Open-source alternatives to Orpc

ts-rest is a TypeScript toolkit for building type-safe APIs by defining a shared contract that connects client and server code. The core idea is to specify endpoints, methods, request and response shapes in a single contract, then use that contract to generate fully typed clients and enforce server implementations that match the contract at compile time. The project provides a way to consume remote APIs through a client that infers request and response shapes from the shared contract, offering autocompletion and compile-time checks. On the server side, it enforces that handlers return correct

This project is an end-to-end type-safe API framework designed to synchronize data structures between frontend and backend codebases without the need for manual code generation. By leveraging TypeScript’s type inference, it allows developers to invoke server-side functions directly from the client as if they were local methods. This remote procedure call approach abstracts away the complexities of HTTP verbs and URL structures, streamlining the full-stack development workflow into a unified experience. The framework distinguishes itself through a modular router architecture that organizes bac

Wasp is a declarative full-stack web framework that enables developers to build and deploy applications by defining their architecture in a centralized configuration. By using a high-level specification, the framework automates the orchestration of frontend, backend, and database components, ensuring that infrastructure concerns like routing, authentication, and data modeling are handled consistently across the entire stack. The framework distinguishes itself through its compiler-driven approach, which translates declarative configurations into cohesive, production-ready codebases. It provide

Orval is an OpenAPI-to-TypeScript code generator that produces fully typed API clients, data-fetching hooks, mock data, validation schemas, and server handlers from OpenAPI or Swagger specifications. It reads any YAML or JSON API specification and generates TypeScript interfaces, HTTP request functions, and framework-specific integration code that ensures compile-time correctness for all API calls. The project distinguishes itself by generating production-ready data-fetching hooks for React Query, Vue Query, Svelte Query, Solid Query, Angular, and SWR, complete with automatic cache invalidati

TypeSpec is a language for defining cloud API shapes and generating OpenAPI, JSON Schema, and client/server code from a single source of truth. It functions as a protocol-agnostic API designer that models REST, gRPC, and other API protocols using a unified, extensible syntax, with a decorator-based metadata system for attaching metadata, validation rules, and lifecycle visibility to API models and operations. The compiler produces OpenAPI 3.0 specifications and other artifacts, and the tool supports declaring API versions and tracking changes to models, properties, and operations across releas

Refit is a type-safe REST client for .NET that transforms API definitions into live interfaces. It functions as an automatic API proxy generator, allowing developers to define endpoints as interfaces to eliminate manual HTTP request boilerplate. The library is designed for compatibility with ahead-of-time compilation and trimmed binaries, utilizing build-time source generation to ensure support for native AoT deployments. The project covers a broad range of API integration capabilities, including attribute-driven request composition, automatic JSON deserialization, and request header managem

Moya is a network abstraction layer for Swift that provides a structured framework for defining and executing REST API requests. It functions as a type-safe API client that decouples network endpoint definitions from the underlying implementation details to prevent configuration errors and URL typos. The project distinguishes itself by using protocol-based endpoint definitions and a provider-coordinated execution model. It includes a system for mapping network responses to strongly typed objects and features a dedicated tool for generating type-safe network interface files from external REST

Elysia is a high-performance TypeScript web framework designed for building type-safe backend services. It provides a modular, plugin-based architecture that allows developers to compose server logic, middleware, and validation schemas into scalable application instances. By leveraging native web standards, the framework ensures portability across diverse JavaScript runtimes, including Node.js, Deno, and various edge computing environments. The framework distinguishes itself through its focus on end-to-end type safety, automatically synchronizing request and response definitions between the s

Baileys is a TypeScript API client library used to interact with the WhatsApp Web API via WebSockets without requiring a browser. It functions as a real-time communication tool that handles bidirectional data exchange and event-based socket connections. The project includes a dedicated toolkit for managing WhatsApp Business profiles and product catalogs, alongside a session manager that authenticates accounts using QR codes or pairing codes and persists session state to disk. Its capabilities cover a wide range of messaging functions, including multi-type message transmission, chat history s

Django Ninja is a high-performance framework for building type-safe REST APIs using Django. It functions as an OpenAPI API framework and a type-safe wrapper that utilizes Python type hints to handle request validation and response serialization. The project distinguishes itself by integrating Pydantic-based data modeling to convert JSON inputs into strongly typed Python objects. It automatically generates OpenAPI schemas and interactive documentation pages directly from defined endpoint signatures. The framework supports asynchronous request processing to handle concurrent tasks. It employs

NSwag is a toolchain for the .NET ecosystem designed to automate the generation of API documentation, server controllers, and typed client proxies from OpenAPI contracts. It functions as a contract-first API tool that enables the creation of server-side boilerplate and client libraries based on predefined specifications. The suite distinguishes itself through its ability to extract OpenAPI specifications from existing ASP.NET Core code via reflection and its capacity to generate type-safe TypeScript client proxies. It also provides an interactive documentation server that hosts and renders th

Goa is a design-first Go framework that generates server and client code, documentation, and request validation from a single declarative domain-specific language (DSL). At its core, it provides a Go DSL for defining API endpoints, data types, and error models, which compiles into fully functional HTTP and gRPC server stubs, client packages, and OpenAPI specifications. The framework distinguishes itself through its plugin-extensible code generation pipeline, allowing custom code generation steps, middleware, or transport layers to be added via plugins. It supports multiple transport protocols

Twirp is a Protocol Buffers RPC framework designed for implementing type-safe, distributed microservices communication over HTTP. It functions as a microservices communication framework and API code generator that produces strongly typed client stubs and server interfaces from schema definitions to eliminate manual network boilerplate. The framework ensures compatibility with existing web infrastructure by executing remote procedure calls over standard HTTP transport. It uses schema-driven contracts as a single source of truth to enable cross-language interoperability and decouple business lo

NSwag is an OpenAPI toolchain for .NET that provides a suite of generators for converting OpenAPI specifications and JSON schemas into clients, server stubs, and structured documentation. It enables the creation of type-safe client libraries and data transfer objects, as well as the generation of OpenAPI specifications by analyzing .NET controllers. The project supports contract-first API development by generating server controller stubs from specifications and offers dedicated TypeScript API integration to ensure type safety in frontend applications. It also provides tools for hosting intera

Encore is a distributed systems framework designed to unify backend development, infrastructure provisioning, and observability. It functions as an infrastructure-as-code platform that allows developers to define cloud resources, databases, and messaging topics directly within their application code. By analyzing these declarations at compile-time, the system automatically manages the deployment of cloud resources and security policies, ensuring parity between local development and production environments. The platform distinguishes itself through its integrated development experience, which

grpcui is a browser-based interactive web interface and API client for executing remote procedure calls to gRPC servers. It functions as an HTTP to gRPC gateway that translates JSON payloads into binary protobuf messages, allowing users to trigger network requests and inspect responses through a visual web interface. The tool provides schema browsing and discovery capabilities by querying server reflection or loading local protobuf descriptor files to identify available services and method signatures. It uses these definitions to automatically generate dynamic input forms for constructing req

Rest_rpc is a C++20 remote procedure call framework designed for building distributed services. It provides an asynchronous service interface that allows developers to expose local functions as network-accessible services, enabling remote clients to trigger tasks through automated serialization and communication protocols. The framework distinguishes itself by leveraging template metaprogramming to perform compile-time type introspection, which generates binary encoders and decoders without the need for runtime reflection. It further optimizes network throughput through zero-copy buffer manag

atproto is a decentralized social networking protocol implementation and a schema-driven API framework. It provides the networking and data standards required to build interoperable social networks where users control their own identity and data through a personal data server specification. The project distinguishes itself through a DID-based identity system for managing cryptographic keys and verifiable profiles, alongside a lexicon-based protocol definition that uses versioned schemas to ensure consistency across network services. It utilizes Merkle Search Trees for verifiable data storage,

SignalR is a .NET real-time web framework designed to push content from a server to connected browser and non-browser clients. It provides a server-to-client push framework and a remote procedure call system that enables bidirectional communication over persistent connections. The library utilizes WebSockets to establish full-duplex connections and includes a transport-layer abstraction to manage different network protocols. It employs client-side connection negotiation to determine the best available communication protocol during the initial handshake. The system manages persistent connecti

Swashbuckle.AspNetCore is an API specification tool and documentation generator for ASP.NET Core. It extracts metadata from source code and models to produce standardized OpenAPI specifications and interactive browser interfaces for exploring and testing web APIs. The project integrates a middleware component to serve these specifications and a Swagger UI for interactive API testing directly from a running application. It also provides a command-line exporter to extract specification files from application assemblies for use in CI/CD pipelines. The tool covers a wide range of capabilities in

Ring is a Clojure HTTP web library that represents requests and responses as immutable data structures. It provides a functional framework for web development, treating HTTP traffic as standardized maps to decouple application logic from specific server implementations. The project features a middleware framework for composing reusable functional layers to handle cross-cutting concerns such as authentication and logging. It includes a server adapter system that translates raw traffic into request maps, as well as a dedicated integration layer for upgrading standard HTTP connections to bidirec

This project is a comprehensive sample library and implementation guide for ASP.NET Core. It provides a collection of practical examples and projects that demonstrate how to build web applications, RESTful APIs, and high-performance services. The repository focuses on a variety of architectural patterns, including the development of Minimal APIs, contract-first gRPC services, and real-time communication using WebSockets and Server-Sent Events. It includes detailed implementations for user identity and security, such as token-based authentication and CSRF protection. The codebase covers a bro

Hono is a lightweight web framework built on Web Standard APIs that executes across JavaScript runtimes including Cloudflare Workers, Deno, Bun, and Node.js.

This project is a comprehensive reference collection of practical implementation examples and patterns for building applications with Spring Boot. It serves as a Java web application template and a showcase for developing functional web services featuring REST endpoints, template engines, and global exception handling. The repository distinguishes itself by providing detailed demonstrations of enterprise-grade features, including distributed locking, task scheduling, and asynchronous message exchange using brokers like RabbitMQ. It also includes reference implementations for automated API doc

ASP.NET Core is a unified, cross-platform framework designed for building scalable web applications and services. It provides a comprehensive environment for constructing server-side rendered applications, real-time communication services, and interactive web components using C# and .NET. The framework distinguishes itself through a modular architecture that centers on a built-in dependency injection container, which manages service lifecycles and component modularity to improve testability. It utilizes a middleware pipeline to process requests and employs policy-based authorization to secure

This project is an educational framework designed to teach the fundamentals of building core distributed systems and web services from scratch in Go. It provides a collection of modular implementations that demonstrate how to construct essential infrastructure components, including web servers, remote procedure call systems, distributed caches, and database abstraction layers. The framework distinguishes itself by focusing on the internal mechanics of these systems rather than providing a high-level abstraction for production use. It covers the implementation of complex architectural patterns

mcp-context-forge is a Model Context Protocol federation gateway that unifies diverse AI tool servers and APIs into a single consistent interface for discovery and execution. It acts as a centralized proxy that aggregates multiple servers and APIs, allowing AI agents to access and invoke a unified set of tools, prompts, and resources. The project distinguishes itself through a multi-protocol translation bridge that converts communication between standard I/O, SSE, gRPC, and REST to enable interoperability between disparate tool servers. It includes a comprehensive LLM evaluation framework for