OpenAPI Client Code Generators

Swagger Codegen is a template-driven engine and multi-language toolkit used to generate API client SDKs, server stubs, and human-readable documentation from OpenAPI specifications. It translates these specifications into functional libraries and boilerplate routing code across various target programming languages. The tool utilizes a pluggable generator module system and an integrated template engine, allowing for the customization of generated source code and the creation of new language-specific generators. It supports flexible specification sourcing via local files, remote HTTP endpoints,

This project is a command-line tool and template-based scaffolding engine that transforms API interface specifications into functional client libraries and server stubs. By automating the creation of type-safe SDKs and boilerplate code, it bridges the gap between service definitions and implementation, allowing developers to maintain synchronized codebases across many programming languages. The tool distinguishes itself through a portable execution model that utilizes containerized build isolation to ensure identical output regardless of the host environment. It features a modular, plugin-bas

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

go-swagger is a toolkit for working with Swagger/OpenAPI 2.0 specifications in Go. It generates server, client, and CLI code from a specification document, and can also produce a specification by scanning annotated Go source code. The project includes a static validation engine that checks documents against the schema and project-specific rules, and a specification transformation pipeline that resolves, flattens, and merges documents. The toolkit generates both client and server code from the same specification, ensuring consistency in request and response handling. It also produces a command

openapi-ts is a tool and orchestrator used to convert OpenAPI specifications into type-safe TypeScript SDKs and HTTP client implementations. It automatically generates typed interfaces and request functions from API definitions to ensure consistency between the server and the client. The project employs a transport-agnostic client interface, decoupling high-level API calls from the underlying network library. It uses a plugin-based generation pipeline and a custom plugin architecture to allow for the customization of output types and validation schemas. The system provides capabilities for n

oapi-codegen is a suite of generators that converts OpenAPI 3 specifications into type-safe Go client libraries, server boilerplate, and data models. It provides tools for producing production-ready HTTP clients and server-side interfaces to ensure that Go implementations remain compliant with defined API contracts. The tool supports server generation across various web frameworks and allows for extensive customization via template overrides, specification overlays, and custom type definition mappings. It handles complex API requirements through external reference resolution to organize code

The Swift OpenAPI Generator is a build-time tool that produces type-safe Swift client and server code directly from OpenAPI specification documents. By integrating with build systems through native plugins, it automates the creation of strongly-typed interfaces and protocol stubs that map network operations to native methods, ensuring that application code remains strictly consistent with defined data schemas. The project distinguishes itself through a protocol-oriented architecture that decouples business logic from specific transport implementations. It utilizes a pluggable transport layer

OpenAPI Generator CLI is a command-line utility designed to automate the creation of API artifacts from specification files. It functions as a tool for generating client libraries, server stubs, and documentation, enabling developers to produce consistent boilerplate code and reference materials across various programming languages. The project provides a wrapper that manages the lifecycle of a Java-based execution engine, which performs the actual code synthesis using logic-less templates. To ensure reproducible results and avoid dependency conflicts on the host system, the tool supports ver

This project is a command-line tool that automates the creation of type-safe TypeScript HTTP clients directly from OpenAPI specifications. By transforming service definitions into structured source code, it ensures end-to-end type synchronization and enforces runtime data integrity across network boundaries. The generator distinguishes itself by mapping OpenAPI data structures into Zod validation schemas, allowing for consistent schema-driven type mapping and response validation. It supports deduplicated source synthesis to minimize redundancy in the generated output and provides template cus

The Kaggle API command line interface is a suite of utilities for managing datasets, machine learning models, and competition entries from a terminal. It functions as a command line wrapper that translates user input into API calls to control remote cloud resources. The project differentiates itself by providing specialized tools for automating the execution of notebook kernels and managing the lifecycle of machine learning models, including version iteration and performance tracking. It also includes a utility for executing evaluation tasks against large language models and downloading the r

This project is a comprehensive microservices development framework designed to build scalable, resilient backend systems. It provides a production-ready runtime that integrates stability patterns directly into the service architecture, ensuring consistent performance and reliability for both web and remote procedure call services even under heavy traffic conditions. The framework centers on an interface-first development model, utilizing a domain-specific language to define service contracts that serve as the single source of truth. This approach powers an extensive code generation ecosystem

Bruno is a local-first API client designed for building, testing, and managing network requests across a wide range of protocols. By storing all collections and configurations as plain-text files directly on the local filesystem, it enables native version control and offline access, ensuring that project data remains under user control without requiring cloud synchronization. The platform distinguishes itself through a declarative approach to API management, utilizing a domain-specific language to define request parameters and metadata. This architecture supports a robust testing environment