Find the best open-source alternatives

A free, open-source web application security scanner for finding vulnerabilities during development and testing.

A simple, fast, accurate single-header microbenchmarking library for C++11/14/17/20.

A lightweight finite state machine library for GameMaker, designed as an alternative to SnowState with different design trade-offs.

A free, customizable macOS system monitor that displays CPU, memory, network, temperature, and fan stats in the menu bar.

A simple, fast, and powerful Earley parser toolkit for JavaScript that handles any BNF grammar.

A Common Lisp lexical analyzer generator that defines a domain-specific language within your Lisp program, eliminating the need for external tools.

A Swift framework for building real-time graphics pipelines on iOS, macOS, and tvOS using Metal.

An open-source integrated development environment (IDE) and application framework for Java, PHP, and other languages.

A cross-platform desktop GUI client for interacting with gRPC services, supporting all streaming types and automatic proto parsing.

An experimental Sitecore data provider that loads serialized items directly from disk, eliminating sync tools.

Neovim plugin implementing Urtext, a markup language for Python scriptable-notebooks within a text editor.

An extremely fast Python package and project manager written in Rust, replacing multiple existing tools.

Open source Terraform module registry with UI, Git integration, security alerts, cost estimation, and deep analysis.

A small build system focused on speed, designed to compile software quickly.

A self-hosted, Quora-like web application for private Q&A communities, built with Go.

An advanced, open-source object-relational database management system supporting SQL standards, transactions, and extensibility.

A standalone GUI for visualizing and analyzing Linux perf data, featuring flame graphs, timeline filtering, and off-CPU profiling.

A single-file TLS 1.0-1.3 and DTLS implementation in C, using libtomcrypt for cryptography.

A Python library for programming 2D/3D games, graphics, and sound synthesizers interactively in Jupyter notebooks.

A cross-platform desktop application for editing and previewing Markdown files in real-time.

Python bindings for the Mapnik C++ library, enabling programmatic map rendering and geospatial visualization.

A very fast and accurate code counter with complexity calculations, COCOMO/LOCOMO estimates, and unique line metrics written in pure Go.

A Rails gem for managing tags using PostgreSQL array columns with efficient querying and tag cloud strategies.

A free, fully featured model rocket simulator for designing and simulating rockets before building and flying them.

A MicroPython menu implementation for LCD displays with submenus, actions, and callbacks.

A property-based testing library for Scala with advanced generators, flexible configuration, and full Scala.js/scala-native support.

A computing-focused community platform for link aggregation and discussion, built with Ruby on Rails.

A Godot plugin for procedural audio and adaptive music, enabling complex soundscapes with minimal code.

A Node.js library that turns MongoDB collections into message queues and event logs without additional infrastructure.

An open-source CLI scanner that finds AWS attack chains and provides copy-paste remediation with AWS CLI and Terraform.

An open-source API for metering and usage-based billing, supporting hybrid pricing models and self-hosting.

A C++20 single-header, macro-free μ(micro)/unit testing framework focused on fast compilation and modern C++ features.

Effects-based direct-style parallel IO stack for OCaml 5, enabling concurrent file, network, and CPU operations with a secure, cross-platform API.

A flexible static site generator for blogs written in Common Lisp, using Git for storage and supporting plugins.

A tiny, high-performance JavaScript library for color parsing, manipulation, and conversion with a plugin-based architecture.

A lightweight React internationalization library based on the ICU standard, optimized for bundle size and performance.