Your API Is Type-Safe Only When Postgres Agrees

Abhishek tiwari — Wed, 23 Sep 2026 10:47:23 +0000

Type Safety Across the Stack: Make Postgres, Node.js, and React Agree

The false guarantee: TypeScript interfaces describe intent, not runtime data.
Postgres as the first contract: constraints, role checks, foreign keys, and migration tests.
A typed query boundary: map generated row types into narrow application DTOs without leaking table entities.
Node.js validation: validate inputs once, serialize outputs, and standardize errors.
React integration: shared response types, a typed fetch wrapper, and explicit state models.
CI enforcement: type checking, migration validation, contract tests, and no-any rules.

Code snippet ideas:

Finish with a migration checklist for one signup or authorization flow.