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

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

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

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

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 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

Nonprofit certificate authority that issues free, automatically renewable TLS certificates through the ACME protocol

Open-source Python framework for retrieval-augmented agents over your data, with connectors, indexes, query engines and event-driven workflows, alongside the commercial LlamaParse document platform

Open-source vector database from Zilliz with Lite, Standalone and Distributed deployments, many index types and GPU acceleration

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

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