Installation

Reflow is ESM-only and ships TypeScript types. Node.js 18.18 or newer is required (the first Node 18 release with Symbol.asyncDispose, used by the result stream).

Install

bun

# Uses the built-in bun:sqlite module — no native dependencies
bun add reflow-ts

npm

npm install reflow-ts better-sqlite3

pnpm

pnpm add reflow-ts better-sqlite3

Pick a storage adapter

Reflow's storage is pluggable. Two SQLite adapters ship in the box — pick the one for your runtime:

// Bun — zero native dependencies (built-in bun:sqlite)
import { SQLiteStorage } from 'reflow-ts/sqlite-bun'
const storage = new SQLiteStorage('./reflow.db')

// Node.js — uses better-sqlite3 (a native addon), WAL mode
import { SQLiteStorage } from 'reflow-ts/sqlite-node'
const storage = new SQLiteStorage('./reflow.db')

On Node, better-sqlite3 is an optional peer dependency — install it alongside Reflow. On Bun, nothing extra is needed.

better-sqlite3 13 requires Node 22

Reflow supports Node 18.18+, but better-sqlite3 13 raises its own floor to Node 22, so a plain npm install better-sqlite3 fails on Node 18–21 with an engine error.

Reflow's peer range is >=9, so pin the older major there:

npm install reflow-ts better-sqlite3@12   # Node 18-21
npm install reflow-ts better-sqlite3      # Node 22+

Only the reflow-ts/sqlite-node adapter is affected. Bun's adapter and the node:sqlite adapter have no native dependency — though the latter needs Node 22.5+ for its own reasons.

See Storage for the in-memory adapter and how to write your own.

Pick a schema library

Reflow validates workflow input with Standard Schema, so any compatible library works:

bun add zod        # or
bun add valibot    # or
bun add arktype    # or any Standard Schema-compatible library

Next: Quick Start walks through defining and running a workflow.