Directory

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

Document database storing BSON documents with a rich aggregation pipeline, available as a source-available Community Server or the managed Atlas service

Open-source learning management system used by universities and schools for courses, assignments, quizzes, grading and forums, self-hosted or via MoodleCloud

Oracle's widely deployed open-source relational database server, offered as a GPL community edition and commercial enterprise and cloud editions

Lightweight Go messaging system with core pub/sub and request-reply plus JetStream persistence, key-value and object stores; a CNCF project

Native property-graph database queried with Cypher, offered as a GPL community edition, a commercial enterprise edition and the AuraDB cloud service

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

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

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

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

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

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

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

Daemonless, rootless container engine with a Docker-compatible CLI, companion Buildah and Skopeo tools and a Podman Desktop GUI