EngramGraph

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Open-source code + knowledge graph memory engine, fusing SAGE self-evolving graph memory with CodeGraph structural code understanding.

License: MIT · Runtime: Node.js ≥ 22 · Graph DB: Kuzu (embedded, Cypher) · No LLM required (deterministic)

EngramGraph is a general-purpose engine. The defaults ("single repo + generic markdown + git signals") work out of the box for any project; project-specific behaviour is supplied through pluggable adapters.

Why a graph?

Vector search ("find me similar memories") and graph traversal ("find me structurally related nodes") are complementary. EngramGraph adds the graph half:

"I want to change execute() → the engine walks: callers → related specs → the decisions behind them."

Install

npm install engramgraph

Or run the CLI without installing:

npx engramgraph index ./src

Quickstart

# 1. Index a repo into the graph (code + optional docs)
egr index ./src --docs

# 2. "What breaks if I change this function?"
egr callers myFunction --depth 2

# 3. "Which decisions sit behind this spec?"
egr impact SPEC-001

The graph DB lives at ENGRAM_DB (default ./.engram/graph.db). Full command reference: docs/CLI.md.

Embedded usage (in-process, zero HTTP)

import { EmbeddedClient } from "engramgraph";

const client = new EmbeddedClient();   // SingleRepoIsolation by default
await client.init();                   // opens graph.db + ensures schema
const rows = await client.query("MATCH (f:Function) RETURN f.name AS name");
await client.close();

REST usage

import { createServer, GraphConnection } from "engramgraph";

const conn = GraphConnection.open("./.engram/graph.db");
const app = createServer({ connection: conn });   // Hono app; routes under /graph/*
// GET /health → { status: "ok" }

Or just egr serve --port 3000. API reference: docs/API.md.

Three modes

| Mode | Entry | Use case | |------|-------|----------| | Embedded | EmbeddedClient | Same-process, zero HTTP overhead (e.g. same-process integration) | | REST | createServer() (Hono) / egr serve | Standalone graph service; routes under /graph/* | | MCP | egr-mcp (stdio) / egr mcp | Plug-and-play for coding assistants (Claude Code, Codex, Cursor, ...) |

MCP — use EngramGraph from a coding assistant

EngramGraph ships an MCP server (stdio) exposing 5 tools — index_code, index_docs, call_chain, impact_analysis, ingest_feedback — so any MCP-capable assistant can use it as a code + knowledge graph. Zero LLM, deterministic, no Docker.

# Claude Code, from an installed package:
claude mcp add egr -- npx egr-mcp

Full setup (Claude Code / Codex / Cursor / Windsurf), the 5 tools, and an example flow: docs/MCP.md.

Core vs Adapter boundary

| Layer | Contents | External usability | |-------|----------|--------------------| | Generic Core | CodeGraph (tree-sitter → graph), SAGE evolution, Kuzu abstraction, REST/MCP/Embedded modes, node-sdk | Zero project-specific dependency | | Pluggable Adapters (interfaces) | (1) knowledge source (2) isolation model (3) SAGE signal source | Core ships interface + a generic default |

The three adapters

1. Knowledge source — KnowledgeSource → { nodes, edges }. Default: MarkdownKnowledgeSource parses any front-matter markdown (id / title / status + [[ref]] links) into generic Doc nodes.
2. Isolation model — IsolationModel.dbPath(ctx) → string. Default: SingleRepoIsolation (one graph.db, no org concept). Opt-in: OrgProjectIsolation (org-{orgId}/project-{projectId}/graph.db).
3. SAGE signal source — SignalSource → FeedbackEvent[]. Defaults: GitHistorySignalSource, TestExitCodeSignalSource.

Graph schema

6 node tables — Function, Class, Module, Spec, Decision, Doc. 7 relationship tables — CALLS, IMPORTS, DEFINES, IMPLEMENTS, IMPACTS, SUPERSEDES, REFERENCES. See docs/API.md for the full DDL and the front-matter schema that drives knowledge ingestion.

Status

• [x] Phase 1 — scaffold (MIT, Node 22, ESM+CJS, tsup, vitest), Kuzu abstraction + idempotent schema (6 NODE / 7 REL tables), three adapter interfaces + generic defaults, Hono GET /health, EmbeddedClient
• [x] Phase 2 — CodeGraph: tree-sitter extractor/indexer, cross-file CALLS resolution, scope-qualified function ids
• [x] Phase 3 — KnowledgeGraph: front-matter markdown → Spec / Decision + IMPACTS / SUPERSEDES edges
• [x] Phase 4 — SAGE evolution layer: confidence feedback (STEP 0.25, floor 0.1), topByConfidence, rankedImpact
• [x] Phase 5 — REST routes (/graph/call-chain, /graph/impact-analysis, /graph/ingest), MCP server (5 tools), standalone egr CLI

Contributing

See CONTRIBUTING.md for dev setup, the build/test/health loop, and the kuzu + tree-sitter teardown caveat. Changes are tracked in CHANGELOG.md.

License

MIT — see LICENSE.