Directory

Python workflow orchestrator for scheduling and monitoring DAGs of tasks, with hundreds of provider packages and managed offerings from several clouds

Open table format for data lakes that adds ACID snapshots, schema and partition evolution and time travel over Parquet, ORC or Avro files

Distributed event streaming platform with durable, partitioned, replayable logs, Kafka Connect connectors and Kafka Streams processing

Distributed data processing engine with DataFrame and SQL APIs in Python, Scala, Java and R, plus structured streaming and MLlib

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

Self-hosted, open-source web archiving tool that saves URLs as HTML, PDF, screenshot, WARC, readable text and media snapshots with a web UI and CLI

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

Go web server and reverse proxy that obtains and renews TLS certificates automatically and is configured with a short Caddyfile or a JSON API

Open-source embedding database with a minimal Python and JavaScript API, usable in-process, as a server or through Chroma Cloud

Open-source columnar OLAP database server for fast aggregations over billions of rows, with MergeTree storage, SQL and a managed ClickHouse Cloud

Asset-oriented Python orchestrator that models pipelines as software-defined data assets with lineage, checks and a hosted Dagster+ option

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

Open-source software that pools several Apple Silicon Macs (and Linux hosts) into one local inference cluster, sharding large models across devices with MLX

Minimal, unopinionated web framework for Node.js with routing and middleware, the long-standing default for HTTP servers in the Node ecosystem

Python web framework for building HTTP APIs from type-annotated functions, with automatic validation through Pydantic and generated OpenAPI documentation

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

Small TypeScript web framework built on Web Standard APIs that runs unchanged on Cloudflare Workers, Deno, Bun, Node.js and other JavaScript runtimes

Open-source identity and access management server providing single sign-on with OpenID Connect, OAuth 2.0 and SAML, user federation and fine-grained authorization

Open-source system for scheduling, scaling and operating containerized workloads across a cluster of machines

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

Low-level orchestration framework and runtime for stateful, long-running agents expressed as graphs, with durable execution, checkpointing, human-in-the-loop and streaming