oRPC is a TypeScript framework for building typesafe APIs with end-to-end type safety across client and server.
The framework solves the problem of maintaining type consistency between API contracts and their implementations across distributed systems. It works by establishing a single source of truth through contract definitions that both server and client code reference. The core approach separates concerns into distinct packages: a contract layer that defines API shapes, a server layer that implements those contracts with middleware and context support, and a client layer that consumes APIs while preserving type information. The framework also provides OpenAPI compatibility, allowing generated or existing OpenAPI specifications to be converted into oRPC contracts.
Teams should adopt oRPC when building TypeScript-based applications where type safety across the API boundary is a priority. It suits projects using modern JavaScript runtimes and frameworks including Node.js, Deno, Bun, Next.js, and Cloudflare Workers, with client-side support for React, Vue, Svelte, and SolidJS. The contract-first approach makes it particularly valuable for teams maintaining multiple client implementations or those integrating with existing OpenAPI-documented services.
The project shows consistent development activity with regular updates across its core packages. The codebase maintains high test coverage and performance monitoring through continuous integration. The maintainers actively engage with the community through a dedicated Discord channel and provide comprehensive documentation covering all major features and use cases.
