* feat(pdg): add CDG + POST_DOMINATE edge types (M5 #2085) * feat(pdg): post-dominator tree on reverse CFG (M5 #2085) * feat(pdg): Ferrante control-dependence over the post-dom tree (M5 #2085) * feat(pdg): emitFileCdg + optional POST_DOMINATE debug edges (M5 #2085) * feat(pdg): wire CDG emission in-phase + pdgModeMismatch CDG-cap stamp (M5 #2085) * test(pdg): CDG snapshot + end-to-end pipeline answerability (M5 #2085) * fix(review): apply autofix feedback (M5 #2085) * fix(pdg): label CDG edges by controller arm sense, not edge kind (#2188 F1/F2/F4) Tri-review (with Codex as the independent engine) found the CDG 'T'/'F' label was wrong for the commonest control flow: the M1 TS visitor wires a condition's fall-through FALSE arm as `seq`/`loop-back`, but `branchSense` mapped both to 'T', so guard clauses, if-no-else, and loop `break` got 'T' instead of 'F' (F1, P1). The structural CDG edges were correct; only the label — the AC3 "under what condition does X run?" answer — was wrong. - F1: replace edge-kind `branchSense` with controller-arm-sense `labelFor`. An ambiguous fall-through edge (seq/loop-back) takes the COMPLEMENT of its source block's explicit cond-true/cond-false sibling arm. This correctly handles do/while (loop-back = TRUE arm) and inner-if-in-loop (loop-back = FALSE arm) — the ambiguity a kind→label table cannot resolve. Adds real-parser regression tests (the hand-built tests used a fictional cond-false edge and missed it). - F2: correct the false "sound over-approximation that never drops a real dependence" claim in post-dominators.ts — exit-unreachable regions both drop and invent control dependences (latent for the current TS visitor, which keeps EXIT reverse-reachable). Reframe the exit-less-loop test to characterize, not bless, the degenerate behavior. - F4: make the AC2 property-test reference compute post-dominance INDEPENDENTLY (node-removal reachability, no shared code with post-dominators.ts), so a post-dom direction bug can no longer pass both the impl and the reference. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fix(ci): root-prettier format + run-analyze pdg stamp gains maxCdgEdgesPerFunction (#2085) Two deterministic CI failures from the M5 CDG work: - quality/format: basicblock-roundtrip.test.ts failed CI's root `prettier --check .` (the pre-commit hook uses the gitnexus-local prettier config, which differs); reformatted with the root config. - tests/ubuntu/coverage: run-analyze.test.ts pinned the resolved RepoMeta.pdg shape (DEFAULTS) and the all-zero cap override without the new maxCdgEdgesPerFunction key (default 5000); added it so resolvePdgConfig toEqual and pdgModeMismatch(DEFAULTS) pass. (The stale-test sweep missed this file in PR #2188 — same trap M2 hit.) Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * feat(mcp): add pdg_query tool definition (controls/flows modes) [M6 #2086] * feat(mcp): pdg_query backend — controls (CDG) + flows (REACHING_DEF) + e2e test [M6 #2086] * feat(mcp): document PDG edges + pdg_query (schema, cypher, skill, --pdg-gated ai-context) [M6 #2086] * fix(mcp): correct pdg_query symbol-anchor lower bound + harden inputs [PR #2188 review] Tri-review (Codex + adversarial + correctness lanes) of the M6 pdg_query surface found the symbol-anchor window over-includes a neighbor function's block. The upper bound was widened to the 1-based BasicBlock basis (symEnd+1) but the lower bound was left 0-based, so a block on the line directly above the target function leaked into the result. Shift both bounds +1 ([symStart+1, symEnd+1]) so the window is the function's true block span. Also from the same review: - pdg_query no longer throws on a no-arguments MCP call: the dispatch passes raw `params`, so default it to {} → a clean mode-validation error instead of a TypeError. (`explain` shares this latent pattern — pre-existing follow-up.) - tools.ts: the controls-mode description no longer hard-codes the 'F' branch sense for guards — `if (!ok) return;` rides the predicate's 'T' arm; the guard:true flag is label-agnostic (regex on the dependent block text). Tests: a hand-seeded adjacency regression (verified failing without the lower-bound +1) + a no-arguments validation test. Skill doc updated to document the two-sided [symStart+1, symEnd+1] window. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fix(mcp): drop always-true anchor conditional in pdg_query [CodeQL #2188] CodeQL alert 756 flagged `...(anchor ? { anchor } : {})` in _pdgQueryImpl as a useless conditional: `anchor` is unconditionally assigned in both the file-path and symbol branches before the return (the not-found/ambiguous/no-layer paths return earlier), so it is always truthy. Drop `| undefined` from the declaration (TypeScript definite-assignment holds across both branches) and emit `anchor` directly. No runtime change — the `anchor` field was already present on every result. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * test(cli): add hasPdg to the noStats bridge expectation [#2188] The M6 work threaded `hasPdg: options.pdg === true` into the AIContextOptions passed to generateAIContextFiles on the --skills regeneration path, but this test's strict .toEqual expectation predated it (4 keys vs 3 → CI failure). Add `hasPdg: false` (the value on this non---pdg path). The assertion stays strict; the #1477 noStats bridging it guards is unchanged. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * refactor(cli): collapse generateGitNexusContent params to an options bag [#2188] The function had grown to 9 positional params; reaching `hasPdg` meant passing six `undefined`s (the M6 review's maintainability flag). Collapse params 3-9 (generatedSkills, groupNames, noStats, skipSkills, runnerPath, defaultBranch, hasPdg) into a `GitNexusContentOptions` object with the defaults moved to destructuring. The body is unchanged (same local names); the single production caller and the test calls become self-documenting named fields. Pure refactor — generated AGENTS.md/CLAUDE.md content is byte-identical. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fix(cfg): skip CDG for exit-unreachable CFGs (unsound post-dominance) [#2188] M5 review P2: computePostDominators roots only at cfg.exitIndex and nothing enforced that EXIT is reachable from every block. For an entry-reachable region that cannot reach EXIT (a non-terminating loop, or a multi-terminal CFG a future visitor might emit) the EXIT-rooted reverse walk degenerates — it both drops real control dependences and invents spurious ones. Add a pure precondition predicate `isExitReachableFromAllBlocks` (co-located with the algorithm it guards) and gate it in emitFileCdg: a CFG that violates it is skipped for CDG (counted as skippedUnsoundFunctions + one onWarn), while its CFG and REACHING_DEF projections — which do not depend on post-dominance — are kept. A CDG-specific gate, not a widening of isEmitSafeCfg, so the blast radius is exactly the unsound CDG. The current TS visitor always satisfies the precondition (every loop gets a structural header→loopExit edge), so CDG output for real fixtures is unchanged. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fix(cfg): bound computeControlDependence materialization (heap parity) [#2188] M5 review P2: unlike computeReachingDefs (maxFacts) and the emit-side edge cap, computeControlDependence materialized the full deduped seen/out before emitFileCdg's per-function cap could trim it — O(edges × post-dom depth) heap for a deeply nested function. Add a `maxEdges` ceiling (default 0 = unbounded) returning {edges, truncated}, mirroring computeReachingDefs's {facts, truncated}. The ceiling is checked before pushing a new unique edge, so `truncated` means a genuine overflow (not merely "reached cap"). emitFileCdg passes a FIXED materialization ceiling (8× the default edge cap) — deliberately NOT derived from the runtime edge cap, because CDG's materialization IS the deduped-edge quantity the cap reports on (deriving it would pre-truncate that set and lose the exact dropped count). A ceiling hit is surfaced via onWarn + the truncated flag — never silent. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * refactor(mcp): share resolveBlockAnchor; fix explain's anchor off-by-one [#2188] M6 review P2 (duplication) + the flagged pre-existing _explainImpl correctness follow-up. _pdgQueryImpl and _explainImpl each carried a near-identical symbol↔block anchor resolver that had DRIFTED: pdg_query used the corrected [symStart+1, symEnd+1] window (BasicBlock startLine is 1-based, the symbol span 0-based) while _explainImpl still used [symStart, symEnd] — dropping a taint source on the function's final line AND leaking a neighbor's block on the line directly above. Extract one `resolveBlockAnchor` helper, used by both, that applies the correct window and a single (bare) clause convention (callers compose their own WHERE). This removes ~50 duplicated lines and fixes explain's anchor in one place. A hand-seeded characterization test (taint-explain Block 4) pins both bounds — verified to FAIL on the pre-fix window (it returned the line-10 neighbor instead of the line-15 final-line source). Existing taint-explain + pdg-query suites are unchanged (their fixtures have interior sources/sinks). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * fix(mcp): pdg_query reports "status unknown" when the layer can't be confirmed [#2188] M6 review P3 (Codex): when meta is UNREADABLE and the bounded global existence probe returns zero rows of the edge type, _pdgQueryImpl asserted "no PDG layer" — but a genuinely edge-free layer (all-linear functions) is indistinguishable from a missing one via that probe. Soften only that fallback path to an inconclusive "PDG layer status unknown — was this repo indexed with --pdg?" note. The meta-stamped path (stamp present, cap absent ⇒ layer truly missing) keeps the definitive "no PDG layer" wording. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * test(mcp): cover pdg_query ambiguous / pagination / Windows-path gaps [#2188] M6 review test-gap follow-ups, all hand-seeded with controlled data: - ambiguous symbol name → status:'ambiguous' + ranked candidates shape (uid/name/filePath/score), never a silent guess; - total/truncated page boundary in both directions (limit below the match count sets truncated with the full total; limit above it omits truncated); - a Windows-style filePath containing ':' resolves and fnLineOf decodes the function-line segment correctly (split-from-right past the drive letter). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * docs(skills): ship gitnexus-pdg-query skill mirrors + add pdg_query to the guide [#2086] M6 bundled pdg_query into this PR, but the skill shipped only in the canonical gitnexus/skills/ root. Mirror it (byte-identical) to the two hand-maintained roots the sibling taint skill uses — .claude/skills/gitnexus/ and the plugin — so Claude Code + plugin users get it too. Also extend the gitnexus-guide tool reference (all 3 copies, now byte-identical): add a `pdg_query` row + a "Control & data dependence" section mirroring the taint/`explain` section, and reconcile the pre-existing drift where only the .claude copy carried the `check` tool row (a real registered tool) — all three now list it. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * docs(architecture): refresh CFG/PDG section for the full M1–M6 stack [#2086] The PR body had deferred the "ARCHITECTURE docs refresh" to #2086; now that M6 ships here, do it: - MCP tools table gains `explain` and `pdg_query` (were absent). - "Optional CFG/PDG emission" was M1-only; rewrite to cover the whole opt-in stack — M1 CFG, M2 REACHING_DEF, M3/M4 taint, M5 CDG (Ferrante over CHK post-dominators, with the exit-unreachable skip), M6 read surface (pdg_query + explain, anchored + LIMIT-bounded, shared resolveBlockAnchor) — and note the no-Function→BasicBlock-edge join. - LadybugDB schema notes the `--pdg` additions: the `BasicBlock` node table and the CFG/REACHING_DEF/CDG/TAINTED/SANITIZES/TAINT_PATH relation types, kept out of the default VALID_RELATION_TYPES / web schema. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
31 KiB
Architecture — GitNexus
Monorepo: CLI/MCP (gitnexus/) + browser UI (gitnexus-web/).
Repository layout
| Path | Role |
|---|---|
gitnexus/ |
npm package gitnexus: CLI, MCP server (stdio), HTTP API, ingestion pipeline, LadybugDB graph, embeddings. |
gitnexus-web/ |
Vite + React thin client: graph explorer + AI chat. All queries via gitnexus serve HTTP API. |
gitnexus-shared/ |
Shared TypeScript types and constants (consumed by CLI and Web). |
.claude/, gitnexus-claude-plugin/, gitnexus-cursor-integration/ |
Agent skills and plugin metadata. |
eval/ |
Evaluation harnesses for benchmarking tool usage. |
.github/ |
CI workflows + composite actions (setup-gitnexus/, setup-gitnexus-web/). |
End-to-end flow: index → graph → tools
-
Ingestion —
analyze.ts→runFullAnalysis(run-analyze.ts) →runPipelineFromRepo(pipeline.ts). DAG of 14 phases builds aKnowledgeGraphin memory, then loads into LadybugDB under.gitnexus/. Repo registered in~/.gitnexus/registry.jsonfor MCP discovery. -
Persistence —
repo-manager.ts(paths, registry, KuzuDB cleanup).lbug-adapter.ts(graph load, queries, embedding batches). -
Query layer — three interfaces to the same backend:
- MCP (stdio):
mcp.ts→LocalBackend→ tools (tools.ts) + resources (resources.ts) - HTTP bridge:
serve.ts→ Express (api.ts,mcp-http.ts) for web UI - CLI direct:
gitnexus query|context|impact|cypherintool.ts
- MCP (stdio):
-
Staleness —
staleness.tscompares indexedlastCommittoHEAD, surfaces hints.
MCP tools
| Tool | Purpose |
|---|---|
list_repos |
Discover indexed repos |
query |
Hybrid BM25 + vector search over the graph |
cypher |
Ad hoc Cypher against the schema |
context |
Callers, callees, processes for one symbol |
impact |
Blast radius (upstream/downstream) with risk summary |
detect_changes |
Map git diffs to affected symbols and processes |
rename |
Graph-assisted multi-file rename with dry_run preview |
api_impact |
Pre-change impact report for an API route handler |
route_map |
API route → handler → consumer mappings |
tool_map |
MCP/RPC tool definitions and handlers |
shape_check |
Response shape vs consumer property access mismatches |
explain |
Persisted taint findings (source→sink data flows) — needs analyze --pdg |
pdg_query |
Control/data dependence — CDG (mode: controls) / REACHING_DEF (mode: flows) — needs analyze --pdg |
group_list |
List repo groups or details for one group |
group_sync |
Rebuild group Contract Registry (contracts.json) and bridge graph |
query, context, and impact are group-aware: pass repo: "@<groupName>" (or "@<groupName>/<memberPath>" to scope to one member) plus optional service: "<monorepo/path>". Group-mode query merges per-repo results via Reciprocal Rank Fusion; group-mode impact runs the local walk in the chosen member and fans out across boundaries via the Contract Bridge (gitnexus/src/core/group/cross-impact.ts). The previously-planned group_query, group_context, group_impact, group_contracts, group_status MCP tools are intentionally not introduced — group-level state is exposed via resources instead:
| Resource URI | Purpose |
|---|---|
gitnexus://group/{name}/contracts |
Contract Registry (provider/consumer rows + cross-links) |
gitnexus://group/{name}/status |
Per-member index + Contract Registry staleness |
Where to change what
| Concern | Start in |
|---|---|
| CLI commands/flags | src/cli/ (index.ts, per-command modules) |
| Parsing/graph construction | src/core/ingestion/pipeline-phases/ + pipeline.ts |
| Graph schema/DB | src/core/lbug/ (schema.ts, lbug-adapter.ts) |
| MCP tools/resources | src/mcp/server.ts, tools.ts, resources.ts |
Cross-repo groups (sync, contracts, @<group> routing) |
src/core/group/ (service.ts, cross-impact.ts, sync.ts, bridge-db.ts) |
| Search ranking | src/core/search/ (BM25, hybrid fusion) |
| Embeddings | src/core/embeddings/ + src/core/run-analyze.ts |
| Wiki generation | src/core/wiki/ |
| Language support | src/core/ingestion/languages/ + tree-sitter-queries.ts + gitnexus-shared/src/languages.ts |
| Import resolution | src/core/ingestion/import-processor.ts + import-resolvers/configs/ + model/resolution-context.ts |
| Call resolution/inheritance/MRO | src/core/ingestion/scope-resolution/ (pipeline, passes, graph-bridge) |
| Type extraction | src/core/ingestion/type-extractors/ |
| Worker pool | src/core/ingestion/workers/ |
| Web UI | gitnexus-web/src/ |
| CI | .github/workflows/*.yml, .github/actions/ |
Paths above are relative to
gitnexus/unless they start withgitnexus-web/or.github/.
Pipeline Phase DAG
14 phases defined in gitnexus/src/core/ingestion/pipeline-phases/, each with explicit deps and typed output.
scan → structure → [markdown, cobol] → parse → [routes, tools, orm]
→ crossFile → scopeResolution → pruneLocalSymbols → mro → communities → processes
| Phase | File | Deps | Output |
|---|---|---|---|
scan |
scan.ts |
(root) | File paths + sizes |
structure |
structure.ts |
scan |
File/Folder nodes, CONTAINS edges, allPathSet |
markdown |
markdown.ts |
structure |
Section nodes, cross-link edges from .md/.mdx |
cobol |
cobol.ts |
structure |
COBOL program/paragraph/section nodes (regex, no tree-sitter) |
parse |
parse.ts + parse-impl.ts |
structure, markdown, cobol |
Symbol nodes, IMPORTS/CALLS/EXTENDS edges, extracted routes/tools/ORM queries |
routes |
routes.ts |
parse |
Route nodes + HANDLES_ROUTE edges (Next.js, Expo, PHP, decorators) |
tools |
tools.ts |
parse |
Tool nodes + HANDLES_TOOL edges |
orm |
orm.ts |
parse |
QUERIES edges (Prisma, Supabase) |
crossFile |
cross-file.ts + cross-file-impl.ts |
parse, routes, tools, orm |
Cross-file type propagation in topological import order |
scopeResolution |
scope-resolution/pipeline/phase.ts |
parse, crossFile, structure |
Binding/reference + inheritance edges; disposes BindingAccumulator |
pruneLocalSymbols |
prune-local-symbols.ts |
scopeResolution |
Drops inert block-local Const/Variable/Static nodes (only a File→DEFINES edge) post-resolution |
mro |
mro.ts |
crossFile, scopeResolution, pruneLocalSymbols, structure |
METHOD_OVERRIDES + METHOD_IMPLEMENTS edges |
communities |
communities.ts |
mro, pruneLocalSymbols, structure |
Community nodes + MEMBER_OF edges (Leiden algorithm) |
processes |
processes.ts |
communities, routes, tools, pruneLocalSymbols, structure |
Process nodes + STEP_IN_PROCESS edges |
Non-phase files in the same directory: parse-impl.ts, cross-file-impl.ts (implementation), wildcard-synthesis.ts (whole-module import expansion), types.ts, runner.ts, index.ts.
DAG runner
runner.ts — static phase graph, no plugins, compile-time type safety.
-
Validation — Kahn's topological sort. Rejects on: duplicate names, missing deps, cycles (DFS traces the concrete cycle path, e.g.,
A -> B -> C -> A, plus count of transitively blocked dependents). -
Execution — sequential in topological order. Each phase receives:
ctx: PipelineContext— shared mutableKnowledgeGraph,repoPath, progress callback, optionsdeps: ReadonlyMap<string, PhaseResult>— declared deps only (runner filters the results map to prevent hidden coupling)
-
Error handling — wraps phase errors with the phase name, emits terminal
errorprogress event, swallows progress handler errors to preserve the original cause. -
Timing — per-phase
durationMsinPhaseResult, dev-mode console logging.
Design patterns:
- Single graph accumulator — all phases mutate the same
KnowledgeGraphinctx; the graph is the primary output. - Typed phase access —
getPhaseOutput<T>(deps, 'name')for type-safe upstream results. - Binding accumulator lifecycle — created in
parse, disposed bycrossFile(infinally). No other phase should take ownership. - Skippable phases —
skipGraphPhasesomits MRO/communities/processes (faster tests);pruneLocalSymbolsstill runs (it is graph cleanup, not analysis).skipWorkersis no longer a sequential escape hatch — it (like--workers 0/GITNEXUS_WORKER_POOL_SIZE=0) is rejected with an actionable error, since the worker pool is the sole parse path (§ Chunked parse-and-resolve). - Local-symbol pruning —
pruneLocalSymbolsremoves inert block-local value symbols after scope resolution has consumed them. Opt out per-call withPipelineOptions.keepLocalValueSymbolsor globally with theGITNEXUS_KEEP_LOCAL_VALUE_SYMBOLSenv var.
How to add a new phase
- Create
pipeline-phases/my-phase.tswith aPipelinePhase<MyOutput>(name, deps, execute) - Export from
pipeline-phases/index.ts - Add to
buildPhaseList()inpipeline.ts
import type { PipelinePhase, PhaseResult } from './types.js';
import { getPhaseOutput } from './types.js';
import type { ParseOutput } from './parse.js';
export interface MyPhaseOutput { /* ... */ }
export const myPhase: PipelinePhase<MyPhaseOutput> = {
name: 'myPhase',
deps: ['parse'],
async execute(ctx, deps) {
const { allPaths } = getPhaseOutput<ParseOutput>(deps, 'parse');
// ... write to ctx.graph ...
return { /* typed output */ };
},
};
Semantic model
SemanticModel (gitnexus/src/core/ingestion/model/semantic-model.ts) is the authoritative store for every symbol-indexed lookup (by nodeId, simpleName, qualifiedName, or filePath). The scope-resolution pipeline reads from here: findOwnedMember, pickOverload, and findExportedDefByName all consult model.methods / model.fields / model.symbols.
ParsedFile (gitnexus-shared/src/scope-resolution/parsed-file.ts) is the single per-file artifact the scope-resolution pipeline consumes. Scope-resolution passes MUST NOT build a parallel parse representation. If a per-language hook needs AST-level facts that ParsedFile doesn't expose, it should reuse the orchestrator's treeCache (RunScopeResolutionInput.treeCache) rather than re-invoking parser.parse(...) on its own — the C# populateNamespaceSiblings hook is the reference implementation of this pattern.
The scope-resolution pipeline additionally carries WorkspaceResolutionIndex for Scope-valued lookups (classScopeByDefId, moduleScopeByFile) that SemanticModel structurally cannot hold. No symbol-indexed duplicates exist outside SemanticModel.
Write / read phase contract. The model is mutable during three ordered phases and read-only afterward:
Phase 1: parse ──► symbolTable.add fans into types/methods/fields
Phase 2: scope-resolution ──► reconcileOwnership() registers corrected ownerIds
Phase 3: finalize ──► model.attachScopeIndexes(bundle) — one-shot freeze
─────────────────────────── phase boundary ───────────────────────────
Read phase: all resolution passes + MCP + HTTP + embeddings see
SemanticModel (read-only handle); writes are type-errors.
runScopeResolution narrows MutableSemanticModel → SemanticModel at the phase boundary so downstream passes physically cannot mutate the model even accidentally.
Reconciliation pass. reconcileOwnership (scope-resolution/pipeline/reconcile-ownership.ts) is a shim for languages whose parse-time extractor doesn't resolve enclosingClassId at parse time (Python class-body methods are the canonical case). It walks parsed.localDefs[i].ownerId after populateOwners and registers any missed methods/fields into the model. Idempotent — safe to re-run, safe alongside languages whose extractor already carries ownerId (C#).
The architectural end state is for every language's parse-time extractor to emit the correct ownerId directly, making reconciliation a no-op (tracked as a follow-up refactor). The dev-mode validator validateOwnershipParity surfaces any drift via onWarn under NODE_ENV !== 'production' && VALIDATE_SEMANTIC_MODEL !== '0'.
References: semantic-model.ts file-head (full write/read contract); contract/scope-resolver.ts Contract Invariant I9 (scope-resolution-side rule).
Scope-Resolution Pipeline (RFC #909 Ring 3)
Language-agnostic scope-resolution resolver. This is the resolution path for every language — it owns CALLS/ACCESSES/USES emission and inheritance edges. Adding a language is one interface implementation (ScopeResolver) plus one registration in the SCOPE_RESOLVERS map — no changes to shared code, no new pipeline phase. (RING4-1 #942 removed the legacy call-resolution DAG and the per-language MIGRATED_LANGUAGES flag, so SCOPE_RESOLVERS registration is all that's needed.)
Pipeline stages
ParsedFile[] (extractParsedFile per file)
│ finalizeScopeModel (+ provider hooks)
▼
ScopeResolutionIndexes
│ resolveReferenceSites (via MethodRegistry.lookup)
▼
ReferenceIndex
│ emitReceiverBoundCalls ── FIRST
│ emitFreeCallFallback ── THEN
│ emitReferencesViaLookup ── LAST (uses handledSites)
│ emitImportEdges
▼
KnowledgeGraph (IMPORTS / CALLS / ACCESSES / INHERITS / USES)
Orchestrator: runScopeResolution(input, provider) in scope-resolution/pipeline/run.ts.
Pipeline phase: scopeResolutionPhase in scope-resolution/pipeline/phase.ts — iterates the registered SCOPE_RESOLVERS over the worker-serialized ParsedFiles. (Per-language emitScopeCaptures hooks may reuse a cached Tree via the orchestrator's treeCache, but in worker-pool runs that cache is empty — Trees can't cross MessageChannels — so they consume the pre-extracted ParsedFile instead; § Performance notes.)
Optional CFG/PDG emission (--pdg, #2081–#2086)
On a --pdg run the parse worker builds a per-function control-flow graph from the tree-sitter AST (LanguageProvider.cfgVisitor; TypeScript/JavaScript today) and serializes it onto ParsedFile.cfgSideChannel as plain data. Scope-resolution then emits the program-dependence layers from that side-channel inside Phase 4 of runScopeResolution, while the disk-backed ParsedFile store is still live — the only window where the worker-built CFGs are loaded (the store is cleared right after the phase returns). A standalone post-mro phase would read an empty store, so the emit deliberately lives in-phase, mirroring the applyCaptureSideChannel pattern. The opt-in is off by default (graph byte-identical), folded into the parse-cache key (a pdg-off warm cache is never reused on a --pdg run), and each layer is bounded by a per-function edge cap that logs any dropped edges. All layers are BasicBlock → BasicBlock edges in the single CodeRelation table, keyed by type; there is no Function → BasicBlock edge — the symbol↔block join is reconstructed from the BasicBlock id prefix + line span. The layers build on each other:
- M1 — CFG (#2081):
BasicBlocknodes +CFGedges. Edge kind (seq/cond-true/loop-back/…) rides thereasoncolumn (CFG is oneCodeRelationtype, not one per kind). - M2 — REACHING_DEF (#2082): GEN/KILL def→use data dependence from a pure fixpoint solver; the variable name rides
reason. - M3/M4 — TAINTED / SANITIZES / TAINT_PATH (#2083–#2084): intra- and inter-procedural taint (source→sink) — the
explaintool's data. - M5 — CDG (#2085): Ferrante control dependence over a Cooper–Harvey–Kennedy post-dominator tree (the EXIT-rooted reverse CFG); branch sense (
'T'/'F') ridesreason. A CFG whose EXIT is unreachable from some block is skipped for CDG (post-dominance would be unsound) while its CFG/REACHING_DEF layers are kept. - M6 — read surface (#2086): the
pdg_queryMCP tool answers "what gates X?" (CDG,mode: controls) and "where does Y flow?" (REACHING_DEF,mode: flows);explainis the taint consumer. Both are always anchored +LIMIT-bounded (LadybugDB has no rel-property index) and share oneresolveBlockAnchorhelper. These PDG edge types are deliberately kept out of the defaultVALID_RELATION_TYPES/ web schema.
See core/ingestion/cfg/ (emit + the pure CFG / post-dominator / control-dependence / reaching-defs / taint passes) and mcp/local/local-backend.ts (_pdgQueryImpl, _explainImpl, the shared resolveBlockAnchor).
ScopeResolver contract
Single interface a language implements to plug into the pipeline. Contract fully documented in scope-resolution/contract/scope-resolver.ts.
| Hook | Purpose |
|---|---|
languageProvider |
Base LanguageProvider (tree-sitter query, emitScopeCaptures, import/binding interpreters, hooks) |
populateOwners(parsed) |
Fill deferred ownerId fields on method defs (captures can't always know the owning class at parse time) |
buildMro(graph, parsed, nodeLookup) |
Produce mroByClassDefId: Map<DefId, DefId[]> — C3, Ruby-mixin, or first-wins per language |
resolveImportTarget(target, fromFile, allFiles) |
(rawImportPath, sourceFile) → targetFilePath (PEP-328 for Python, etc.) |
mergeBindings(existing, incoming, scopeId) |
Shadowing / LEGB precedence |
arityCompatibility |
Provider consumed by registry during MethodRegistry.lookup Step 2 |
importEdgeReason |
Confidence-tier string for IMPORTS edge reason field |
propagatesReturnTypesAcrossImports? |
Opt out of cross-file return-type propagation (default on) |
fieldFallbackOnMethodLookup? |
Statically-typed languages turn this OFF — the heuristic over-connects (default on) |
unwrapCollectionAccessor? |
Property-style collection views (data.Values on Dictionary-like receivers) — default off |
collapseMemberCallsByCallerTarget? |
One CALLS edge per (caller, target) instead of per-site — default off |
populateNamespaceSiblings? |
Cross-file implicit visibility (compiler-implicit namespace sharing) — default off; ctx carries treeCache |
hoistTypeBindingsToModule? |
Walk up to Module scope when looking up a method's return-type typeBinding — default off; enable only when bindings are stored at module level |
Per-language registration
- Implement
ScopeResolverinlanguages/<lang>/scope-resolver.ts. - Add entry to
SCOPE_RESOLVERSinscope-resolution/pipeline/registry.ts.
CI auto-discovers the set via tsx. No workflow edit required.
Code references
| Module | Purpose |
|---|---|
scope-resolution/contract/scope-resolver.ts |
ScopeResolver interface + shared types |
scope-resolution/pipeline/run.ts |
Generic orchestrator |
scope-resolution/pipeline/phase.ts |
Pipeline-phase wrapper (deps: parse, structure) |
scope-resolution/pipeline/registry.ts |
SCOPE_RESOLVERS map |
scope-resolution/passes/*.ts |
Reference-resolution passes (receiver-bound, free-call fallback, compound-receiver, MRO, cross-file return-type propagation) |
scope-resolution/graph-bridge/*.ts |
CLI-local translation from resolved references → KnowledgeGraph edges |
scope-resolution/scope/*.ts |
Generic scope-chain walkers + namespace targets |
scope-resolution/workspace-index.ts |
Build-once O(1) lookup index |
languages/python/index.ts |
Python ScopeResolver hooks + known-limitation docs |
languages/python/captures.ts |
emitPythonScopeCaptures (honors cross-phase Tree cache) |
languages/csharp/index.ts |
C# ScopeResolver hooks + known-limitation docs |
languages/csharp/captures.ts |
emitCsharpScopeCaptures (honors cross-phase Tree cache) |
languages/csharp/namespace-siblings.ts |
Cross-file implicit-namespace visibility hook (reads treeCache) |
Performance notes
- Cross-phase Tree cache: the orchestrator's
treeCache(RunScopeResolutionInput.treeCache) lets a scope-resolution per-language hook (emitScopeCaptures) reuse a tree instead of re-parsing. Workers leave it empty — Trees can't cross MessageChannels — so in normal (worker-pool) runs scope-resolution does NOT rely on it: workers serialize each file'sParsedFile(+ capture side-channel) and stream them in, so scope-resolution consumes the pre-extracted artifact rather than re-parsing on the main thread (§ Chunked parse-and-resolve).PROF_SCOPE_RESOLUTION=1emits hit/miss counters and a worker-engaged warning. - Typed relationship iteration: heritage + MRO walk only the EXTENDS / IMPLEMENTS / HAS_METHOD edges via
iterRelationshipsByType, not the full relationship map. - Workspace-resolution-index: O(1)
findOwnedMember/findExportedDef/classScopeByDefIdbuilt once per run. - SCC-ordered cross-file return-type propagation (PR #1050):
propagateImportedReturnTypeswalksindexes.sccsin reverse-topological order (leaves first), so multi-hop alias chains likemodels.User → service.user → app.usercollapse to the terminal class in a single linear pass. Within each importer, the source module'stypeBindingsis chain-followed BEFORE mirroring (so we mirror terminal types, not intermediate refs), and the importer's owntypeBindingsis chain-followed AFTER mirroring (so localconst x = importedFn()resolves before downstream importers run). Cyclic SCCs reach a partial fixpoint within a single pass without iterating to convergence — see thets-circularcross-file-binding fixture which only asserts pipeline-no-throw. PROF output (PROF_SCOPE_RESOLUTION=1) splitsfinalizefrompropagateso quadratic regressions in the chain-follow surface independently.
Language-agnostic graph feeding
16 languages → single unified graph. Four abstraction layers:
Unified Graph Schema (44 node types, 21 relationship types)
↑
Scope-Resolution Pipeline (registry lookup + 3-tier import resolution + MRO)
↑
Language Providers (import semantics, type config, export checker, MRO strategy)
↑
Tree-Sitter Queries (per-language S-expressions, unified capture tags)
Language providers
Each language implements LanguageProvider (language-provider.ts). Key fields:
| Field | Purpose |
|---|---|
id, extensions |
Language identity and file matching |
treeSitterQueries |
S-expression queries for AST extraction |
importSemantics |
named / wildcard-leaf / wildcard-transitive / namespace |
importResolver |
Language-specific path → file resolution |
exportChecker |
Public/exported symbol detection |
typeConfig |
Type annotation extraction rules |
mroStrategy |
first-wins / c3 / none |
16 providers in languages/index.ts via satisfies Record<SupportedLanguages, LanguageProvider> — missing a language is a compile error.
Unified capture tags
Per-language tree-sitter queries use different AST node names but produce the same semantic capture tags: @definition.class, @definition.function, @call.name, @import.source, @reference.inherits. Downstream extraction needs no language branching. Defined in tree-sitter-queries.ts.
Import resolution
Per-language import resolution uses the configs + factory pattern (like call/method/class extractors). Each language declares an ImportResolutionConfig in import-resolvers/configs/, listing an ordered chain of ImportResolverStrategy functions. createImportResolver() (in resolver-factory.ts) composes them: first non-null result wins. Low-level helpers shared across strategies live alongside the configs in import-resolvers/ (e.g. go.ts, rust.ts, python.ts).
Unified 3-tier algorithm (model/resolution-context.ts), per-language importSemantics controls which tier activates:
| Tier | Confidence | Mechanism |
|---|---|---|
| 1 — same-file | 0.95 | Symbol table for caller's file |
| 2 — import-scoped | 0.9 | NamedImportMap chains (named) or all files in importMap (wildcard) |
| 3 — global | 0.5 | O(1) index lookups: class, impl, callable. Fallback only |
| Import strategy | Languages | Behavior |
|---|---|---|
named |
TS, JS, Java, C#, Rust, PHP, Kotlin | Only explicitly imported names visible |
wildcard-leaf |
Go, Ruby, Swift, Dart | Whole-package import, no transitive re-exports |
wildcard-transitive |
C, C++ | #include closure chains through re-exports |
namespace |
Python | Module aliases resolved at call site |
Chunked parse-and-resolve
parse processes files in ~20 MB byte-budget chunks to bound memory. Per chunk:
- Worker pool dispatches files (the sole parse path — there is no sequential fallback;
skipWorkers,--workers 0, andGITNEXUS_WORKER_POOL_SIZE=0are rejected with an actionable error) - Each worker: detect language → load grammar → run queries → return unified
ParseWorkerResult - Synthesize wildcard bindings (
wildcard-synthesis.ts) - Resolve imports
- Collect
BindingAccumulatorentries for cross-file propagation
Inheritance edges are emitted later, by the scope-resolution phase (preEmitInheritanceEdges + emitHeritageEdges), not during parse.
Workers: workers/worker-pool.ts, workers/parse-worker.ts.
Worker-serialized ParsedFiles (#2038). To index very large repos (e.g. the Linux kernel) without OOM, the worker pool is the sole parse path and workers serialize each file's ParsedFile (plus its capture side-channel) in parallel, streaming them to scope-resolution through a disk-backed store. Scope-resolution consumes the pre-extracted artifact instead of re-parsing every file on the main thread — tree-sitter's native input buffers are not GC-reclaimable, so the former main-thread re-parse leaked native memory until the process died. Pool creation is lazy / cache-miss-gated, so a warm all-cache-hit run replays cached worker output without spawning a worker (hence usedWorkerPool can be false even when the repo has parseable files).
Inheritance and MRO
Inheritance is captured by the @reference.inherits tag and emitted by the scope-resolution phase: preEmitInheritanceEdges resolves each base in scope, then emitHeritageEdges writes the EXTENDS/IMPLEMENTS edges. The phase then computes method resolution order via each ScopeResolver's buildMro hook, feeding a MethodDispatchIndex used for owner-scoped lookups. Per-language strategy:
first-wins— Java, C#, C++, TS, Ruby, Goc3— Python (C3 linearization)ruby-mixin— Ruby (mixin-aware linearization)none— single-inheritance languages
Full analysis flow
runFullAnalysis in run-analyze.ts orchestrates everything around the pipeline:
CLI (analyze.ts) → runFullAnalysis(repoPath, options, callbacks)
1. Early exit if lastCommit == HEAD (unless --force) [0%]
2. Cache existing embeddings from prior index [0%]
3. runPipelineFromRepo() → KnowledgeGraph [0-60%]
4. Clean up legacy KuzuDB files [60%]
5. initLbug() → loadGraphToLbug() via CSV streaming [60-85%]
6. Create FTS indexes (File, Function, Class, Method...) [85-90%]
7. Restore cached embeddings (batch insert) [88%]
8. Generate new embeddings if --embeddings [90-98%]
9. Save metadata + register repo + update .gitignore [98-100%]
10. Generate AI context files (AGENTS.md, CLAUDE.md) [100%]
Options: --force (rebuild regardless), --embeddings (opt-in, skipped if >50k nodes), --skipGit, --noStats.
Storage
<repo>/.gitnexus/
├── lbug # LadybugDB database
├── lbug.wal # Write-ahead log
├── lbug.lock # Single-writer lock
└── meta.json # lastCommit, indexedAt, stats
~/.gitnexus/
└── registry.json # Global repo registry (MCP discovery)
Managed by repo-manager.ts.
LadybugDB schema
Defined in lbug/schema.ts. Separate node tables per type, single CodeRelation table.
Node tables: File, Folder, Function, Class, Interface, Method, Constructor, CodeElement, Struct, Enum, Macro, Typedef, Union, Namespace, Trait, Impl, TypeAlias, Const, Static, Property, Record, Delegate, Annotation, Template, Module, Community, Process, Route, Tool, Section, Embedding.
Relation types (CodeRelation.type): CONTAINS, DEFINES, CALLS, IMPORTS, EXTENDS, IMPLEMENTS, HAS_METHOD, HAS_PROPERTY, ACCESSES, METHOD_OVERRIDES, METHOD_IMPLEMENTS, MEMBER_OF, STEP_IN_PROCESS, HANDLES_ROUTE, FETCHES, HANDLES_TOOL, ENTRY_POINT_OF.
Optional --pdg additions (off by default, opt-in via gitnexus analyze --pdg; see Optional CFG/PDG emission above): a BasicBlock node table, plus the PDG relation types CFG, REACHING_DEF, CDG, TAINTED, SANITIZES, and TAINT_PATH on the same CodeRelation table. These are deliberately kept out of the default VALID_RELATION_TYPES / web graph schema — query them via cypher, explain, or pdg_query.
Embeddings and search
Embeddings (src/core/embeddings/): Snowflake arctic-embed-xs (384D). Embeddable: File, Function, Class, Method, Interface. Incremental via SHA1 content hash. Separate Embedding table.
Search (src/core/search/): Hybrid BM25 + semantic vector, merged via Reciprocal Rank Fusion (K=60).
Known limitations
Overloaded method resolution
Node IDs use arity suffix (#<paramCount>): Method:file:Class.method#1 vs #2.
Same-arity disambiguation: type-hash suffix ~type1,type2 when collision detected and type annotations present. Languages without types (Python, Ruby, JS) use arity-only. TS/JS overload signatures excluded (collapse to implementation body). See #651.
C++ const-qualified: $const suffix after type-hash when non-const collision exists: Method:file:Container.begin#0$const.
Generic/template types: type-hash uses rawType (full AST text including generics): ~vector<int> vs ~vector<std::string>.
ID stability: collision-only tags mean IDs change when overloads are added. save#1 becomes save#1~int when save(String) is added.
Variadic matching: confidence 0.7 when one side is variadic and the other has fixed count.
METHOD_IMPLEMENTS confidence tiering:
| Match quality | Confidence |
|---|---|
| Exact parameter types match | 1.0 |
| Arity match, types unavailable | 1.0 |
| Variadic vs fixed | 0.7 |
| Insufficient info | 0.7 |
Related docs
- MIGRATION.md — breaking changes and migration guidance
- RUNBOOK.md — operational commands and recovery
- GUARDRAILS.md — safety boundaries for humans and agents
- TESTING.md — how to run tests
AGENTS.md/CLAUDE.md— agent workflows and tool usage