Repositories

TypeORM repositories expose CRUD and custom queries for an entity. Convenient for simple persistence, but services still need clear business boundaries—not every query belongs in a generic base repository.

					const repo = manager.getRepository(Order);
await repo.find({ where: { status: 'open' }, relations: ['customer'] });
				

On interviews: custom repository methods, `EntityManager` in transactions, when query builder is the better tool.

Common pitfalls: global repository calls inside a transaction bypassing the transactional manager; generic wrappers adding noise without policy.

The trade-off is quick CRUD ergonomics versus transaction-correct access.

Checklist:

• Use transaction-scoped managers.
• Expose use-case queries.
• Avoid generic wrappers with no policy.
• Prefer query builder for complex SQL.