Developers

Compose stateful apps from typed bricks.

The Quatrain SDK is fully typed and tree-shakeable. Pick the bricks you need; the runtime stays small.

1 — Install

# npm
npm install @quatrain/core @quatrain/backend-postgres @quatrain/auth-oidc

# pnpm
pnpm add @quatrain/core @quatrain/backend-postgres @quatrain/auth-oidc

# bun
bun add @quatrain/core @quatrain/backend-postgres @quatrain/auth-oidc

# from source (monorepos)
git clone https://github.com/Quatrain/Core.git
git clone https://github.com/Quatrain/CoreUX.git
git clone https://github.com/Quatrain/CoreApps.git
cd Core && bun install

2 — Define a workflow

import { WorkflowStateMachine } from '@quatrain/state-machine';

export const purchaseOrder = new WorkflowStateMachine({
  id: 'purchase-order',
  states: ['draft', 'review', 'approved', 'closed'],
  transitions: [
    { from: 'draft', to: 'review', on: 'submit' },
    { from: 'review', to: 'approved', on: 'approve', guard: 'isManager' },
    { from: 'approved', to: 'closed', on: 'fulfill' },
  ],
});

3 — Deploy anywhere, with Tycho

# Infrastructure & deployment live under the Tycho brand
tycho init my-app
tycho deploy --target kubernetes   # serverless | bare-metal | kubernetes

# Same business logic, any infrastructure — that's the Core promise.

Highlights

Built for serious systems.

TypeScript-first

Strict types across every brick — no any, no leaks.

Three monorepos

Core (backend), CoreUX (frontend), CoreApps (studio & containers).

Reference app

The bookstore example in CoreApps shows a full assembly.

Read the documentation Read the monorepo docs rebuilt nightly by CI

Security audits, signed packages and compliance live on the Corporate page.

Security & trust