Directory

Lightweight open-source JavaScript library for interactive tile-based web maps with markers, vector layers and a large plugin ecosystem

Open-source functional programming language and interactive theorem prover with dependent types, the Mathlib mathematics library and VS Code tooling, stewarded by the Lean FRO

Open-source vector-tile map renderers for web (GL JS) and native platforms, forked from Mapbox GL and governed by a community organisation

JavaScript library that renders flowcharts, sequence, class, state, ER, Gantt and other diagrams from a Markdown-like text syntax

Python static site generator for project documentation that builds a navigable site from Markdown files and a single YAML configuration

Open JSON-RPC standard for connecting AI applications to tools, data and prompts through servers, now stewarded under the Linux Foundation with SDKs in many languages

Modal, terminal-based text editor forked from Vim with Lua configuration, a built-in LSP client and Tree-sitter parsing

React framework from Vercel for full-stack web applications with file-based routing, server components, server-side rendering, static generation and API route handlers

Server-side JavaScript runtime built on the V8 engine, governed by the OpenJS Foundation, with npm as its package ecosystem

Vendor-neutral, machine-readable standard for describing HTTP APIs in JSON or YAML, maintained by the OpenAPI Initiative under the Linux Foundation

Universal document converter that translates between Markdown, LaTeX, HTML, DOCX, EPUB, Typst, Jupyter and dozens of other formats, with citeproc and Lua filters

Microsoft's browser automation and end-to-end testing framework driving Chromium, Firefox and WebKit from one API in TypeScript, Python, Java and .NET

Opinionated code formatter for JavaScript, TypeScript, CSS, HTML, Markdown, YAML and more that reprints code from its syntax tree with few options

TypeScript ORM with a declarative schema language, generated type-safe client and migration tooling, from the company that also offers Prisma Postgres and related hosted services

Node.js library from the Chrome team for controlling Chrome and Firefox over the DevTools Protocol or WebDriver BiDi, used for scraping, screenshots, PDFs and testing

Python data-validation library using type hints to parse, validate and serialize models, with a Rust core; the schema layer behind FastAPI and many LLM SDKs

Python testing framework with plain assert statements, fixtures, parametrization and a large plugin ecosystem, the de facto standard for Python test suites

General-purpose, dynamically typed programming language with a large standard library and the dominant ecosystem for data science and machine learning

Language and environment for statistical computing and graphics, with the CRAN package archive and a strong base in academic statistics and econometrics

Component-based JavaScript library for building user interfaces, created at Meta, with hooks, a declarative rendering model and server components

Posit's open-source integrated development environment for R, with console, editor, plots, environment panes, Quarto/R Markdown authoring and Python via reticulate

Compiled systems programming language with ownership-based memory safety, the Cargo build tool and no garbage collector

Static analysis engine that matches code patterns written in the target language's own syntax, with an LGPL community edition and a commercial AppSec platform

Collection of accessible React components built on Radix primitives and Tailwind CSS that are copied into a project's source rather than installed as a dependency