What BFF Blocks does
Turn a response into ready-to-paste blocks for Zod, tRPC, GraphQL, NestJS, Fastify, TanStack Query, and RTK Query.
Also searched as bff, backend for frontend, zod, trpc, graphql, nestjs, fastify, tanstack query.
Infer the response shape and its formats
Name the nested types and order them by dependency
Emit one block per BFF library
One shape, seven restatements
A backend-for-frontend spends most of its code saying the same shape in a different dialect. The shape is inferred once here and rendered into each library's idiom.
A draft, not a contract
One payload cannot show which fields are optional or what the error responses look like. Every field arrives required — relax the ones that can legitimately be absent before clients depend on it.
BFF Blocks FAQ
Does jsontools.me upload my JSON?
No. The document is parsed and processed by json-buf inside a dedicated WebAssembly worker on your device.
Does it work offline?
Yes. After the application shell and engine have loaded once, the installable PWA keeps the tools available without a network connection.