Directory

Event-driven HTTP server, reverse proxy, load balancer and mail proxy, distributed as open source under the 2-clause BSD license with a commercial Plus edition

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

Foundational Python library for n-dimensional arrays, vectorized math, linear algebra, random numbers and the array API used by the scientific stack

JavaScript data notebooks and the open-source Observable Framework static-site generator for data apps, from the maintainers of D3 and Plot

Modular open-source business suite (CRM, invoicing, accounting, inventory, website, HR) with an LGPL community edition and a hosted or licensed enterprise edition

Open-source runtime and model manager for running open-weight LLMs locally on macOS, Windows and Linux, with a REST API, OpenAI- and Anthropic-compatible endpoints and optional cloud models

Open-source implementation of the MPI message-passing standard used to run tightly coupled parallel programs across the nodes of a cluster

Lightweight open-source Python and TypeScript framework for agents, handoffs, guardrails, sessions and tracing, defaulting to OpenAI's Responses API with adapters for other providers

Open catalog of the global research system: works, authors, sources, institutions and topics under CC0, served by a REST API, web app and S3 snapshot

Apache-2.0 search and analytics suite forked from Elasticsearch and Kibana, governed by the OpenSearch Software Foundation

Reference implementation of the SSH protocol from the OpenBSD project: remote shell, file transfer, port forwarding, key agent and certificate authority tooling

Collaboratively edited world map database released under the ODbL, with planet files, an editing API and derived tiles and extracts

Community fork of Terraform under the Linux Foundation, keeping the HCL language, provider ecosystem and state model under the MPL-2.0 license

Free, open-source research management platform from the Center for Open Science for projects, preregistrations, registries, preprint services and linking outputs across storage providers

Collaborative online LaTeX editor with real-time co-editing, templates and reference-manager sync, available as a hosted service and an AGPL self-hosted edition

Read-only query service for OpenStreetMap data using the Overpass QL language, available on public instances or self-hosted

The standard Python DataFrame library for labeled tabular data, time series and I/O to CSV, Excel, SQL, Parquet and more

Lightweight Python library for declaring and validating DataFrame schemas for pandas, Polars, PySpark and other backends, with type-hint style models

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

Node.js job queue that uses PostgreSQL tables and SKIP LOCKED for reliable background jobs, scheduling and retries without a separate broker

PostgreSQL extension adding vector types, distance operators and HNSW/IVFFlat indexes for similarity search inside the database

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

MIT-licensed interactive charting libraries for Python (plotly.py), JavaScript (plotly.js) and R, plus the Dash framework for analytical web apps

Production process manager for Node.js and other long-running programs with cluster mode, log handling, restart policies and boot-time startup scripts