Open-source alternatives to Gunicorn

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

RoadRunner is a high-performance application server and process manager designed to serve PHP applications using a persistent worker model. It eliminates bootload overhead and initialization time by keeping application processes alive between requests, acting as a protocol-agnostic proxy that routes traffic to a pool of supervised workers. The server is built with a plugin-based modular architecture, allowing it to be extended with custom Go plugins and compiled into tailored binaries. It distinguishes itself by providing a unified execution model for a wide array of communication protocols,

Fasthttp is a high-performance networking framework for Go, designed to maximize throughput and minimize memory overhead in demanding web applications. It functions as a specialized HTTP server and client library that prioritizes efficient resource management, allowing developers to build scalable services capable of handling massive concurrent traffic with minimal garbage collection pressure. The library distinguishes itself through a focus on zero-allocation processing and low-level optimization. It achieves this by recycling temporary request and response objects through managed pools and

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

NATS Server is a high-performance, lightweight messaging system designed for cloud-native applications, edge computing, and distributed microservices. It functions as a distributed publish-subscribe broker that routes messages using hierarchical, dot-separated subject strings, enabling decoupled communication between services without requiring centralized broker lookups. The system supports core messaging patterns including asynchronous publish-subscribe, request-reply, and load-balanced queue processing. The platform distinguishes itself through a decentralized architecture that eliminates t

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

Starlette is an asynchronous web framework and toolkit for building high-performance web services based on the ASGI specification. It serves as a lightweight foundation for creating web applications with a focus on asynchronous request and response handling. The framework provides specialized toolkits for managing persistent bidirectional WebSocket communication and an asynchronous HTTP server toolkit for routing and middleware. It distinguishes itself by offering a non-blocking background task queue that executes functions after a response has been sent to the client. The project covers a b

Vendure is a Node.js e-commerce engine and headless commerce framework built with NestJS and TypeScript. It serves as a multi-channel commerce platform that manages product catalogs, orders, and customers via a strongly typed GraphQL API. The platform is distinguished by its highly extensible architecture, featuring a customizable administrative dashboard where developers can inject custom React components and entity views. It supports multi-channel commerce, allowing the isolation of products, currencies, and regional catalogs from a single unified backend. The engine covers a broad range o

Hyper is a low-level networking library designed for building high-performance HTTP clients and servers. It provides a foundational toolkit for creating network services that leverage asynchronous execution and memory-safe data handling, supporting both HTTP/1 and HTTP/2 protocols. The library distinguishes itself through a protocol-agnostic architecture that separates transport logic from HTTP semantics. It utilizes a service-trait abstraction to decouple network logic from the underlying transport, enabling developers to inject custom middleware for request interception and response transfo

Pingora is a Rust-based framework for building high-performance network services, including HTTP reverse proxies, layer seven load balancers, and TLS termination proxies. It serves as an asynchronous network library designed to intercept and route HTTP, gRPC, and WebSocket traffic between clients and upstream backend servers. The project enables zero-downtime service updates by handing over listening sockets between processes during binary or configuration upgrades. It utilizes a programmable multi-phase pipeline to modify request and response bodies and headers, and it provides a pluggable T

Prefect is a workflow orchestration platform designed to define, schedule, and monitor complex data pipelines as Python code. It functions as a container-native engine that wraps individual tasks in isolated environments, ensuring consistent dependencies and resource allocation across diverse infrastructure. By utilizing a state-machine-based orchestration model, the system tracks execution progress through discrete transitions and persistent event logs to maintain reliable and observable task processing. The platform distinguishes itself through a decoupled worker-API architecture, which sep

Crawlee is a web scraping framework designed for building scalable, reliable, and distributed data extraction pipelines. It provides a unified interface for managing headless browser automation and lightweight HTTP requests, allowing developers to handle complex web navigation, dynamic content rendering, and large-scale data collection within a single, modular architecture. The project distinguishes itself through its resource-aware concurrency controller, which dynamically scales task execution based on real-time CPU and memory usage to prevent host machine exhaustion. It also features a rob

Excelize is a library for reading and writing spreadsheet files in the Office Open XML format. It provides a comprehensive suite of tools for programmatically creating, modifying, and analyzing workbooks, worksheets, and cell data, ensuring compatibility across various office software suites through structured XML serialization. The library distinguishes itself with a built-in formula calculation engine that evaluates complex mathematical and logical expressions directly against workbook data. It also features a memory-mapped streaming architecture, which allows for the efficient processing o

Dokploy is a self-hosted platform-as-a-service designed to simplify the deployment and management of containerized applications and databases. It provides a centralized control plane that decouples administrative management from application workloads, allowing users to oversee infrastructure across multiple server nodes through a unified web interface or a command-line tool. The platform distinguishes itself through an extensive library of pre-configured application templates, enabling the rapid deployment of databases, identity providers, and various productivity or development tools. It sup

Sidekick is a command-line tool that provisions bare VPS servers, transfers Docker images, manages secrets, and orchestrates zero-downtime deployments across single or multiple server instances. It handles the full deployment pipeline from a local machine, building container images locally and transferring them directly to the server without requiring a remote container registry. The tool distinguishes itself through an integrated approach to security and automation. It encrypts environment variables locally using SOPS and Age keys, then decrypts them on the server at deploy time for runtime

HHVM is a high-performance execution engine and runtime environment designed for the Hack language. It functions as a persistent web application server that processes incoming network traffic, while also providing command-line utilities for executing standalone scripts and performing automated tasks. The project distinguishes itself through a sophisticated execution model that utilizes just-in-time compilation to translate bytecode into optimized machine code. This process is supported by a static type analysis engine that enforces strict data constraints and identifies type inconsistencies b

This project is a Node.js process manager, runtime environment, and production deployment orchestrator. It provides the foundational system components required to run, monitor, and restart applications in the background to ensure continuous service availability. The system distinguishes itself through a built-in load balancer that distributes network traffic across multiple process instances to utilize all available CPU cores. It includes a real-time process monitor with a terminal-based dashboard for tracking server health, CPU and memory usage, and aggregated logs. The tool covers a broad

Passenger is a multitenant web server and dynamic process manager designed to host and manage web applications written in Ruby, Python, and Node.js. It functions as an application server that handles process and resource management, ensuring that multiple independent applications can run on a single server instance. The project distinguishes itself through a flexible deployment model, capable of operating as a self-contained standalone web server or as an integration module for existing high-performance external web servers. It employs a language-agnostic interface to provide polyglot hosting

Perfect is a server-side Swift framework designed for building high-performance web applications, REST APIs, and backend services. It provides an asynchronous HTTP server that handles web traffic through an event loop, alongside a web template engine for generating dynamic HTML pages. The project includes a WebSocket communication library for implementing bidirectional, real-time data exchange between clients and servers. It also provides a database connector to establish connections and exchange data between Swift applications and external database stores. The framework's capabilities cover

uWebSockets is a high-performance networking engine providing an HTTP web server and a WebSocket server framework. It implements a multi-threaded event loop architecture to deploy isolated application instances across multiple CPU cores and includes an SSL/TLS network layer for secure, encrypted communication. The project features a dedicated WebSocket pub/sub engine for distributing messages to specific groups of connected clients. It optimizes network throughput through syscall corking to reduce kernel overhead and employs payload compression to minimize data transfer sizes. The system cov

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

Cowboy is a high-performance HTTP server for Erlang and OTP. It is designed to handle web traffic with low memory usage and can be used as a standalone server or as an embedded networking library integrated directly into an existing application. The project implements modern transport protocols, including HTTP/3, QUIC, and WebTransport, to enable faster connections and bidirectional data streaming. It also functions as a real-time communication server supporting Server-Sent Events for pushing asynchronous updates to clients. Broad capabilities include path and content-type based request rout

Iron is a Rust web framework used for building concurrent web applications and APIs. It functions as a concurrent HTTP server and provides a stateless route dispatcher to map incoming URL paths and globs to specific handler functions. The project is centered around a middleware-based request pipeline, which allows the request-response cycle to be extended via plugins and modifiers. It utilizes a thread-safe state container to store shared application memory accessible across all concurrent handlers and middleware. The framework covers broad capability areas including dynamic API routing, sta

Warp is a Rust HTTP web framework designed for building high-performance web servers. It provides a system for managing request pipelines, implementing WebSocket servers for bidirectional communication, and serving static assets from the local filesystem. The framework is characterized by its use of type-safe request pipelines and routing. It utilizes a filter-based approach to extract and validate metadata from headers, query strings, and request bodies before they reach the application handler. Broad capability areas include HTTP API development, asynchronous task execution, and state-base

Hazelcast is a distributed data platform that combines an in-memory data grid with a stream processing engine to support real-time analytics and event-driven applications. It functions as a partitioned, distributed key-value store that replicates data across cluster nodes to provide low-latency access and high availability. The platform also serves as a distributed SQL query engine, allowing users to execute standard SQL statements against both in-memory datasets and external data sources. What distinguishes Hazelcast is its use of a distributed consensus subsystem to maintain strongly consis

Kitura is a server-side web framework for building HTTP services and web applications using the Swift programming language. It functions as an HTTP server that handles incoming requests, routes traffic, and serves responses. The framework serves as a Codable REST API framework, enabling the encoding and decoding of native Swift data types for web service communication. It also provides a FastCGI web interface to connect Swift applications to external web servers for improved scalability. The system includes capabilities for secure web communication through SSL/TLS network encryption, server-

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