Directory

Apache-licensed BI web application with SQL Lab, a no-code chart builder, dashboards and connectors to any SQLAlchemy-compatible database

Free, moderated open-access preprint server for physics, mathematics, computer science, statistics, quantitative finance, economics and related fields, with an open API and bulk access

Webrecorder's browser-based web archiving system, available hosted or self-hosted, that crawls sites with real browsers into signed WACZ files replayable with ReplayWeb.page

Modular JavaScript library for bespoke, data-driven web graphics: scales, axes, shapes, layouts, geo projections, transitions and DOM selections

Québec's shared open-data portal where provincial ministries and municipalities publish datasets under a Creative Commons Attribution licence

Free diagramming editor (formerly diagrams.net) for flowcharts, network, UML and architecture diagrams, available as web app, desktop app and integrations

Open-source virtual whiteboard for hand-drawn-style diagrams with live collaboration, embeddable as a React component, plus a hosted Excalidraw+ service

Community-governed self-hosted Git forge forked from Gitea, stewarded by Codeberg e.V., with pull requests, issues, packages and Forgejo Actions

Open-source wealth-tracking web app for stocks, ETFs, crypto and other assets, self-hostable with Docker or used as a hosted service

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

Open-source API client that runs in the browser or as a desktop app, supports REST, GraphQL and realtime protocols, and can be self-hosted for teams

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

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

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

Reactive Python notebook stored as a plain .py file that re-runs dependent cells automatically and doubles as a script or web app

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

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

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

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

Non-profit registry of persistent researcher identifiers (ORCID iDs) with user-controlled records, Public and Member APIs, OAuth sign-in and an annual CC0 public data file

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

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