FlatPack is serialization framework used by Perka to make its JPA entities available via REST to JavaScript, iOS, and Android clients.

• Serialize arbitrary JPA object graphs into payloads that can be processed easily in non-Java environments.
• Support role- and principal-based security on property access.
• Integration with jax-rs (specifically Jersey).
• Straightforward code generation of client libraries and documentation.
• Minimize developer friction

• apidoc and apidoc-plugin are used during the maven build process to make JavaDoc strings available to ApiDescriber.
• client provides support code for generated client libraries.
• core contains the serialization logic. The central types are FlatPack, Packer, and Unpacker.
• demo-client and demo-server show a very simple JAX-RS server and how to use generated client code. The demo-client module also contains smoke-tests.
• eclipse-plugin contains an m2eclipse connector for the FlatPack plugins. A pre-built drop-in is available at from the project downloads.
• fast and fast-plugin, the FlatPack Automatic Source Tool, take an ApiDescription and generate client access libraries consisting of DTO objects and API request methods.
• jersey wires FlatPack into Jersey's request dispatch logic. The ApiDescriber type will produce a FlatPack description of the API server's methods and entities.
• search is utility code.

Additional documentation is available in the FlatPack wiki.