Free
Ruff
Open SourceCLI Tools · Development Environment
An extremely fast Python linter and formatter, written in Rust.
pythonlintingformattingrust
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CLI Tools · Development Environment
An extremely fast Python linter and formatter, written in Rust.
Programming Languages
Official Rust website: documentation, book, crates and tooling.
Ecosystem · CSS Tools
The mature CSS extension language with variables and nesting.
Programming Languages
Official Scala language site with documentation and downloads.
Web Scraping · Data & Analytics
Python's industrial-strength crawling framework — spiders, middlewares, throttling and pipelines built in.
E2E & Browser · Testing
The long-standing browser automation suite with broad language support.
Cheatsheets & Learning · Git & Version Control
The SemVer specification for meaningful version numbers.
ORMs · Backend
Promise-based Node.js ORM for Postgres, MySQL, MariaDB and SQLite.
UI Libraries · Frontend
The shadcn/ui philosophy ported to Svelte: copy-paste components you own, built on Melt UI.
UI Libraries · Frontend
Copy-and-paste React components built on Radix and Tailwind.
Screenshots · Image & Media
Powerful open-source screenshot and screen recording tool for Windows.
Hosting & Collaboration · Git & Version Control
The badge service for READMEs — build status, version, downloads and custom badges as compact SVGs.
UI Libraries · Frontend
Adaptive design system for Svelte and React on Tailwind, with themes and accessible components.
API Protocols · Backend
Reliable bidirectional realtime communication over WebSockets.
Programming Languages
Official Solidity language site for Ethereum smart contracts.
Frameworks · Frontend
Declarative UI library with fine-grained reactivity and no VDOM.
Frameworks · Backend
The Java ecosystem for building production-grade applications.
Frameworks · Backend
Opinionated Spring setup for standalone production-ready apps.
ORMs · Backend
The Python SQL toolkit and ORM standard.
Relational · Database
Self-contained, serverless, embedded SQL database engine.
Penetration Testing · Security
Open-source penetration testing tool that automates SQL injection detection and exploitation.
Terminals & Shells · Development Environment
Fast, customizable shell prompt written in Rust, works with any shell.
PDF Tools · PDF & Documents
Self-hosted PDF toolbox with 50+ operations, locally run.
Build & Lint · Frontend
Industry-standard workshop for building, testing and documenting UI components.