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@schema-weaver/migration-engine

PostgreSQL schema introspection, diff, DDL generation, and safe migration execution.

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Topic	Description
Architecture	7-layer engine design and data flow
Supported-Objects	Full 37 object types with coverage %
API-Reference	All public methods with parameters
Safe-Migration-Patterns	3-step patterns for safe migrations
Risk-Assessment	5-level risk classification system
PG-Version-Matrix	Feature support across PG10-18
Testing	6-layer test strategy and results

Why This Engine

No existing open-source tool covers 37 PostgreSQL object types:

Tool	Coverage	Limitation
pgAdmin	UI only	No programmatic API
Atlas	~15 types	Missing views, functions, triggers, policies
Prisma	~10 types	Ignores behavioral objects

This engine: 37 types, 98.5% property coverage

Installation

npm install @schema-weaver/migration-engine pg

Quick Start

import pg from 'pg';
import { SwMigrationEngine } from '@schema-weaver/migration-engine';

const pool = new pg.Pool({ host: 'localhost', database: 'mydb' });
const engine = new SwMigrationEngine();

const snapshot = await engine.introspect(pool);
const diff = engine.diff(desired, snapshot);
const plan = engine.plan(diff);

if (!plan.blocked) {
  await engine.execute(pool, plan);
}

License

Business Source License 1.1 (BSL) — free for development, commercial license required for production.

Built by Schema Weaver — the AI-native PostgreSQL workspace for developers.