gbrain/CONTRIBUTING.md

Contributing to GBrain

Setup

git clone https://github.com/garrytan/gbrain.git
cd gbrain
bun install
bun test

Requires Bun 1.0+.

Project structure

src/
  cli.ts                  CLI entry point
  commands/               CLI-only commands (init, upgrade, import, export, etc.)
  core/
    operations.ts         Contract-first operation definitions (the foundation)
    engine.ts             BrainEngine interface
    postgres-engine.ts    Postgres implementation
    db.ts                 Connection management + schema loader
    import-file.ts        Import pipeline (chunk + embed + tags)
    types.ts              TypeScript types
    markdown.ts           Frontmatter parsing
    config.ts             Config file management
    chunkers/             3-tier chunking (recursive, semantic, llm)
    search/               Hybrid search (vector, keyword, hybrid, expansion, dedup)
    embedding.ts          OpenAI embedding service
  mcp/
    server.ts             MCP stdio server (generated from operations)
  schema.sql              Postgres DDL
skills/                   Fat markdown skills for AI agents
test/                     Unit tests (bun test, no DB required)
test/e2e/                 E2E tests (requires DATABASE_URL, real Postgres+pgvector)
  fixtures/               Miniature realistic brain corpus (13 files)
  helpers.ts              DB lifecycle, fixture import, timing
  mechanical.test.ts      All operations against real DB
  mcp.test.ts             MCP tool generation verification
  skills.test.ts          Tier 2 skill tests (requires OpenClaw + API keys)
docs/                     Architecture docs

Running tests

bun test                          # all tests (unit + E2E skipped without DB)
bun test test/markdown.test.ts    # specific unit test

# E2E tests (requires Postgres with pgvector)
docker compose -f docker-compose.test.yml up -d
DATABASE_URL=postgresql://postgres:postgres@localhost:5434/gbrain_test bun run test:e2e

# Or use your own Postgres / Supabase
DATABASE_URL=postgresql://... bun run test:e2e

Building

bun build --compile --outfile bin/gbrain src/cli.ts

Adding a new operation

GBrain uses a contract-first architecture. Add your operation to one file and it automatically appears in the CLI, MCP server, and tools-json:

1. Add your operation to src/core/operations.ts (define params, handler, cliHints)
2. Add tests
3. That's it. The CLI, MCP server, and tools-json are generated from operations.

For CLI-only commands (init, upgrade, import, export, files, embed):

1. Create src/commands/mycommand.ts
2. Add the case to src/cli.ts

Parity tests (test/parity.test.ts) verify CLI/MCP/tools-json stay in sync.

Adding a new engine

See docs/ENGINES.md for the full guide. In short:

1. Create src/core/myengine-engine.ts implementing BrainEngine
2. Add to engine factory in src/core/engine.ts
3. Run the test suite against your engine
4. Document in docs/

The SQLite engine is designed and ready for implementation. See docs/SQLITE_ENGINE.md.

Welcome PRs

• SQLite engine implementation
• Docker Compose for self-hosted Postgres
• Additional migration sources
• New enrichment API integrations
• Performance optimizations