- Prisma Client is now ESM‑only by default, with 90% smaller bundles and up to 3× faster queries; requires explicit adapter or accelerateUrl, and removes legacy client instantiation options.
- A large set of implicit commands, CLI flags, and deprecated engines (including MongoDB support) have been removed, making configuration stricter (e.g., prisma.config.ts required, env vars no longer auto‑loaded).
- New features include @map support for enum members, an updated Prisma Studio in the CLI, and native connection pooling for Prisma Postgres with a serverless driver.