PR #95): bumped criterion from 0.5.1 to 0.8.2; replaced deprecated criterion::black_box with std::hint::black_box across all benchmark files.
  • jsonschema bump (PR #94): bumped jsonschema from 0.42.2 to 0.46.3.
  • VS Code extension (PR #97): bumped fast-uri from 3.1.0 to 3.1.2 (Dependabot).
  • README link: added link to the fourth blog article.

v0.10.0...v0.11.0

0.10.0 - 2026-05-08🔗

TL;DR RSigma v0.10.0 is the "dynamic pipelines" release: * Dynamic Sigma Pipelines: declare HTTP, command, file, and NATS sources inside pipeline YAML, with template expansion, include directives, TTL caching, background refresh, and three extract languages (jq, JSONPath, CEL). * A new rsigma resolve CLI command and full daemon integration with Prometheus instrumentation. * Native EVTX input: evaluate Sigma rules directly against Windows Event Log binary files. * Pipeline hot-reload: the daemon now watches pipeline files alongside rules. * Builtin pipelines: ecs_windows and sysmon embedded at compile time. * Comprehensive fuzz testing: 14 cargo-fuzz harnesses covering all untrusted input surfaces. * Security hardening: SQL injection prevention, recursion limits, condition DoS caps, SIGTERM handler, and event size limits. * CI and supply chain: MSRV enforcement, cargo-deny, serde_yaml migration, Dependabot, SECURITY.md, and CONTRIBUTING.md.

Dynamic Sigma Pipelines (PRs #86-#93)🔗

Pipelines can now declare external data sources that are resolved at runtime and injected into pipeline fields via template expansion. This is a capability unique to RSigma: no other Sigma engine supports dynamic processing pipelines.

Four source types. A new sources section in pipeline YAML declares named data sources:

sources:
  threat_intel:
    type: http
    url: https://feeds.example.com/iocs.json
    format: json
    extract:
      expr: ".indicators[].value"
      type: jsonpath
    refresh:
      interval: 300
    on_error: use_cached
    required: false
Source type Description
http Fetch from a URL (GET/POST) with optional headers
command Execute a local command and capture stdout
file Read from a local file path
nats Subscribe to a NATS subject for push-based updates

Template expansion. Pipeline field values reference resolved source data via ${source.threat_intel} syntax. Templates are expanded after all sources resolve, before the pipeline is applied to rules.

Three extract languages. Source responses can be filtered before injection:

Type Engine Example
jq (default) jaq .records[] \| .ip
jsonpath jsonpath-rust $.indicators[*].value
cel cel-interpreter data.filter(x, x.severity > 3)

Include directives. Pipelines can include other pipeline fragments via include sources, with a recursive depth limit of 1. Remote includes (HTTP, NATS) require the --allow-remote-include daemon flag.

TTL-based caching. Resolved source data is cached in SQLite with configurable TTL. A cache invalidation API allows on-demand refresh without waiting for expiry.

Background refresh. After startup, sources refresh on their configured interval in the background. Failures for non-required sources do not block the pipeline; the last cached value is used (configurable via on_error: use_cached | fail | ignore).

SIGHUP re-resolution. Sending SIGHUP to the daemon triggers both a rule reload and a full source re-resolution cycle.

NATS control subject. A NATS message on a configurable control subject triggers source re-resolution, enabling external orchestration of pipeline updates.

rsigma resolve command (PR #88). A new CLI subcommand resolves dynamic sources and prints results:

rsigma resolve -p pipelines/dynamic_threat_intel.yml
rsigma resolve -p pipelines/dynamic_threat_intel.yml -s threat_intel --pretty
rsigma resolve -p pipelines/dynamic_threat_intel.yml --dry-run

rsigma validate --resolve-sources (PR #88). Validate that pipeline sources can be resolved successfully alongside rule validation.

Prometheus metrics (PR #88). Five new metrics track source resolution in the daemon:

Metric Labels Description
rsigma_source_resolves_total source_id, source_type Total source resolution attempts
rsigma_source_resolve_errors_total source_id, error_kind Resolution errors by kind (Fetch, Parse, Extract, Timeout)
rsigma_source_resolve_seconds Resolution latency histogram
rsigma_source_cache_hits_total Cache hit counter
rsigma_source_last_resolved_timestamp source_id Unix timestamp of last successful resolution

/api/v1/status extension (PR #88). The status endpoint now includes a dynamic_sources summary when sources are configured:

{
  "status": "running",
  "dynamic_sources": {
    "total": 3,
    "resolves_total": 42,
    "errors_total": 1,
    "cache_hits": 38
  }
}

Full test coverage. Integration and E2E tests validate the entire dynamic pipeline lifecycle against real daemon instances (PR #90). Criterion benchmarks measure resolution throughput and template expansion overhead (PR #91). Seven dedicated fuzz targets cover source YAML parsing, template expansion, extract expressions, include parsing, and HTTP response handling (PR #92). SigmaHQ corpus regression validates that dynamic pipelines do not regress existing static pipeline behavior (PR #93).

EVTX input adapter (PR #85)🔗

RSigma can now evaluate Sigma rules directly against Windows Event Log binary files (.evtx). The adapter uses the evtx crate to parse the binary format and yield JSON records that feed directly into the detection engine.

rsigma eval -r rules/windows/ -e @Security.evtx
rsigma eval -r rules/ -p sysmon -e @Microsoft-Windows-Sysmon%4Operational.evtx

Auto-detection is extension-based: any @path argument ending in .evtx (case-insensitive) is routed through the EVTX parser. The feature is compile-time gated behind the evtx feature flag (included in default features).

Pipeline hot-reload (PR #68)🔗

The daemon file watcher now monitors pipeline YAML files alongside the rules directory. Changes to any referenced pipeline file trigger the same debounced reload cycle as rule changes:

  1. Filesystem events on watched .yml/.yaml files (500 ms debounce)
  2. SIGHUP signal (Unix)
  3. POST /api/v1/reload endpoint

If a pipeline file fails to parse during reload, the old engine configuration is preserved and rsigma_reloads_failed_total is incremented.

Builtin pipelines (ecs_windows, sysmon) are embedded at compile time and excluded from the file watcher.

Bundled pipelines (PR #69)🔗

Two processing pipelines are now embedded in the binary via include_str!():

Name Description
ecs_windows Sigma/Sysmon field names to Elastic Common Schema (process creation, network, file, registry, DNS, pipe, driver, remote thread, process access)
sysmon Adds EventID conditions for logsource-to-Sysmon-event routing

Reference them by name instead of a file path:

rsigma eval -r rules/ -p ecs_windows -e @events.json
rsigma daemon -r rules/ -p sysmon
rsigma convert -r rules/ -t postgres -p ecs_windows

Fuzz testing (PR #70, PR #92)🔗

Fourteen cargo-fuzz harnesses now cover every untrusted input surface:

Target Surface
fuzz_parse_yaml Sigma YAML parser
fuzz_condition Condition expression parser
fuzz_field_modifiers Field modifier parsing
fuzz_eval_matching Event evaluation engine
fuzz_regex_compile Regex pattern compilation
fuzz_pipeline_yaml Pipeline YAML parsing
fuzz_input_formats Input format auto-detection (JSON, syslog, logfmt, CEF)
fuzz_pipeline_sources_yaml Dynamic source YAML parsing
fuzz_extract_jq jq extract expression evaluation
fuzz_extract_jsonpath JSONPath extract expression evaluation
fuzz_extract_cel CEL extract expression evaluation
fuzz_template_expand Template ${source.*} expansion
fuzz_include_parse Include directive parsing
fuzz_http_response HTTP response body handling

Seed corpora include real SigmaHQ rules, handcrafted adversarial inputs, and valid pipeline examples. A weekly scheduled CI job runs all targets with per-target --max_len limits. Crashes upload as artifacts.

Security hardening (PRs #71-#76)🔗

Six PRs address security, robustness, and code quality:

SQL injection prevention (PR #71). The PostgreSQL backend now validates all identifiers (table, schema, field segments) against ^[A-Za-z_][A-Za-z0-9_$]*$ before embedding them in SQL. Malicious inputs are rejected with ConvertError::InvalidIdentifier instead of being interpolated.

Unbounded recursion limits (PR #71). YAML deep-merge is capped at 64 levels (MAX_DEPTH). Exceeding the limit returns SigmaParserError::MergeTooDeep.

Condition DoS caps (PR #71). Condition expressions are limited to 64 KiB (MAX_CONDITION_LEN) and 64 nesting levels (MAX_CONDITION_DEPTH). Both limits return descriptive parse errors instead of stack overflow.

SIGTERM handler (PR #74). The daemon now handles SIGTERM with the same graceful shutdown path as Ctrl+C: drain the pipeline within --drain-timeout, persist correlation state, and exit cleanly.

parking_lot mutexes (PR #74). Internal mutexes migrated from std::sync::Mutex to parking_lot::Mutex for fairer scheduling and no poisoning.

Event size cap (PR #74). HTTP ingestion rejects individual lines exceeding 1 MiB with 413 Payload Too Large.

Code quality (PR #75). KEY_CACHE completeness test ensures all modifier keys are cached. partial_cmp replaced with total_cmp for deterministic float comparisons.

Testing gaps (PR #76). Runtime integration tests and parser AST snapshot tests added to cover previously untested paths.

CI and supply chain (PRs #72-#73)🔗

MSRV enforcement. A dedicated CI job runs cargo check --workspace --all-features --locked on the declared MSRV (1.88.0).

cargo-deny. Advisory database checking and license scanning via cargo-deny in CI. Known advisory RUSTSEC-2021-0153 (evtx transitive dep on encoding) is documented and allow-listed.

serde_yaml migration. All crates migrated from the unmaintained serde_yaml to yaml_serde 0.10.4 via Cargo package renaming, with zero source-level changes required.

Dependabot (PR #84). Automated dependency updates enabled; all flagged dependencies bumped in a single batch.

SECURITY.md and CONTRIBUTING.md (PR #73). Security disclosure policy and contribution guidelines added to the repository root.

Other changes🔗

  • --dry-run for rsigma resolve: inspect source metadata (type, refresh policy, required flag) without performing actual resolution.
  • Cross-platform command source tests: Windows-compatible assertions for command-type dynamic sources.
  • MSRV 1.88.0 type inference fix: explicit type annotations for prometheus with_label_values calls to satisfy the minimum supported Rust version.
  • CI: removed semver-checks job: semver compatibility checking removed from the CI pipeline (was producing false positives on internal API changes).
  • Benchmark documentation: full Criterion benchmark results recorded across all crates.
  • README updates: dynamic pipelines documented across root, rsigma-cli, and rsigma-runtime READMEs.

Known Limitations🔗

Dynamic pipeline sources that fetch from HTTP, NATS, or command execution do not yet enforce resource limits on response size, execution timeout, or refresh interval. Specifically: - HTTP responses are read to completion without a body size cap - Command sources inherit the daemon process timeout but lack a per-source timeout enforcement - NATS push sources do not cap payload size - No minimum floor on refresh interval (a very short interval could cause excessive load)

These hardening items are tracked as a roadmap item and will either ship in v0.10.1 or in v0.11.0. The feature is opt-in (sources must be explicitly declared in pipeline YAML by the operator), and the critical injection/recursion/DoS vectors are already addressed in this release.

v0.9.0...v0.10.0

0.9.0 - 2026-05-04🔗

TL;DR RSigma v0.9.0 is one of the largest releases yet: * Production-grade NATS JetStream with at-least-once delivery, authentication and TLS, dead-letter queues, replay from offset or timestamp, consumer groups, and sequence-aware correlation state restoration * Native OpenTelemetry log ingestion over HTTP (protobuf + JSON) and gRPC * A new LynxDB conversion backend for SPL2-compatible queries * The rsigma fields field catalog * Structured exit codes for CI/CD scripting * Per-rule Prometheus metric labels * The entire codebase restructured into directory-based modules * And a comprehensive E2E test suite validating every I/O path against real Postgres and NATS instances via testcontainers

NATS production hardening (PR #59)🔗

Five features bring the NATS pipeline from development-grade to production-ready.

At-least-once delivery with deferred ack. The streaming pipeline has been refactored from at-most-once to at-least-once delivery. Messages are now held in an AckToken until the sink confirms delivery. A new RawEvent struct bundles each payload with its ack token, and a dedicated ack task resolves tokens after sink confirmation. If the daemon crashes before ack, NATS redelivers the message after ack_wait expires. The EventSource trait now returns Option<RawEvent> instead of Option<String>, and NatsSink has been upgraded from core NATS publish to JetStream publish with server-confirmed persistence.

Authentication and TLS. A new NatsConnectConfig struct supports credentials file, token, username/password, NKey, mutual TLS (client cert + key), and require-TLS. Auth methods are mutually exclusive; the first configured one wins. Sensitive values can also be read from environment variables.

CLI flag Environment variable Description
--nats-creds NATS_CREDS Credentials file path
--nats-token NATS_TOKEN Authentication token
--nats-user / --nats-password NATS_USER / NATS_PASSWORD Username and password
--nats-nkey NATS_NKEY NKey seed
--nats-tls-cert / --nats-tls-key Client certificate and key for mutual TLS
--nats-require-tls Require TLS on the connection

Dead-letter queue. Events that fail processing are routed to a configurable DLQ instead of being silently discarded. The --dlq flag accepts the same URL schemes as --output (stdout://, file://, nats://). Each DLQ entry is a JSON object containing original_event, error, and timestamp. Integration points: parse errors detected before engine processing and sink delivery failures. A new rsigma_dlq_events_total Prometheus counter tracks DLQ volume.

rsigma daemon -r rules/ --input nats://localhost:4222/events.> --dlq file:///var/log/rsigma-dlq.ndjson
rsigma daemon -r rules/ --input nats://localhost:4222/events.> --dlq nats://localhost:4222/dlq.rsigma

Replay from offset or timestamp. A ReplayPolicy enum (Resume, FromSequence, FromTime, Latest) controls the JetStream consumer's starting position. Three mutually exclusive CLI flags set the policy. Correlation state restoration is handled intelligently based on the replay direction (see "Smart correlation state restoration" below).

rsigma daemon -r rules/ --input nats://localhost:4222/events.> --replay-from-sequence 42
rsigma daemon -r rules/ --input nats://localhost:4222/events.> --replay-from-time 2026-04-30T00:00:00Z
rsigma daemon -r rules/ --input nats://localhost:4222/events.> --replay-from-latest

Consumer groups for horizontal scaling. The --consumer-group flag sets a shared durable consumer name across multiple daemon instances. All instances using the same group name pull from a single JetStream consumer, and NATS automatically distributes messages for load balancing. When not specified, the consumer name is auto-derived from the subject (existing behavior).

rsigma daemon -r rules/ --input nats://localhost:4222/events.> --consumer-group detection-workers

Smart correlation state restoration (PR #61)🔗

The daemon now makes intelligent decisions about whether to restore correlation state from SQLite when restarting with a replay flag. Previously, any non-Resume replay policy unconditionally cleared correlation state to avoid double-counting. This was correct for forensic replay but overly conservative for forward catch-up scenarios where the daemon shuts down and restarts with --replay-from-sequence pointing after the last processed event.

Sequence-aware auto-restore. The daemon now tracks the NATS JetStream stream sequence and published timestamp of the last acknowledged message. This SourcePosition is stored alongside the correlation snapshot in SQLite (two new columns added via automatic schema migration). On restart, the decide_state_restore function compares the replay start point against the stored position: if the replay starts after the stored position (forward catch-up), state is restored safely; if at or before (backward replay), state is cleared to prevent double-counting.

Explicit overrides. Two new mutually exclusive CLI flags give operators direct control when the automatic decision is not appropriate:

Flag Behavior
--keep-state Always restore correlation state, regardless of replay policy
--clear-state Always clear correlation state and start fresh
(neither) Automatic decision based on replay direction and stored position
rsigma daemon -r rules/ --input nats://localhost:4222/events.> --replay-from-sequence 1001 --state-db state.db
rsigma daemon -r rules/ --input nats://localhost:4222/events.> --replay-from-sequence 1 --state-db state.db
rsigma daemon -r rules/ --input nats://localhost:4222/events.> --replay-from-sequence 1 --state-db state.db --keep-state

Timestamp fallback control. A new --timestamp-fallback flag (wallclock or skip) controls how correlation windows handle events without parseable timestamp fields. The default wallclock substitutes the current time (existing behavior). The new skip mode causes detections to still fire but omits the event from correlation state updates, preventing wall-clock times from corrupting temporal windows during forensic replay of historical logs.

rsigma daemon -r rules/ --input nats://localhost:4222/events.> --timestamp-fallback skip

Automatic schema migration. Existing SQLite state databases are transparently migrated on first open. The migration adds the source_sequence and source_timestamp columns without losing the existing correlation snapshot.

Codebase modularization (PRs #46-#58)🔗

Thirteen PRs systematically split 12 large single-file modules into directory-based module structures across all six crates, improving navigability and reducing merge conflicts. The refactoring is purely structural with no behavioral changes.

PR File Result
#46 lint.rs (4,991 lines) lint/{mod,rules/{metadata,detection,correlation,filter,shared}}.rs
#47 main.rs (2,221 lines) commands/{parse,validate,lint,eval,convert}.rs
#48 postgres.rs (3,183 lines) postgres/{mod,correlation,tests}.rs
#49 correlation_engine.rs (4,395 lines) correlation_engine/{mod,types,tests}.rs
#50 transformations.rs (3,379 lines) pipeline/transformations/{mod,helpers,tests}.rs
#51 parser.rs (2,276 lines) parser/{mod,detection,correlation,filter,tests}.rs
#52 pipeline/mod.rs (2,235 lines) pipeline/{mod,parsing}.rs
#53 compiler.rs (1,824 lines) compiler/{mod,helpers,tests}.rs
#54 correlation.rs (1,781 lines) correlation/{mod,types,buffers,compiler,keys,window,tests}.rs
#55 engine.rs (1,656 lines) engine/{mod,filters,tests}.rs
#56 matcher.rs (1,118 lines) matcher/{mod,matching,helpers}.rs
#57 event.rs (758 lines) event/{mod,json,kv,plain,map}.rs
#58 cli/tests/cli.rs (1,745 lines) tests/{cli_parse,cli_validate,cli_lint,cli_eval,cli_daemon,common/mod}.rs

Additional cleanup: is_valid_uuid was de-duplicated across lint rule modules, and pipeline parsing logic was extracted from mod.rs into its own submodule.

E2E test suite (PR #60)🔗

A comprehensive end-to-end test suite validates every major I/O path against real infrastructure. All container-based tests use testcontainers and are automatically skipped when Docker is unavailable.

PostgreSQL integration tests. Convert Sigma rules to SQL and execute the generated queries against a real PostgreSQL instance. Uses the Okta cross-tenant impersonation scenario with JSONB schema, 6 sample events, and 4 SigmaHQ detection rules. Tests cover default format, VIEW creation, multi-rule conversion, event_count correlation, and the no-match case.

NATS E2E tests (binary-level). Spawn the rsigma daemon as a child process with --input/--output NATS URLs pointed at a testcontainers NATS instance. Four tests cover single detection, no-match silence, event_count correlation, and fan-out to multiple output subjects.

NATS E2E tests (library-level). Additional integration tests in rsigma-runtime covering JetStream publish/subscribe, detection routing, and the article scenarios from the companion blog series.

HTTP daemon E2E tests. Spawn the daemon with --input http and --api-addr 127.0.0.1:0, discover the ephemeral port from structured log output, and exercise all REST endpoints: healthz, readyz, metrics, rules, status, reload, and POST /api/v1/events with single and batch NDJSON payloads.

Input format tests. CLI-level tests for syslog, plain text, and auto-detect input formats on both the daemon and eval commands.

Snapshot-based convert tests. Integration tests for the convert subcommand that compare CLI output against expected snapshots.

The state restore feature adds 10 additional E2E tests (6 HTTP-based, 4 NATS-based with testcontainers) covering --clear-state, --keep-state, --timestamp-fallback, schema migration, and sequence-aware forward/backward replay.

In total, roughly 4,700 lines of integration tests across 10 new test files, plus 850 lines of NATS-specific tests in rsigma-runtime.

OTLP log ingestion (PR #64)🔗

Native OpenTelemetry Protocol (OTLP) log receiver for the daemon. Three transports feed into a shared conversion layer that flattens each OTLP LogRecord (merged with parent Resource and InstrumentationScope attributes) into a JSON event and routes it through the detection engine.

OTLP/HTTP. POST /v1/logs accepts both protobuf (application/x-protobuf) and JSON (application/json) encoding. When Content-Encoding: gzip is present, the body is decompressed before decoding. Protobuf is assumed when no Content-Type is provided, matching the OTLP/HTTP specification default.

OTLP/gRPC. LogsService/Export is registered via tonic and multiplexed with the existing Axum REST endpoints on the same --api-addr port using accept_http1(true), so HTTP/1.1 REST clients and HTTP/2 gRPC clients share a single listener.

Prometheus metrics. Three new counters track OTLP traffic:

Metric Labels Description
rsigma_otlp_requests_total transport, encoding OTLP export requests received
rsigma_otlp_log_records_total Log records ingested via OTLP
rsigma_otlp_errors_total transport, reason OTLP request errors

Feature gating. OTLP is compile-time gated behind the daemon-otlp feature flag (not in default features). Build with cargo build --features daemon-otlp. When enabled, OTLP endpoints are always active alongside any --input mode.

rsigma daemon -r rules/ --input http --api-addr 0.0.0.0:9090

Tests: 9 integration tests covering HTTP protobuf, JSON, gzip, error cases (415 unsupported content type, 400 malformed payload), end-to-end detection triggering, and metrics exposure. 7 unit tests for the LogRecord-to-JSON conversion.

LynxDB backend (PR #62)🔗

A new conversion backend for LynxDB, a Go-based log analytics engine with an SPL2-compatible query language. Translates Sigma detection rules into FROM <index> | search <predicates> queries with deferred | where clauses for features that require regex or CIDR evaluation.

Sigma feature LynxDB syntax
Field equality field=value, field="quoted value"
Wildcard (*) field=prefix*, field=*contains*
Wildcard (?) Deferred: \| where field =~ "regex"
Regex (\|re) Deferred: \| where field =~ "pattern"
CIDR (\|cidr) Deferred: \| where cidrmatch("cidr", field)
Case-sensitive (\|cased) field=CASE(value)
Boolean AND/OR/NOT Explicit parenthesization for LynxDB's non-standard precedence (NOT > OR > AND)
IN-list field IN (val1, val2, ...)
Keyword search Bare value (matches _raw)

Two output formats: default (FROM main | search ...) and minimal (search expression only, for API q parameters). Index selection from pipeline state, defaulting to main.

rsigma convert rules/suspicious_process.yml -t lynxdb
rsigma convert rules/ -t lynxdb -f minimal

Tests: 30+ unit tests and 9 golden test cases.

rsigma fields subcommand (PR #65)🔗

A new subcommand that extracts and lists every field name referenced by a set of Sigma rules. Useful for understanding field coverage, validating pipeline mappings, and auditing detection scope.

Field sources: detection item keys, correlation group_by and condition fields, correlation alias mapping values, filter detections, and rule fields: metadata. Each field is annotated with the source categories that reference it (detection, correlation, filter, metadata).

Flag Description
-r / --rules Path to a rule file or directory (required)
-p / --pipeline Pipeline YAML file(s) to apply; shows post-mapping field names
--no-filters Exclude fields contributed by filter rules
--json Output as JSON with summary stats and pipeline mapping details
rsigma fields -r rules/
rsigma fields -r rules/ -p pipelines/ecs.yml --json

Table output sends data to stdout and stats to stderr, enabling clean piping. 16 integration tests with insta inline snapshots.

Structured exit codes (PR #66)🔗

All subcommands now return categorized exit codes instead of a blanket exit(1) on any failure, enabling reliable CI/CD scripting with $?.

Exit code Constant Meaning
0 SUCCESS Operation completed successfully
1 FINDINGS Detections fired (eval) or lint findings above threshold (lint)
2 RULE_ERROR Rule syntax, parse, or compilation error
3 CONFIG_ERROR Pipeline, configuration, or invalid argument error

Two new flags control when a non-zero exit indicates "findings found":

  • eval --fail-on-detection: exit 1 when any detection or correlation fires.
  • lint --fail-level <error|warning|info>: configurable severity threshold; default error preserves backward compatibility.
rsigma eval -r rules/ events.json --fail-on-detection || exit 1
rsigma lint -r rules/ --fail-level warning

Per-rule Prometheus metrics (PR #63)🔗

Two new labeled IntCounterVec metrics alongside the existing aggregate counters enable per-rule alerting and dashboarding without parsing log output.

Metric Labels
rsigma_detection_matches_by_rule_total rule_title, level
rsigma_correlation_matches_by_rule_total rule_title, level, correlation_type
rate(rsigma_detection_matches_by_rule_total{rule_title="Okta Cross-Tenant Impersonation"}[5m]) > 100

Other changes🔗

  • Daemon hang fix: when the daemon-otlp feature was enabled with stdin or NATS input, the daemon could hang after the source completed because OTLP handler clones kept the event channel open. Fixed by signaling source completion via tokio::sync::Notify and draining the channel with select!.
  • CI hardening (PR #67 + follow-ups): added cargo-llvm-cov code coverage with native GitHub job summary report, zizmor workflow audit with pedantic persona and SARIF upload, concurrency groups on all workflows, and action pin fixes (dtolnay/rust-toolchain pinned to v1 tag, Swatinem/rust-cache pinned to dereferenced commit SHA). Codecov was initially added and then replaced with the native job summary to eliminate the external service dependency.
  • README rewrite: new Supported Features section, updated architecture diagrams, OTLP log ingestion documentation, and shield badges.
  • Test reliability: fixed a flaky macOS test where FSEvents file watcher backpressure filled the bounded reload channel, causing a 429 on the reload endpoint. The test now retries with backoff.

v0.8.1...v0.9.0

0.8.1 - 2026-04-29🔗

TL;DR RSigma v0.8.1 is a patch release for the PostgreSQL backend. Dotted Sigma field names (like securityContext.isProxy) now generate correct chained JSONB operators when using -O json_field=....

Nested JSONB field paths (#45)🔗

When json_field is set (e.g. -O json_field=data), the PostgreSQL backend now generates chained -> / ->> operators for dotted Sigma field names instead of treating the entire dotted string as a single flat key.

Before (v0.8.0):

SELECT * FROM okta_events WHERE data->>'securityContext.isProxy' = 'true'

After (v0.8.1):

SELECT * FROM okta_events WHERE data->'securityContext'->>'isProxy' = 'true'

Deeply nested paths work as expected:

Sigma field Generated SQL
eventType data->>'eventType' (unchanged)
securityContext.isProxy data->'securityContext'->>'isProxy'
actor.detail.sub.field data->'actor'->'detail'->'sub'->>'field'

All intermediate segments use -> (returns jsonb), and the final segment uses ->> (returns text). Flat field names without dots are unaffected. NULL propagation works correctly for existence checks: data->'nonexistent'->>'child' returns NULL, so IS NOT NULL behaves as expected on nested paths.

This is particularly important for Okta System Log rules from SigmaHQ, where fields like securityContext.isProxy and client.ipAddress reference nested JSON objects.

v0.8.0...v0.8.1

0.8.0 - 2026-04-28🔗

TL;DR RSigma v0.8.0 is the "rule conversion" release. A new rsigma-convert crate transforms Sigma rules into backend-native query strings through a pluggable Backend trait. The first production backend targets PostgreSQL/TimescaleDB, a backend unique to RSigma and inspired by pySigma-backend-sqlite and pySigma-backend-athena. The CLI gains convert, list-targets, and list-formats commands. Multi-arch Docker images are now published to GHCR on every release. Processing pipelines support one-to-many field name mapping, and filter rules reach full behavioral parity with pySigma.

Please test this (and RSigma in general) and provide feedback. Contributions are also very welcome.

rsigma-convert crate (#36)🔗

A new library crate for converting parsed Sigma rules into backend-native queries (SQL, SPL, KQL, Lucene, etc.):

  • Backend trait with ~30 methods covering condition dispatch, detection item conversion, field/value escaping, regex, CIDR, comparison operators, field existence, field references, keywords, IN-list optimization, deferred expressions, and query finalization.
  • TextQueryConfig with ~90 configuration fields mirroring pySigma's TextQueryBackend class variables: precedence, boolean operators, wildcards, string/field quoting, match expressions (startswith/endswith/contains + case-sensitive variants), regex/CIDR templates, compare ops, IN-list optimization, unbound values, deferred parts, and query envelope.
  • Condition tree walker that recursively converts ConditionExpr nodes into query strings with selector/quantifier support.
  • Orchestrator via convert_collection(), which applies pipelines, converts each rule, and collects results and errors.
  • Deferred expressions through the DeferredExpression trait and DeferredTextExpression for backends that need post-query appendages (e.g. Splunk | regex, | where).
  • Test backend (TextQueryTestBackend and MandatoryPipelineTestBackend) for backend-neutral foundation testing.

PostgreSQL/TimescaleDB backend (#37, #38, #43, #44)🔗

The first production backend, and one that has no equivalent in the pySigma ecosystem. It is inspired by pySigma-backend-sqlite and pySigma-backend-athena, targeting PostgreSQL natively and leveraging features that map cleanly to Sigma modifiers:

Sigma Modifier PostgreSQL SQL
contains ILIKE (case-insensitive)
startswith / endswith ILIKE
cased LIKE (case-sensitive)
re ~* (case-insensitive regex) or ~ (with cased)
cidr field::inet <<= 'value'::cidr
exists IS NOT NULL / IS NULL
keywords to_tsvector() @@ plainto_tsquery()

Five output formats:

Format Description
default Plain SELECT * FROM {table} WHERE ... queries
view CREATE OR REPLACE VIEW sigma_{id} AS SELECT ...
timescaledb Queries with time_bucket() for TimescaleDB optimization
continuous_aggregate CREATE MATERIALIZED VIEW ... WITH (timescaledb.continuous)
sliding_window Correlation queries using window functions for per-row sliding detection

Additional capabilities:

  • SELECT column selection (inspired by pySigma-backend-athena): when a Sigma rule specifies fields:, the backend emits SELECT field1, field2, ... instead of SELECT *. Supports field as alias syntax and passthrough of function calls.
  • CLI backend options: -O key=value flags are now wired through to the PostgreSQL backend. Recognized keys: table, schema, database, timestamp_field, json_field, case_sensitive_re.
  • Custom table/schema/database resolution at three levels: rule-level custom_attributes, pipeline set_state, and backend defaults.
  • Multi-table temporal correlations: when referenced detection rules target different tables (via per-logsource pipeline routing or custom attributes), the backend automatically generates a UNION ALL CTE. Single-table correlations use the simpler direct approach.
  • CTE-based correlation pre-filtering (inspired by pySigma-backend-athena): non-temporal correlations wrap referenced rules' queries in a WITH combined_events AS (q1 UNION ALL q2 ...) CTE, so aggregations only count events matching the detection logic rather than scanning the entire table.
  • Sliding window correlations (inspired by pySigma-backend-athena): the sliding_window output format uses SQL window functions (COUNT(*) OVER (PARTITION BY ... ORDER BY ... RANGE BETWEEN INTERVAL ... PRECEDING AND CURRENT ROW)) for event_count correlations. This produces a per-row sliding window that identifies every event crossing the threshold, complementing the default GROUP BY + HAVING approach for periodic polling.
  • OCSF processing pipelines: two included pipelines for single-table (ocsf_postgres.yml) and per-logsource multi-table routing (ocsf_postgres_multi_table.yml).
  • Reference TimescaleDB schema with hypertable setup, indexes (B-tree, GIN for full-text and JSONB), compression, retention policies, and an example continuous aggregate.
  • Correlation SQL generation using GROUP BY / HAVING for aggregation types (event_count, value_count, value_sum, value_avg, value_percentile, value_median) and CTEs with window functions for temporal correlation.

CLI: convert, list-targets, list-formats🔗

rsigma convert -r rules/ -t postgres
rsigma convert -r rules/ -t postgres -p pipelines/ocsf_postgres.yml -f view
rsigma convert -r rules/ -t postgres -p pipelines/ocsf_postgres_multi_table.yml
rsigma convert -r rules/ -t postgres -p pipelines/ocsf_postgres.yml -f continuous_aggregate
rsigma convert -r rules/ -t postgres -O table=security_logs -O schema=public -O timestamp_field=created_at
rsigma convert -r rules/ -t postgres -f sliding_window
rsigma list-targets
rsigma list-formats postgres

Options include -p / --pipeline (repeatable), -f / --format, -o / --output, --skip-unsupported, --without-pipeline, and -O / --option for backend-specific key=value pairs.

Multi-arch Docker image (#39)🔗

Multi-arch images (linux/amd64, linux/arm64) are published to GHCR on every release:

docker pull ghcr.io/timescale/rsigma:latest
docker run --rm ghcr.io/timescale/rsigma:latest --help

One-to-many field name mapping (#40, #41)🔗

Thanks to @fwosar, FieldNameMapping now supports mapping a single source field to multiple alternative field names. When more than one alternative is present, the matched detection item is replaced with an OR-conjunction (AnyOf) of items, one per alternative, preserving the rule's original AND structure across the rest of the items in the same selection via Cartesian expansion.

transformations:
  - id: multi_field_mapping
    type: field_name_mapping
    mapping:
      CommandLine:
        - process.command_line
        - process.args

The expansion is capped at 4,096 combinations per detection to prevent runaway Cartesian products in rules with many multi-mapped fields. For correlation rules, group_by fields are expanded to include all alternatives, while aliases mapping values and threshold field reject one-to-many mappings with an error since those positions are inherently scalar.

pySigma filter parity (#42)🔗

Filter rules now match pySigma semantics across parsing, application, and linting:

  • filter.rules accepts "any" (string) and omission, both meaning "apply to all rules". The new FilterRuleTarget enum (Any | Specific(Vec<String>)) replaces the old Vec<String>.
  • Filter condition expressions are rewritten with namespaced identifiers (__filter_0_selection) and applied as written, instead of hardcoding AND-NOT. Filters that exclude events must use not selection explicitly in their condition.
  • Logsource matching changed from symmetric compatibility to asymmetric containment: every field the filter specifies must be present and equal in the rule, but fields the filter omits are treated as wildcards.
  • FilterRule and CorrelationRule AST types now carry the full set of standard Sigma fields.

Pipeline and eval changes🔗

  • Pipeline finalizers: new pipeline/finalizers.rs module for post-pipeline processing hooks used by the conversion path.
  • QueryExpressionPlaceholders: this transformation now stores the expression template in pipeline state, enabling the conversion engine to apply query envelope templates.
  • apply_field_name_transform now returns Result<()>, propagating errors from one-to-many expansion overflow.

Breaking Changes🔗

Before (0.7.0) After (0.8.0)
FieldNameMapping { mapping: HashMap<String, String> } FieldNameMapping { mapping: HashMap<String, Vec<String>> }
CorrelationCondition::Threshold { predicates, field: Option<String> } CorrelationCondition::Threshold { predicates, field: Option<Vec<String>>, percentile: Option<u64> }
FilterRule { rules: Vec<String>, .. } FilterRule { rules: FilterRuleTarget, .. }
Filter conditions auto-negated (AND NOT filter_cond) Filter conditions applied as written (use not selection explicitly)

Contributors🔗

Thanks to @fwosar for the one-to-many field name mapping feature (#40).

v0.7.0...v0.8.0

0.7.0 - 2026-04-23🔗

TL;DR RSigma v0.7.0 is the "any log format" release. The evaluation engine now operates on a generic Event trait instead of raw JSON, a new rsigma-runtime library crate decouples the streaming pipeline from the CLI, and the daemon can ingest JSON, syslog (RFC 3164/5424), logfmt, CEF, and plain text, with auto-detection by default. Hand-rolled zero-dependency parsers for logfmt and CEF keep the dependency tree lean.

This release is inspired by sigma_engine, thanks to @thomaspatzke and Sigma HQ folks.

Generic Event trait (breaking)🔗

The rsigma-eval::Event struct has been replaced by an Event trait with three concrete implementations:

  • JsonEvent: wraps serde_json::Value (the previous behavior)
  • KvEvent: key-value map for structured formats (syslog, logfmt, CEF)
  • PlainEvent: raw text for keyword-only matching

An EventValue enum provides typed access to field values across all implementations. This is a breaking change: callers using Event::new(value) should switch to JsonEvent::borrow(&value) or JsonEvent::owned(value).

rsigma-runtime crate🔗

The streaming pipeline has been extracted from the CLI daemon into a reusable library crate:

  • RuntimeEngine: wraps Engine + CorrelationEngine with rule loading, hot-reload, and state management.
  • LogProcessor: batch processing pipeline with ArcSwap for atomic engine swap, pluggable MetricsHook, and EventFilter for JSON payload extraction (e.g. .records[]).
  • Input format adapters (input/ module): JSON, syslog, logfmt, CEF, plain text, and auto-detect.
  • I/O primitives: EventSource trait and Sink enum moved from the CLI.

Multi-format input (--input-format)🔗

The daemon and eval commands now accept --input-format and --syslog-tz:

rsigma daemon -r rules/
rsigma daemon -r rules/ --input-format syslog --syslog-tz +0530
rsigma eval -r rules/ --input-format logfmt < app.log
rsigma eval -r rules/ --input-format cef < arcsight.log

Auto-detect validates syslog parsing results (checks for facility/severity/hostname) before accepting and it won't misparse random text as syslog.

Zero-dependency parsers🔗

  • logfmt: hand-rolled parser supporting quoted values with escape sequences, bare keys, and mixed whitespace. No external dependencies.
  • CEF (Common Event Format): hand-rolled parser for the full ArcSight CEF spec including 7-field pipe-delimited header + key=value extensions with \=, \n, \\ escapes. Handles syslog-wrapped CEF via find_cef_start().

Both are feature-gated (logfmt, cef) and thoroughly tested with real-world log samples.

Examples and benchmarks🔗

Baseline results (Apple M4 Pro, 100 rules):

Format Throughput
Plain text 5.5-10.9 Melem/s
Syslog 1.26-1.40 Melem/s
JSON 955 Kelem/s-1.15 Melem/s
Auto-detect ~966 Kelem/s-1.09 Melem/s

Rule-count scaling is near-flat from 100 to 1,000 rules thanks to logsource index pruning.

Other changes🔗

  • Custom attributes (custom_attributes): propagate custom rule attributes through results, then unified across detection and correlation rules into a single custom_attributes field (breaking: custom_rule_attributes removed). Thanks to @fwosar (#26).
  • Lint --exclude: glob patterns to skip files during linting, plus detection of deprecated aggregation syntax.
  • Line feeds in conditions: fixed parsing of condition expressions containing line breaks. Thanks to @fwosar (#24).
  • Dependencies: notify 7 -> 8.2, rustls-webpki -> 0.103.13.
  • BENCHMARKS.md: documents all benchmark groups, baseline results, and the 5% regression threshold.

Breaking Changes🔗

Before (0.6.0) After (0.7.0)
use rsigma_eval::Event; (struct) use rsigma_eval::event::Event; (trait)
Event::new(value) JsonEvent::borrow(&value) or JsonEvent::owned(value)
Event::from_value(v) JsonEvent::borrow(&v)
result.custom_rule_attributes result.custom_attributes

Contributors🔗

Thanks to @fwosar for their contributions to this release (#24, #26).

v0.6.0...v0.7.0

0.6.0 - 2026-04-17🔗

TL;DR RSigma grew up. v0.6.0 makes the daemon production-ready for streaming detection: plug it into NATS JetStream or HTTP, fan out to multiple sinks, and let rayon + an inverted index chew through rules 2-3x faster. Stateful correlation still survives restarts via SQLite, stdin/stdout still works by default, and cargo audit is back to zero vulnerabilities.

This release resolves the "not meant for streaming logs" gap correctly identified in Detection Engineering Weekly #149 by Zack Allen and positions RSigma as a single-node streaming detection engine -- not just a CLI forensics tool. Three levels of work landed:

  1. Level 1: pluggable I/O adapters (NATS, HTTP, file, fan-out)
  2. Level 2: async pipeline hardening (backpressure, micro-batching, drain)
  3. Level 3: inverted index + feature-gated rayon parallel batch evaluation

Streaming I/O adapters (Level 1)🔗

The daemon now speaks NATS JetStream, HTTP, and files and not just stdin/stdout.

rsigma daemon -r rules/ --input http
rsigma daemon -r rules/ --input nats://localhost:4222/events.> --output nats://localhost:4222/detections
rsigma daemon -r rules/ --output file:///var/log/detections.ndjson
rsigma daemon -r rules/ --output stdout --output file:///tmp/detections.ndjson
  • EventSource trait + Sink enum: pluggable adapters with enum dispatch; async-friendly Sink::FanOut(Vec<Sink>) for multi-sink output.
  • --input/--output URL schemes: stdin://, http://, nats://, file://, stdout://; multiple --output flags clone ProcessResult per sink via bounded mpsc channels.
  • daemon-nats feature flag: gates async-nats; durable JetStream consumer with ACK, publisher sink.

Async pipeline hardening (Level 2)🔗

  • Fully async stdin via tokio::io::AsyncBufReadExt (no more spawn_blocking).
  • Configurable back-pressure: --buffer-size (default 10,000) sets bounded mpsc capacity for both source-to-engine and engine-to-sink queues.
  • Micro-batched evaluation: --batch-size (default 1); engine collects up to N events per mutex acquisition via try_recv().
  • Graceful drain on shutdown: --drain-timeout (default 5s) lets in-flight events finish before state save; natural EOF drains without timeout.
  • 5 new Prometheus metrics: rsigma_input_queue_depth, rsigma_output_queue_depth, rsigma_back_pressure_events_total, rsigma_pipeline_latency_seconds, rsigma_batch_size.

Performance: inverted index + parallel batch evaluation (Level 3)🔗

  • Inverted index: RuleIndex maps (field, exact_value) to rule indices at load time. Engine::evaluate() queries candidates instead of scanning all rules. Rules without exact-match items are marked unindexable and always evaluated (no false negatives).
  • Feature-gated rayon: new parallel feature on rsigma-eval enables Engine::evaluate_batch() and CorrelationEngine::process_batch(). Parallel detection + sequential correlation via a borrow split.
  • Benchmark results (5,000 rules, synthetic events):
  • Detection evaluation: 2.4-2.7x speedup from indexing alone.
  • Correlation throughput: ~1.7x improvement (indexed + sequential).
  • Batch evaluation scales with core count.

New public APIs (rsigma-eval)🔗

  • Engine::evaluate_batch(&self, events: &[&Event]) -> Vec<Vec<MatchResult>>
  • CorrelationEngine::evaluate(&self, event: &Event) -> Vec<MatchResult>
  • CorrelationEngine::process_with_detections(&mut self, event, detections, timestamp_secs) -> ProcessResult
  • CorrelationEngine::process_batch(&mut self, events: &[&Event]) -> Vec<ProcessResult>

Pipeline parity🔗

  • Named condition IDs supported in rule_cond_expression (not just numeric indices).
  • Correlation rules now apply processing pipelines consistently with detection rules.

Dependencies and security🔗

  • async-nats 0.46 to 0.47 (drops pinned vulnerable rustls-webpki 0.102.8, rustls-pemfile 2.2.0, rand 0.8.5)
  • rustls-webpki to 0.103.12 (RUSTSEC-2026-0049/-0098/-0099)
  • rand to 0.9.4 (RUSTSEC-2026-0097)
  • lodash override to 4.18.x in VS Code extension (devDependency-only)
  • cargo audit: 0 vulnerabilities

v0.5.0...v0.6.0

0.5.0 - 2026-02-26🔗

Daemon mode (rsigma daemon)🔗

rsigma can now run as a long-running service for real-time event processing, with hot-reload, health checks, metrics, and a REST API.

rsigma daemon -r rules/ -p ecs.yml --api-addr 127.0.0.1:8080
  • Hot-reload: file watcher, SIGHUP, and /api/v1/reload endpoint. Correlation state is preserved across reloads.
  • Health endpoints: /healthz, /readyz
  • Prometheus metrics: events processed, detection/correlation matches, rules loaded, uptime, state entries
  • REST API: /api/v1/status, /api/v1/rules, /api/v1/reload
  • Structured logging: JSON via tracing with RUST_LOG control

SQLite state persistence (--state-db)🔗

Correlation state (windows, suppression timers, event buffers) now survives daemon restarts.

rsigma daemon -r rules/ -p ecs.yml --state-db ./rsigma-state.db --state-save-interval 10
  • Periodic snapshots (configurable via --state-save-interval, default 30s)
  • Graceful shutdown save
  • Schema-versioned snapshots for forward compatibility
  • Base64-encoded compressed event buffers for efficient storage
  • State preserved across hot-reloads (export before engine swap, re-import after)

CI🔗

  • All workflows now use --all-features to cover daemon-gated code

Dependencies🔗

  • Removed protobuf transitive dependency (disabled prometheus default features) -- resolves RUSTSEC-2024-0437

v0.4.0...v0.5.0

0.4.0 - 2026-02-23🔗

Bug fixes🔗

  • Filter name collision -- Multiple filters sharing detection names (e.g. both using selection) no longer overwrite each other. Filter detections are now namespaced with a counter to prevent key collisions.
  • CVE-2026-26996 -- Upgraded minimatch to 10.2.1 in the VS Code extension.

Validation improvements🔗

  • UnknownDetection at compile time -- Condition expressions referencing non-existent detections now fail eagerly during compile_rule() instead of silently at eval time.
  • UnknownRuleRef at load time -- Correlation rule_refs are validated to resolve to known rules or correlations when calling add_collection().

Dependency upgrades🔗

  • yamlpatch 0.11 to 0.12, yamlpath 0.33 to 0.34 (Unicode-aware patching, empty-route RewriteFragment fix).
  • jsonschema 0.29 to 0.42 (13 minor versions of improvements).
  • tower-lsp 0.20 to tower-lsp-server 0.23 (actively maintained community fork; native async traits).
  • 49 transitive crate updates via cargo update.

Test coverage🔗

  • ~1,300 lines of new tests: end-to-end integration, correlation edge cases, parser/eval error paths, and pipeline error handling.

Breaking changes🔗

  • Removed EvalError::TimestampParse variant (unused).

v0.3.0...v0.4.0

0.3.0 - 2026-02-19🔗

Auto-fix for Sigma lint rules🔗

This release adds machine-applicable fix suggestions to the linter, exposed through both the CLI and the LSP server.

  • rsigma lint --fix -- Apply safe fixes in-place. Uses format-preserving YAML editing (yamlpath/yamlpatch) so comments and formatting are retained.
  • LSP code actions -- Quick-fix lightbulb in editors for all fixable lint warnings. Fixes are converted to TextEdits and offered when the cursor overlaps the warning range.
  • Fix infrastructure -- Fix, FixDisposition (Safe/Unsafe), and FixPatch (ReplaceValue, ReplaceKey, Remove) types in rsigma-parser. 13 lint rules carry safe fix suggestions.

Improvements🔗

  • Improved parser error reporting with better span information.
  • Expanded modifier validation and test coverage.

Fixable lint rules🔗

invalid_status, invalid_level, non_lowercase_key, logsource_value_not_lowercase, unknown_key, duplicate_tags, duplicate_references, duplicate_fields, single_value_all_modifier, all_with_re, wildcard_only_value, filter_has_level, filter_has_status

v0.2.0...v0.3.0

0.2.0 - 2026-02-17🔗

Linter, LSP, Processing Pipelines, and Correlation Engine🔗

First release of rsigma -- a Sigma detection toolkit in Rust. Ships a parser, evaluation engine, 65-rule linter, LSP server, processing pipelines, correlation engine, and cross-platform CLI.

New features🔗

  • Parser (rsigma-parser) -- Sigma YAML to strongly-typed AST via PEG grammar; 30 modifiers; multi-document YAML support.
  • Evaluation engine (rsigma-eval) -- Compile-then-evaluate architecture for Sigma rules against JSON log events.
  • Linter -- 65 built-in lint rules from the Sigma spec v2.1.0 with Error/Warning/Info/Hint severity, per-rule suppression (rsigma-suppress), and colored terminal output.
  • LSP server (rsigma-lsp) -- Diagnostics, completions, hover, and document symbols; packaged as a VS Code extension with esbuild bundling.
  • Processing pipelines -- All 26 pySigma transformation types for full pipeline parity (field mapping, value transforms, logsource rewriting, drop rules).
  • Correlation engine -- All 7 Sigma correlation types plus repeat, percentile, and range conditions; configurable timestamp fallback; cycle detection; chain depth warnings; compressed event storage for include_event mode.
  • CLI -- parse, validate, eval, lint subcommands; @file syntax for --event; --jq/--jsonpath event filters; alert suppression; action-on-fire; generate flag; NDJSON streaming.
  • Binary release workflow for cross-platform builds (Linux, macOS, Windows).
  • Trusted publishing workflow for crates.io.
  • CI: tests on Linux/macOS/Windows, Sigma corpus regression job, cargo-audit security scanning.

Fixes🔗

  • Hard cap on correlation state when time-based eviction is insufficient.
  • Empty AllOf/AnyOf detections rejected at compile time.
  • |re modifier is case-sensitive by default per Sigma spec.
  • windash modifier includes all five Sigma spec characters.
  • Event::get_field traverses arrays in dot-notation paths.
  • Unicode-aware case folding for case-insensitive matching.
  • Timestamp clamping in process_event_at to prevent overflow.
  • Memory leak in linter.

Performance🔗

  • Pre-compiled regex patterns in pipeline conditions.
  • Eliminated hot-path cloning in correlation engine.
  • Eliminated Vec and String allocations in keyword matching.

v0.2.0

0.1.0 - 2026-02-17🔗

Initial crates.io publish. Reserved the rsigma crate name with a minimal CLI binary (parser + evaluator only, no linter/LSP/pipelines/correlation). Superseded the same day by v0.2.0, which is the first feature-complete release.