NestJS 12 is out: ESM, Standard Schema validation and a new toolchain

What's new

• ESM. Core packages ship as ESM; existing CommonJS projects keep working through require(esm).
• Standard Schema. @Body(), @Query() and other decorators accept a schema — Zod, Valibot and ArkType work.
• Tooling. New ESM projects default to Vitest and oxlint, monorepos build with Rspack instead of webpack; CommonJS projects stay on Jest and ESLint.
• Observability and diagnostics: structured logging, machine-readable error codes, route conflict diagnostics and the @nestjs/observe SDK.
• Microservices and GraphQL: NATS v3, GraphiQL as the default IDE, request-scoped WebSocket gateways.

What breaks when upgrading

• Node.js 20.19+ or 22.12+ is required.
• subscriptions-transport-ws is removed — move GraphQL subscriptions to a current transport.
• NATS microservices move to the v3 client (@nats-io/transport-node).
• See the official migration guide for the full list.

How to upgrade

1. Update all @nestjs/* packages to the same version and check the migration guide.
2. Check the Node.js version on servers and in CI.
3. Run the API unit and e2e tests before rolling out.

We build and maintain NestJS and Node.js backends: we will upgrade the framework and dependencies, cover it with tests and roll out without downtime.

Source: official release announcement.