Icyapi

Icyapi is an open-source API framework and toolkit designed to simplify the development, testing, and consumption of application programming interfaces. It provides a schema-first design that supports multiple API styles, including REST, GraphQL, and gRPC, allowing developers to define data models and operations in a single source of truth and generate server stubs and client bindings across languages.

The architecture centers on a modular, plugin-based core. Core features include an adaptable routing and middleware pipeline, automatic client code generation, request validation, and built-in security primitives such as authentication, authorization, and rate limiting. The framework emphasizes interoperability through support for common API specifications and formats, including OpenAPI for REST, Protocol Buffers for gRPC, and GraphQL SDL.

Icyapi is designed to be language-agnostic at the interface level, with server runtimes and client libraries available for major programming languages, enabling teams to use their existing stacks. It aims to streamline API evolution by providing versioned schemas and tooling for migrations, testing, and observability, including logging, tracing, and metrics.

The project is distributed under a permissive open-source license and maintained by a community of contributors. Documentation, example projects, and a public issue tracker accompany releases. In practice, icyapi targets microservices architectures and API gateways, offering a unified approach to defining and consuming interfaces across heterogeneous services.