mongreldb-node

High-performance Node.js bindings for MongrelDB via NAPI, with native in-process storage, sub-ms writes, and hybrid indexing. It follows the better-sqlite3 model: no HTTP latency, so the ~8 µs single-row write isn't dwarfed by a network round-trip. Exposes a typed object/method interface (not SQL); TypeScript types are generated at build time.

This crate is built separately from the Rust workspace (it targets the NAPI ABI and needs Node.js tooling). It is excluded from cargo {test,clippy} --workspace.

Build

Requires Node.js ≥ 16 and @napi-rs/cli:

cd crates/mongreldb-node
npm install
npm run build          # → mongreldb.<platform>.node + index.d.ts

API sketch (generated index.d.ts)

class Database {
  static withPath(path: string): Database
  static open(path: string): Database
  createTable(name: string, schema: SchemaSpec): bigint
  table(name: string): TableHandle
  begin(): Transaction
  createProcedure(spec: ProcedureSpec): bigint
  createOrReplaceProcedure(spec: ProcedureSpec): bigint
  dropProcedure(name: string): void
  procedures(): ProcedureInfo[]
  procedure(name: string): ProcedureInfo | null
  callProcedure(name: string, opts?: ProcedureCallOptions): ProcedureCallResult
  callProcedureAsync(name: string, opts?: ProcedureCallOptions): Promise<ProcedureCallResult>
  sql(sql: string): Promise<Buffer>
  close(): void
}

class TableHandle {
  put(cells: Cell[]): PutResult
  putBatch(rows: Cell[][]): PutResult[]
  bulkLoadTyped(columns: TypedColumn[]): bigint
  commit(): bigint
  flush(): bigint
  count(): bigint                        // O(1)
  countWhere(conditions: ConditionSpec[]): bigint
  get(rowId: bigint): RowJs | null
  query(conditions: ConditionSpec[]): RowJs[]   // hybrid: bitmap ∩ range ∩ FM ∩ HNSW
  queryArrow(conditions: ConditionSpec[]): Buffer
}

Hybrid query - the differentiator

query intersects row-id sets from any combination of the six index types in a single in-process call - something no HTTP vector DB or SQL FTS pipeline can do in one hop:

db.query([
  { kind: ConditionKind.Ann, columnId: 5, embedding: queryVec, k: 50 },
  { kind: ConditionKind.FmContains, columnId: 2, text: "rome" },
  { kind: ConditionKind.BitmapIn, columnId: 3, values: ["eu", "na"] },
])

Notes

• Row ids / counts / epochs cross the FFI as JS BigInt (u64), so the full 64-bit id space is lossless.
• Most blocking table methods also expose *Async Promise variants that run on the NAPI blocking pool.