Free
PostCSS
Open SourceEcosystem · CSS Tools
Tool for transforming CSS with JavaScript plugins.
csstoolingplugins
Browse the complete directory — use filters to narrow down.
Ecosystem · CSS Tools
Tool for transforming CSS with JavaScript plugins.
Mobile Backend & Services · Mobile Development
Open-source product analytics, feature flags and session replay.
Programming Languages
Official PowerShell documentation from Microsoft.
Hooks & Commits · Git & Version Control
Framework for managing and maintaining multi-language pre-commit hooks.
Pipelines & ETL · Data & Analytics
Python workflow orchestration that feels like writing scripts — dynamic DAGs, retries, scheduling and a rich UI.
Ecosystem · CSS Tools
Open-source Tailwind component collection with rich interactive JS widgets and an extensive Figma kit.
Build & Lint · Frontend
Opinionated code formatter supporting many languages.
UI Libraries · Frontend
The Angular edition of the Prime suite: 90+ components with a standout data table.
Design Systems · Design & Prototyping
GitHub's design system with React components and tokens.
UI Libraries · Frontend
The React edition of the Prime suite: 90+ components, theming presets and a powerful data table.
UI Libraries · Frontend
Rich Vue UI suite: 90+ components, themed presets and a massive data-table implementation.
ORMs · Backend
Type-safe ORM for TypeScript/Node with schema migrations and Studio.
Logs & Metrics · Monitoring & Observability
The standard open-source metrics collection and alerting toolkit.
Agent & LLM Frameworks · AI for Developers
The most comprehensive open guide to prompting techniques.
Agent & LLM Frameworks · AI for Developers
Open-source tool for testing and evaluating LLM prompts and models.
References · Documentation & Learning
The largest curated directory of free public APIs — 1,400+ entries across 40 categories with auth requirements noted.
Infrastructure as Code · DevOps
Infrastructure as code in real programming languages.
E2E & Browser · Testing
Node.js library to control Chrome via the DevTools Protocol.
Unit & Component · Testing
The de-facto testing framework for Python: plain asserts, powerful fixtures and a rich plugin ecosystem.
Vector Databases · AI for Developers
Open-source vector database written in Rust, with cloud offering.
UI Libraries · Frontend
Vue framework that targets SPA, PWA, SSR, mobile (Capacitor) and desktop (Electron) from one codebase.
Cheatsheets · Documentation & Learning
Clean, searchable cheat sheet collection for developers.
JSON · Data Formats
Generate types and serializers from JSON: TypeScript, Java, Kotlin, Go and more.
Frameworks · Frontend
Resumable framework with lazy execution for near-instant loads.