Directory

SQL-first transformation framework that compiles templated models, tests and documentation into warehouse tables; open-source Core plus a commercial platform

Distributed search and analytics engine on Apache Lucene with full-text, aggregations, vector search and ES|QL; triple-licensed AGPL, SSPL and Elastic License

Web data API that scrapes, crawls, maps and searches websites and returns clean Markdown or structured JSON for LLM pipelines, with an AGPL-licensed self-hostable core

Lightweight self-hosted Git forge written in Go with repositories, pull requests, issues, packages and GitHub-compatible Actions, deployable as a single binary

Microsoft-owned code hosting platform for Git repositories with pull requests, issues, Actions CI/CD, package registry, Copilot and the largest open-source community

Dashboarding and alerting platform that visualizes metrics, logs and traces from Prometheus, SQL databases and dozens of other data sources

Open-source LLM observability and evaluation platform: tracing, LLM-as-judge and human evals, prompt management, datasets and cost dashboards, self-hostable or as Langfuse Cloud

Open-source Python SDK and self-hosted AI gateway that calls 100+ LLM providers in the OpenAI format, with routing, fallbacks, virtual keys, budgets, spend tracking and logging callbacks

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

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

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

Open-source computational notebook ecosystem: the .ipynb format, kernels for Python, R and Julia, JupyterLab and Notebook interfaces and JupyterHub

Open-source vector search engine written in Rust with filterable HNSW indexes, sparse and multi-vector support, REST/gRPC APIs and a managed cloud

Algorithmic trading platform built on the open-source LEAN engine, with cloud backtesting, research notebooks and brokerage-connected live trading

Open-source Python framework for distributing tasks, actors and ML workloads across a cluster, with libraries for data processing, training, tuning, serving and reinforcement learning

Markup-based typesetting system with an Apache-2.0 compiler written in Rust and a collaborative web app, positioned as a faster, simpler alternative to LaTeX

Free general-purpose research repository operated by CERN that assigns DOIs to datasets, software, papers and other outputs, with a REST API, OAI-PMH, GitHub release archiving and CC0 metadata

Free, open-source reference manager with browser connectors, word-processor plugins, a PDF reader, group libraries and optional paid file storage