Free & open-source tools

General-purpose language with the world's largest scientific & AI ecosystem.

GNU Compiler Collection — the reference open-source C and C++ compiler.

Modern C, C++, Objective-C compiler and toolchain infrastructure.

Cross-platform runtime + SDK for C#, F# and ASP.NET.

Free Java Development Kit used by every major distribution.

Fast statically-typed language by Google with batteries-included tooling.

Memory-safe systems language with the Cargo package manager.

JavaScript & TypeScript runtime for servers, CLIs and tools.

Modern JVM language, official for Android development.

Elegant dynamic language behind Rails.

Apple's modern systems language — server & iOS friendly.

Language + UI toolkit for cross-platform mobile, web & desktop.

Powers WordPress, Laravel and most of the web's CMSes.

Tiny embeddable scripting language — game scripting & Neovim.

Pure functional language with a powerful type system.

Concurrent, fault-tolerant language on the BEAM VM.

Robust, optimal, low-level systems language with great C interop.

High-performance language for scientific computing & numerics.

Statistical computing & data visualization language.

The world's most popular editor. VSCodium is the telemetry-free build.

Hyper-extensible modal editor — Lua scripting, LSP built-in.

IntelliJ IDEA, PyCharm and Android Studio — free Community editions.

Veteran multi-language IDE, strongest for Java & embedded.

High-performance collaborative editor built in Rust.

Industry-grade schematic + PCB suite. Unlimited layers, 3D viewer, Gerbers.

Modern, simple cross-platform EDA — great starting point.

Integrated EDA package focused on a unified component database.

Mixed-signal circuit simulator — the open-source SPICE engine.

Schematic-driven analog/RF circuit simulator.

Friendly tool for breadboard, schematic and PCB — great for makers.

Parametric 3D modeler for mechanical engineering and product design.

Pro-grade 3D modeling, animation, sculpting, VFX, and rendering suite.

Programmer's CAD — describe solid models with code.

Computational fluid dynamics toolbox used in industry & research.

Cross-platform IDE & build system for 1000+ embedded boards.

Beginner-friendly C/C++ environment for microcontrollers.

Espressif's official framework for ESP32 / ESP8266 development.

Scalable real-time OS for resource-constrained devices.

The de-facto research framework for deep learning.

End-to-end ML platform from Google.

Classical ML algorithms — clean Python API.

Thousands of pre-trained models for NLP, vision and audio.

Run LLMs (Llama, Mistral, Qwen…) locally with one command.

The most advanced open-source relational database.

Zero-config embedded SQL database — used everywhere.

In-memory data store for cache, queues and pub/sub.

In-process analytical SQL engine — Pandas/Parquet friendly.

Distributed version control — the backbone of modern dev.

Container runtimes for building reproducible environments.

Production-grade container orchestration.

Self-hosted Git service — lightweight GitHub alternative.

Industry-standard network protocol analyzer.

Powerful port scanner & network discovery tool.

Open-source web app security scanner.

Penetration testing framework — community edition.

High-performance network IDS / IPS / NSM engine.

Open-source firewall & router platforms based on FreeBSD.

Fast, modern, audited VPN protocol — in-kernel on Linux.

Secrets management, encryption-as-a-service & PKI.

Declarative UI library by Meta — the most-used frontend framework.

Approachable, performant, versatile frontend framework.

Compile-time framework producing tiny, fast JS bundles.

Content-first framework with island architecture & zero-JS by default.

Lightning-fast dev server and build tool for modern web apps.

Utility-first CSS framework for rapid UI development.

Minimal & high-performance Node.js HTTP server frameworks.

Modern Python framework for typed, async REST & GraphQL APIs.

Batteries-included Python web framework — ORM, admin, auth.

Production-grade Java framework for microservices & web APIs.

Opinionated Node.js framework for scalable server-side apps.

Instant GraphQL & REST APIs on Postgres + business logic.

Build natively-compiled mobile, web & desktop apps from one codebase.

Native iOS & Android apps with React.

Toolchain & framework that supercharges React Native projects.

Official IDE for native Android development (Kotlin/Java).

Hybrid mobile apps using web technologies.

Feature-packed 2D/3D engine with its own scripting language.

Data-driven game engine in Rust with an ECS architecture.

Fast 2D HTML5 game framework for the browser.

Free, cross-platform 2D game engine used in production.

Open-source XNA-style framework for C# game dev.

Unified analytics engine for large-scale data processing.

Distributed event streaming platform.

Workflow orchestration — author DAGs in Python.

Transform data in your warehouse using SQL + tests.

Easy, open analytics & BI dashboards.

Modern data exploration & visualization platform.

The standard Python data analysis library.

Infrastructure-as-code for any cloud provider.

Agentless configuration management & app deployment.

Metrics monitoring & time-series database — CNCF.

Observability dashboards for metrics, logs and traces.

S3-compatible high-performance object storage.

High-performance web servers & reverse proxies.

Robot Operating System — middleware for modern robotics.

Physics-based robot simulator integrated with ROS.

Open-source flight control for drones & VTOL.

Open-source home automation that puts local control first.

Lightweight MQTT broker — the IoT messaging standard.

Ethereum dev environment for smart contracts & dApps.

Blazing-fast Solidity toolkit written in Rust.

Contract-oriented language targeting the EVM.

Framework for Solana program development in Rust.

The kernel that powers most of the world's computing.

Advanced BSD operating system — networking & storage focused.

Generic & open-source machine emulator and virtualizer.

Source-level debuggers for compiled languages.

Reverse-engineering & binary analysis suite by the NSA.

Powerful raster image editor — the open Photoshop.

Pro digital painting app loved by illustrators.

Vector graphics editor for SVG and print.

Pro non-linear video editor & color grading suite.

Full-featured open-source non-linear video editor.

Multi-track audio recorder and editor.

Free streaming & screen recording software used by pros.

Full office suite — Writer, Calc, Impress, Draw, Base.

Local-first Markdown knowledge base with backlinks.

Open-source outliner & PKM — Roam-style graph notes.

Encrypted, sync-friendly open-source notebook.

Self-hosted Drive, Calendar, Office, Chat — full suite.