Open-source alternatives to Fastapi

Hug is a Python API framework used for building web services by mapping functions to HTTP endpoints via decorators and type annotations. It functions as a type-based validator that automatically converts and validates incoming request data based on Python type hints and serves as a WSGI-compliant web framework for deployment on production servers. The project is distinguished by its ability to automatically generate API specifications and user-facing documentation derived from function signatures. It further extends the utility of internal logic by exposing functions as terminal commands thro

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

Actix Web is an asynchronous web framework designed for building high-performance network services. It provides a foundation for processing concurrent requests through a non-blocking execution model, utilizing an actor-based concurrency system to manage lightweight processes and message passing. The framework includes a low-level networking layer that handles the parsing and serialization of HTTP traffic according to standard specifications. The framework distinguishes itself through a type-safe routing engine that enforces strict data types at compile time, ensuring that request parameters a

This project serves as a comprehensive resource hub and curated directory for the FastAPI web framework ecosystem. It provides developers with a centralized collection of community-vetted libraries, tools, and best practices designed to support the development, testing, and deployment of scalable web services using modern Python. The repository distinguishes itself by aggregating resources that address the full lifecycle of high-performance API development. It covers essential capabilities including project scaffolding, database integration, and the implementation of real-time communication p

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

Sanic is an asynchronous Python web framework designed for building high-performance APIs and services. It operates as a production-ready ASGI web server, utilizing a non-blocking event loop to handle concurrent requests and maximize throughput. The framework is built to support scalable architectures, offering built-in worker process management to distribute traffic across available CPU cores. What distinguishes Sanic is its focus on modularity and developer-centric tooling. It features a blueprint-based system for organizing complex applications into pluggable components, alongside a robust

Quart is an asynchronous Python web framework that implements the ASGI specification. It is used to build high-performance HTTP and WebSocket services, JSON REST APIs, and web applications using async and await syntax for non-blocking request handling. The framework supports persistent bidirectional communication via WebSocket API servers and enables the proactive delivery of assets through HTTP server push. It also includes a template engine for rendering dynamic HTML web pages and supports incremental request and response streaming to manage large payloads. General capabilities cover reque

Eve is a REST API framework that maps database collections to web resources through declarative configuration files. It functions as a database-to-API mapper, automatically exposing data as RESTful endpoints with built-in support for CRUD operations and schema-based request validation. The project distinguishes itself through a HATEOAS API engine that generates hypermedia links and resource schemas for dynamic client discovery. It also includes an automated Swagger documentation generator that produces interactive specifications for client SDK generation and testing. The framework provides a

API Platform is a headless content management system engine and framework used to build REST and GraphQL APIs. It utilizes schema-driven generation to automatically produce web endpoints based on predefined data model definitions. The platform focuses on semantic data modeling, using structured classes and ontologies to ensure information is organized for search engines and semantic web tools. It provides an automated OpenAPI specification generator and a declarative system for creating administration dashboards to manage data records without custom frontend code. The system includes capabil

Sanic is a Python ASGI web framework and asynchronous HTTP server. It is designed to build high-performance web applications and servers that handle concurrent requests using non-blocking logic. The framework implements the Asynchronous Server Gateway Interface standard, allowing applications to be deployed across various ASGI-compatible servers. It utilizes an asyncio-based event loop and integrates a Cython-based runtime wrapper around libuv to manage I/O operations. The system manages traffic through route-based request dispatching and a middleware-based request pipeline. These components

Drogon is a high-performance C++ HTTP web framework and asynchronous web server designed for building web applications and REST APIs. It utilizes an event-driven, non-blocking architecture to handle concurrent HTTP and WebSocket connections, and it implements a model-view-controller structure to separate business logic from presentation. The framework includes an integrated C++ object-relational mapping system and database client for performing asynchronous operations with relational databases and Redis key-value stores. It supports real-time, full-duplex communication via WebSockets and prov

Restify is a Node.js web framework designed for building scalable RESTful web services and APIs. It provides a server-side environment for creating HTTP network services with integrated routing and request handling. The framework utilizes a middleware-based architecture to process incoming requests and manage responses. This approach supports the construction of web interfaces that follow standard architectural principles to deliver data to clients. The system covers a broad range of backend engineering capabilities, including route-based request dispatching, schema-based request validation,

Japronto is an asynchronous web framework and Python HTTP server toolkit. It functions as a multi-worker HTTP server and request router, utilizing non-blocking asynchronous handlers to manage high concurrency and throughput. The project implements a master-multiworker forking model to distribute network traffic across multiple CPU cores. It incorporates a fast event loop and a specialized C-extension for high-speed HTTP request parsing, while supporting request pipelining over single TCP connections. The framework covers a broad range of request handling capabilities, including URL pattern r

routing-controllers is a declarative API router and web framework controller for TypeScript. It provides a system for defining HTTP routes and request handling logic using class-based decorators and metadata to organize API endpoints into a structured architecture. The project utilizes adapter-based server integration to decouple routing logic from the underlying web framework, providing specific integrations for Express and Koa. It features a reflection-based type transformation system that validates and transforms incoming request parameters into typed class instances. The capability surfa

Robyn is a high-performance asynchronous web framework and server for Python that utilizes a Rust-powered runtime to execute code. It functions as an asynchronous Python web server designed to handle many concurrent requests efficiently through a multithreaded execution model. The project includes specialized capabilities for AI agent request routing, managing communication between agents and external tools. It also serves as a WebSocket communication server, maintaining persistent bidirectional channels for real-time data exchange. The framework covers a broad range of web infrastructure, i

Play is a full-stack reactive web framework for Java and Scala. It provides a comprehensive development platform for building scalable web applications and RESTful APIs using a stateless and non-blocking architecture designed for high concurrency. The framework emphasizes high-velocity development through dynamic code reloading, which allows developers to update applications and verify changes without performing a full restart. Its capability surface covers the construction of JSON-based web endpoints, server-side logic for the JVM, and the implementation of scalable web architectures.

Grape is a RESTful web service framework for Ruby designed for building structured APIs. It provides a declarative syntax for routing and parameter validation, allowing developers to map HTTP verbs to logic through a domain specific language. The framework is distinguished by its built-in support for service versioning, which can be managed via URL paths, custom headers, or request parameters. It also features a modular architecture that allows large services to be constructed by nesting smaller API definitions. The project covers comprehensive API lifecycle capabilities, including schema-dr

Oatpp is a high-performance C++ web framework and API development kit used for building REST APIs and web services. It functions as an asynchronous HTTP server that utilizes coroutines to handle thousands of simultaneous connections without blocking threads. The toolkit includes a native C++ object-relational mapping layer for executing SQL queries and transforming database results into data objects. It also provides a WebSocket communication library for establishing full-duplex channels to support real-time data streaming and live media. The framework covers a broad range of capabilities, i

Starlette is a lightweight ASGI web framework and asynchronous HTTP toolkit used to build high-performance HTTP and WebSocket services. It functions as a WebSocket server framework and a collection of ASGI middleware components for managing network requests through non-blocking asynchronous logic. The framework provides tools for real-time communication via persistent bidirectional channels and infrastructure for high-performance APIs. It includes specialized capabilities for response compression, incremental data streaming, and the execution of non-blocking background tasks after a response

Pyramid is a Python web framework and WSGI toolkit designed for building web applications. It functions as a URL routing engine that maps incoming HTTP requests to specific view callables using both pattern-based routing and hierarchical resource tree traversal. The framework is distinguished by its hybrid dispatch system, allowing developers to combine regular expression URL matching with the ability to resolve requests by navigating a tree of nested objects. It implements a flexible component architecture that supports application registry management, deferred configuration execution, and t

FastHTML is a full-stack Python web framework designed for building interactive web applications using pure Python. It functions as an HTMX integration framework and a Python HTML domain-specific language, allowing developers to generate HTML structures using native objects and functions instead of external templating files. The framework is distinguished by its native support for real-time bidirectional communication via WebSockets and Server-Sent Events, enabling server-side updates to be pushed to the browser without full page reloads. It further integrates identity management through OAut

Crow is a minimalist C++ micro web framework designed for building fast web servers and REST APIs. It provides a lightweight toolkit for web development in C++, offering core routing and request handling capabilities. The framework includes a built-in JSON parser for converting strings into structured data and an HTML template engine for generating dynamic web pages on the server. It also functions as a WebSocket server library to enable bidirectional, real-time communication between servers and web clients. Additional capabilities include a middleware-based request pipeline for executing sh

Vibora is an asynchronous Python web framework and built-in HTTP server designed for building high-performance web applications. It utilizes an asynchronous event loop and coroutines to process network requests and serve responses without requiring external server wrappers. The project features a high-performance asynchronous schema validator for request integrity, a non-blocking template engine with support for hot-reloading, and a WebSocket communication server for bidirectional real-time data exchange. The framework covers a broad range of capabilities, including modular route management

Iris is a high-performance web framework and API toolkit for the Go programming language. It provides the infrastructure necessary to build HTTP/2 web applications, REST APIs, and MVC-based websites. The project distinguishes itself through a flexible architectural model that supports multiple isolated application instances within a single process and allows for binary-embedded asset loading to eliminate external filesystem dependencies. It features dynamic router hot-reloading and a pluggable view engine for rendering dynamic HTML content. The framework covers a broad range of capabilities,

userver is a comprehensive C++ backend application platform and asynchronous framework designed for building scalable microservices. It provides a high-performance execution environment for deploying services that communicate via gRPC and HTTP using a middleware-based request pipeline. The platform distinguishes itself through a distributed service orchestration toolset that manages shared state, distributed locking, and dynamic configuration updates without requiring process restarts. It utilizes a coroutine-based asynchronous execution model and event-loop network I/O to handle high-concurr

Fiber is a high-performance web framework designed for building scalable HTTP services with minimal memory overhead. It provides a comprehensive runtime environment for managing the full request lifecycle, utilizing an optimized radix tree for high-speed route matching and an object pooling system to reduce garbage collection pressure during traffic processing. The framework distinguishes itself through its multi-process architecture, which supports prefork socket reuse to distribute incoming traffic across all available CPU cores. It offers a modular approach to application development, feat

go-restful is a framework for building RESTful web services in Go. It functions as a toolkit for managing API endpoints, providing a request router that maps incoming HTTP requests to handler functions using path parameters and custom URL patterns. The framework includes a data conversion layer that transforms Go structures into JSON or XML formats for request and response bodies. It also provides a system for organizing related web services into containers to manage endpoint prefixing and shared configuration. The project covers request lifecycle management through middleware filters for va