tempest-db-js

tempest-db-js

Type-safe, class-based ORM for TypeScript — SQLAlchemy 2.0 ergonomics for the JS/TS world. Foundation package for the future tempest-ts-sdk.

Documentation: Português (BR) · English (US)

Status: alpha (v0.3.0), published on npm. The full path works end-to-end — declarative models, typed query builder (aggregations, DISTINCT, upsert), real SQLite + PostgreSQL execution, a MySQL dialect, joins, relations, Alembic-style migrations (sync + async runner) with a tempest-db CLI, a typed BaseRepository, and an opt-in active-record layer. The public API may still shift before v1.0.

Why tempest-db-js

You define a model once, as a class — tempest-db-js infers everything else:

import { Model, column, type InferModel, type InferInsert } from "tempest-db-js";

class User extends Model {
  static tablename = "users";
  id = column.integer().primaryKey();
  name = column.text().notNull();
  age = column.integer().notNull();
  nickname = column.text();                 // nullable
  createdAt = column.timestamp().default(new Date());
}

type UserRow    = InferModel<typeof User>;
// { id: number; name: string; age: number; nickname: string | null; createdAt: Date | null }

type UserInsert = InferInsert<typeof User>;
// { name: string; age: number; nickname: string | null; id?: number; createdAt?: Date | null }

No manual interface, no codegen step, no schema/type drift. The class is the source of truth — just like SQLAlchemy's declarative Mapped[...].

The TypeScript reality

SQLAlchemy reads Mapped[int] at runtime via descriptors; TypeScript erases types at compile time. tempest-db-js bridges this by making each column a runtime-typed builder (column.integer()) that carries both its SQL type (runtime) and its static type (inference). You get class-based ergonomics and strong query-result inference — the trade-off being that returned rows are inferred plain objects, not active-record class instances (a post-MVP stretch goal).

Install & run

npm install tempest-db-js
# SQLite needs no extra driver (uses Node's built-in node:sqlite).
# For PostgreSQL: npm install postgres

import { Model, column, select, insert, createSyncEngine } from "tempest-db-js";

class Task extends Model {
  static tablename = "tasks";
  id = column.integer().primaryKey();
  title = column.text().notNull();
  done = column.boolean().notNull();
}

const engine = createSyncEngine("sqlite://:memory:");
const session = engine.session();

session.execute(insert(Task).values({ title: "ship docs", done: false }));

const pending = session.execute(select(Task).where({ done: false })).all();
//    ^ inferred as { id: number; title: string; done: boolean }[] — no annotation

Real execution is tested against a live SQLite database (node:sqlite) — type coercion, RETURNING, transactions, and rollback included. PostgreSQL runs via postgres.js.

Sessions and engines are disposable — using session = engine.session() (or await using engine = createEngine(...)) closes the driver/pool automatically at scope exit.

Beyond CRUD

Typed extras, each with a docs recipe:

• Aggregations — select(Order).aggregate(["status"], { n: count(), total: sum("amount") }) → rows typed as { status; n; total }. Plus .distinct().
• Upsert — insert(Row).values(...).onConflictDoUpdate(["key"], { ... }) / .onConflictDoNothing(["key"]) (portable SQLite PostgreSQL).
• Active-record (opt-in) — activeRecord(User, session) → save/update/delete/reload over .data; the plain-object default is unchanged.
• Query logging & errors — createEngine(url, { onQuery }) traces every statement; a failed statement throws QueryExecutionError carrying the SQL + params.

Migrations CLI

Alembic-style migrations ship with a tempest-db binary. Point it at a config that exports your driver, dialect, migrations, and models:

// tempest-db.config.mjs
import { defineMigrationConfig } from "tempest-db-js/migrations";
import { NodeSqliteDriver } from "tempest-db-js";
import { migrations } from "./migrations/index.js";
import { User } from "./models.js";

export default defineMigrationConfig({
  driver: NodeSqliteDriver.open("app.db"),
  dialect: "sqlite",
  migrations,
  models: [User],
});

npx tempest-db revision -m "add users" --autogenerate   # detects renames interactively
npx tempest-db upgrade                                   # apply pending migrations
npx tempest-db current | history | heads | check

HTTP integration recipes (Hono, Express, Fastify) live in the docs.

Roadmap

See ROADMAP.md. Shipped (v0.3.0): SQLite + PostgreSQL execution (both tested in CI, Postgres against a live database), a MySQL dialect, joins, relations, sync + async migration runners with a tempest-db CLI, repository, aggregations/upsert, opt-in active-record. Next: MySQL execution in CI + RETURNING round-trip, async CLI wiring, then tempest-ts-sdk.

Development

npm install
npm run test:types   # tsc --noEmit — the type-level test suite
npm test             # vitest runtime tests
npm run build        # tsup → dual ESM + CJS + .d.ts
npm run bench        # SQLite benchmark vs Drizzle/Kysely (see BENCHMARKS.md)

License

MIT