Why Stingerloom?

• Decorator-first — Define entities, relations, hooks, and validation with TypeScript decorators. Column types are inferred automatically.
• Multi-tenancy built in — Layered metadata system (inspired by Docker OverlayFS) with AsyncLocalStorage-based context isolation. Zero cross-tenant leakage by design.
• Three databases, one API — MySQL, PostgreSQL, and SQLite share the same EntityManager interface. Switch drivers without rewriting queries.
• Schema Diff migrations — Compare live database state against entity metadata and auto-generate migration code.
• NestJS-ready — First-party module with @InjectRepository, @InjectEntityManager, and multi-DB named connections.

Quick Start

npm install @stingerloom/orm reflect-metadata
npm install pg        # or mysql2, better-sqlite3

import { EntityManager, Entity, PrimaryGeneratedColumn, Column } from "@stingerloom/orm";

@Entity()
class Post {
  @PrimaryGeneratedColumn()
  id!: number;

  @Column()
  title!: string;
}

const em = new EntityManager();
await em.register({ type: "postgres", entities: [Post], synchronize: true, /* ... */ });

const post = await em.save(Post, { title: "Hello World" });
const found = await em.findOne(Post, { where: { id: post.id } });

See the Getting Started guide for full setup instructions.

Features

| Category | Highlights | |----------|------------| | Modeling | @Entity, @Column, @ManyToOne, @OneToMany, @ManyToMany, @OneToOne, eager/lazy loading | | Querying | find, findOne, findWithCursor, findAndCount, Query Builder with JOIN/GROUP BY/HAVING | | Mutations | save, update, delete, softDelete, restore, upsert, batch operations | | Transactions | @Transactional decorator, manual BEGIN/COMMIT/ROLLBACK, savepoints, isolation levels | | Multi-tenancy | Layered metadata (OverlayFS model), MetadataContext.run(), PostgreSQL schema isolation, TenantMigrationRunner | | Migrations | SchemaDiff auto-detection, MigrationGenerator, CLI runner | | Observability | N+1 detection, slow query warnings, EXPLAIN analysis, EntitySubscriber events | | Validation | @NotNull, @MinLength, @MaxLength, @Min, @Max | | Infrastructure | Connection pooling, read replicas, retry with backoff, per-query timeout, graceful shutdown | | NestJS | StinglerloomOrmModule.forRoot/forFeature, @InjectRepository, @InjectEntityManager, multi-DB connections |

Database Support

| | MySQL | PostgreSQL | SQLite | | ---------------- | :---: | :--------: | :----: | | CRUD | ✓ | ✓ | ✓ | | Transactions | ✓ | ✓ | ✓ | | Schema Sync | ✓ | ✓ | ✓ | | Migrations | ✓ | ✓ | ✓ | | ENUM | ✓ | ✓ (native) | — | | Schema Isolation | — | ✓ | — | | Read Replica | ✓ | ✓ | — |

Examples

Four NestJS example projects are included in examples/:

| Project | Description | |---------|-------------| | nestjs-cats | CRUD, relations, soft delete, cursor pagination, EntitySubscriber | | nestjs-blog | ManyToMany, upsert, 59 e2e tests | | nestjs-todo | Minimal CRUD with npm package verification | | nestjs-multitenant | PostgreSQL schema-based tenant isolation |

Contributing

Contributions are welcome. Please open an issue first to discuss what you'd like to change.

License

MIT