API tooling

Tyk is an open-source API gateway written in Go that routes, secures, and monitors network traffic across REST, GraphQL, TCP, and gRPC protocols. It functions as a multi-protocol proxy designed to deliver requests to backend services while managing the end-to-end API lifecycle. The system distinguishes itself through a plugin-based architecture that allows for the injection of custom logic into the request and response middleware chain. It also features native Kubernetes integration, operating as an ingress controller that uses operators and custom resource definitions to deploy security policies and orchestrate API routing. The gateway covers a broad range of management capabilities, including standardized authentication via tokens and certificates, granular access control, and network restrictions. It provides tools for traffic rate limiting and quotas to protect backend services, along with usage analytics and event-driven webhooks for external notifications. Configuration is managed through a dedicated command line tool that synchronizes system settings with version control systems across distributed nodes.

Kong is a high-performance API gateway and service connectivity platform designed to manage, secure, and monitor traffic across distributed microservices and hybrid cloud environments. It functions as a centralized control plane for service governance, providing essential traffic routing, load balancing, and request transformation capabilities to ensure consistent policy enforcement across all service endpoints. The platform distinguishes itself through a modular plugin architecture and a declarative configuration engine that allows infrastructure behavior to be defined via version-controlled files. This approach enables consistent, repeatable deployments and allows for the injection of custom logic directly into the request processing pipeline. Furthermore, it provides specialized support for service mesh communication, enabling secure, encrypted, and observable inter-service connectivity through lightweight sidecar proxies that integrate with standard container orchestration workflows. Beyond core routing, the platform encompasses a broad range of operational capabilities including API performance monitoring, usage metering for billing and resource governance, and event stream security. It also provides governance for AI-native applications and administrative controls such as role-based access management and audit logging to maintain operational standards across diverse environments. The platform supports development workflows through integrated tools for service interface mocking and the publication of interactive documentation. It is designed for deployment within containerized clusters, utilizing native controllers to automate traffic management and infrastructure provisioning.

Insomnia is a cross-platform API development environment that integrates a request debugger, schema design tools, a mocking server, and a test automation framework. It provides a unified workspace for sending requests and analyzing responses across REST, GraphQL, gRPC, and WebSocket protocols. The platform enables the design and preview of API specifications through a visual editor and allows for the simulation of backend behavior using mocking tools. It supports organizing and synchronizing API collections via local storage, cloud synchronization, or Git. The suite includes a command-line interface for executing linting and testing tasks within continuous integration pipelines. It also features a plugin system for third-party extensions and a secure system for storing environment variables locally to protect sensitive credentials.

FastAPI is a high-performance Python web framework designed for building REST APIs. It operates as an ASGI web framework, providing a system to create structured HTTP endpoints that automatically serialize data and validate request parameters. The framework utilizes Python type hints to drive data validation and serialization, automatically generating machine-readable OpenAPI and JSON Schema specifications. This process enables the automatic creation of interactive, browser-based API documentation where endpoints can be tested directly. The project includes a dependency injection system for managing shared logic and supports asynchronous request handling and WebSocket communication for real-time data exchange. It also provides tools for API endpoint security through authentication and authorization standards. Local development is supported via a server with hot reloading, and the framework includes utilities for automated cloud deployment.

Yaak is a cross-platform desktop client and command-line utility designed for developing, testing, and debugging API endpoints. It supports multi-protocol request execution for REST, GraphQL, and gRPC services, providing a unified environment for managing network interactions, authentication credentials, and automated testing workflows. The tool distinguishes itself through a local-first architecture that stores all workspace configurations and request definitions directly on the filesystem. This design enables native integration with version control systems like Git, allowing teams to track changes to API specifications and share project structures. Furthermore, it utilizes operating system keychains for secure credential management and offers a modular plugin system to extend functionality through custom authentication methods, data importers, and template functions. Beyond manual testing, the platform facilitates complex workflow orchestration by supporting request chaining, dynamic payload generation, and scriptable test suites. These capabilities are exposed through a command-line interface, enabling the integration of automated endpoint validation and connectivity testing directly into continuous integration and deployment pipelines. The system also maintains persistent streaming runtimes to support real-time data flow and bidirectional communication with network services.

Hoppscotch is an open-source API development ecosystem designed for building, testing, and debugging REST, GraphQL, and real-time APIs. It provides a unified platform that functions across web browsers, desktop applications, and command-line interfaces, allowing developers to manage the entire API lifecycle from a single environment. The platform distinguishes itself through a highly interactive, command-driven interface that utilizes a global spotlight palette and keyboard shortcuts to streamline complex workflows. It supports advanced request manipulation and validation by executing JavaScript-based scripts and assertions within a sandboxed runtime. Furthermore, it integrates AI-assisted tools to automate the generation of request payloads, test scripts, and documentation, while maintaining compatibility with existing API definitions and collections from other formats. Beyond core testing capabilities, the project offers a collaborative workspace for teams to organize, share, and synchronize API collections and environment variables. It includes robust support for diverse authorization methods, proxy interception for network requests, and enterprise-grade features such as SCIM user provisioning and activity auditing. The software is available for self-hosted deployment via containerized architectures, ensuring consistent behavior across various production and development environments.

Apollo Server is a spec-compliant JavaScript implementation for building GraphQL APIs that resolve queries and mutations based on a defined schema. It functions as a Node.js framework that integrates GraphQL functionality into various web frameworks and serverless environments through middleware. The project provides a federated GraphQL gateway that aggregates multiple distributed subgraphs into a single unified entry point. It includes a built-in interactive API sandbox for testing operations at the server endpoint and a schema registry client to automate the synchronization of API definitions with a central registry. The server supports a schema-first execution pipeline with capabilities for multipart request processing for file uploads, response and parsed document caching, and request lifecycle plugins. Operational features include structured logging, health check management, usage metrics reporting, and security middleware to prevent request-based attacks.

graphql-engine is an automated GraphQL API engine that transforms database tables and relationships into a queryable GraphQL schema. It functions as a federation gateway and mapper, instantly generating APIs with built-in filtering, pagination, and mutations from existing databases and remote schemas. The project distinguishes itself through a fine-grained access control layer that enforces row-level and field-level permissions. It further provides a real-time data subscription server that converts standard queries into live streams and a system for triggering event-driven webhooks and notifications in response to database changes. The platform covers a broad range of capabilities including remote schema federation for merging disparate data sources, a REST API gateway for exposing saved queries, and support for spatial and hierarchical data querying. It also includes tools for schema migration management and a visual administrative interface for database configuration. The system can be deployed via containerized orchestration using Docker Compose or Kubernetes.

Graphene is a library and framework for building type-safe GraphQL APIs and schemas using Python objects and resolvers. It provides a system for mapping internal data models to typed GraphQL schemas, enabling the creation of servers that process queries and execute resolvers to return structured data. The project includes a full implementation of the Relay specification, providing standardized patterns for global object identification and cursor-based pagination. It utilizes a class-based approach to schema definition and supports interface-based type inheritance. The framework covers a broad range of API development capabilities, including the management of data mutations, custom scalar mapping, and the integration of multiple backend data sources into a unified data layer.

SchemaStore is a centralized JSON schema registry and configuration validation service. It serves as a searchable catalog of standardized JSON definitions used to verify that configuration files adhere to predefined structural rules and data types. The project functions as an autocomplete provider, suggesting available keys and valid values for configuration files during the editing process. It employs a remote directory of schemas indexed by file path and pattern to provide a single source of truth for validation and autocompletion in text editors. The system covers automated configuration verification and centralized schema management. This includes the ability to retrieve schemas via a standard protocol and map specific file names or directory structures to corresponding schema definitions.

Insomnia is a desktop application designed for the design, testing, and debugging of network requests. It serves as a comprehensive environment for managing the API lifecycle, allowing users to draft interface specifications, simulate endpoints, and execute automated testing workflows within continuous integration pipelines. The platform distinguishes itself through a modular, plugin-based architecture that enables the integration of custom scripts and external tools. It supports complex development needs by providing a local-first data persistence model, environment-variable substitution for managing different deployment stages, and request-response interception middleware for real-time validation and authentication. Beyond core request handling, the application facilitates team collaboration by synchronizing configurations and security credentials across environments. It includes tools for managing role-based access and identity, ensuring that sensitive API resources remain organized and secure throughout the development process.

Type-graphql is a toolkit and framework for creating type-safe GraphQL APIs. It functions as a schema generator and resolver library that uses TypeScript classes and decorators as the primary source of truth for data structures and query logic. The project enables the definition of GraphQL schemas and resolvers through typed classes rather than manual schema definition language. This approach ensures that TypeScript types automatically align with the GraphQL schema to prevent runtime errors. The framework provides capabilities for API implementation, including input data validation and access control through guards. It further supports resolver organization via dependency injection and controller classes.

yapi is an API management platform designed to coordinate the development of RESTful APIs between frontend, backend, and quality assurance teams. It functions as a centralized system for documenting interface specifications, simulating server responses, and validating requests through a built-in testing client. The platform features an API code generator that transforms interface specifications into typed request functions and data models across multiple programming languages. It also includes a mock server capable of generating synthetic responses using schema-based generators and rule-based simulation. The system provides tools for interface documentation, automated API testing with response assertions, and an importer for migrating definitions from formats such as Postman and Swagger. User access to these resources is managed via a flat-hierarchy permission system.

PostGraphile is an automated tool that converts a PostgreSQL database schema into a fully functional GraphQL API. It serves as a GraphQL execution engine and schema orchestrator, utilizing database schema introspection to retrieve strongly typed metadata directly from PostgreSQL. The project features a modular system for composing and standardizing GraphQL schemas through plugins, which manage naming conventions and connections. It includes a PostgreSQL query builder that constructs dynamic, SQL-injection-proof queries using tagged template literals. The system employs a declarative query planning engine to optimize request processing and reduce server load. Additionally, it provides a mechanism to export dynamically generated in-memory schemas into standalone JavaScript source code.

Higress is an AI API gateway and cloud-native traffic manager that functions as a Kubernetes ingress controller. It provides a centralized system for routing, securing, and optimizing traffic directed toward large language models, AI agents, and microservice architectures. The project distinguishes itself through deep AI orchestration, including the ability to host and manage Model Context Protocol servers that transform REST APIs into tools for AI agents. It features specialized AI infrastructure for model request proxying, protocol translation across multiple providers, and semantic-based caching to reduce token consumption and latency. Broad capabilities cover API lifecycle management and traffic control, including canary releases, load balancing, and rate limiting. The system includes a comprehensive security suite with WAF filtering, OIDC and OAuth2 identity integration, and automated TLS certificate management. Extensibility is provided via a WebAssembly-based plugin system that allows for hot-loading custom logic without interrupting traffic. The gateway can be deployed to Kubernetes or Docker and supports the Kubernetes Gateway API and Ingress standards.

Karate is an end-to-end testing framework and API test automation tool used to validate REST and SOAP APIs, drive browser interactions, and measure system performance. It functions as a unified solution for executing automated tests across both API backends and web frontends. The framework utilizes a custom domain specific language and Gherkin-style feature mapping to define requests and assertions. It includes an API mocking server to simulate backend responses, enabling development and integration testing without live dependencies. The tool covers a broad range of functional testing categories, including browser automation for UI component and workflow verification, as well as load testing to measure service stability under high-volume traffic. These capabilities are integrated into a single engine that handles both network requests and browser sequences.

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 where users can execute custom JavaScript-based validation scripts, perform complex assertions, and automate multi-step workflows. Its multi-protocol engine provides a unified interface for interacting with REST, GraphQL, gRPC, WebSocket, and SOAP services, while integrated environment-aware management allows for seamless switching between different deployment configurations. Beyond core request execution, the tool includes a comprehensive suite of utilities for documentation generation, secure authentication, and CI/CD integration. It supports advanced security workflows through various credential management protocols and secret providers, while its command-line interface facilitates parallel execution and data-driven testing within automated pipelines. Users can also leverage AI-driven automation to generate collections and test scripts, further streamlining the development process.

Type-graphql is a framework for building GraphQL servers that uses TypeScript classes as the single source of truth for schema definitions and types. It provides a schema generator and a resolver framework that allows developers to define queries and mutations using class-based controllers and decorators. The project focuses on a schema-first approach where TypeScript classes and metadata reflection are used to automatically derive GraphQL schemas. It incorporates a dependency injection container to manage the instantiation and lifecycle of resolver classes. The system includes a middleware layer for authorization and access control, utilizing guards to restrict access to specific resolvers. It also provides mechanisms for input validation to ensure API requests meet required type and format specifications.

Nhost is an open-source backend as a service that provides a managed PostgreSQL database, authentication, and file storage accessible through a unified GraphQL API. It functions as a backend infrastructure orchestrator, enabling the deployment and management of full-stack environments using containerization and command-line automation. The platform distinguishes itself by automating the transformation of relational database tables into a secure GraphQL API and providing an integrated identity provider that supports passwords, magic links, and OAuth. It also includes a serverless function runtime for executing isolated backend logic with automatic bundling and hot-reloading. The system covers a broad range of capabilities, including user identity and session management, S3-compatible object storage with dynamic image transformation, and role-based access control. It also provides tools for local development synchronization, virus scanning for file uploads, and integration protocols for connecting large language models to project data. The infrastructure can be managed via a command-line interface or self-hosted on private servers using containers.

Keystone is a GraphQL headless content management system and Node.js backend framework. It functions as a schema-driven data manager that automatically generates a GraphQL API and a React administrative dashboard based on a central data model configuration. The system uses an adapter-based database abstraction to decouple core logic from storage layers and a storage-provider abstraction for managing media assets via local or cloud drivers. It distinguishes itself through a component-based field rendering system and a hook-based middleware pipeline for data validation and automation. The framework covers a broad range of capabilities including role-based access control, user authentication, and the management of complex relational data models. It allows for system extension through a plugin-based architecture, custom GraphQL resolvers, and a customizable management interface.