Directory

Language-independent columnar in-memory format and libraries that let DuckDB, Polars, pandas, Spark and databases exchange tables without copying

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

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

In-process analytical SQL database that queries Parquet, CSV and Arrow data directly from Python, R, Node or the CLI

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

R package for fast estimation of OLS, GLM, Poisson, IV and difference-in-differences models with many fixed effects, clustered errors, multiple estimations and publication tables

Python library extending pandas with geometry columns, spatial operations, reprojection, spatial joins and file I/O for vector geodata

Distributed version control system that records snapshots of a project's history locally and synchronizes them with remotes such as GitHub, GitLab or a bare repository over SSH

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

Community-maintained package manager for macOS and Linux that installs command-line tools (formulae) and desktop apps (casks) from the terminal

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

Embedded property-graph database with Cypher, vector and full-text search; MIT-licensed but archived in October 2025 after the company was acquired

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

C/C++ inference engine for LLMs and vision-language models with GGUF quantized weights, Metal, CUDA, Vulkan and other backends, a CLI and an OpenAI-compatible server

Apple's open-source array framework for machine learning on Apple Silicon, with NumPy-like Python, C++ and Swift APIs and unified CPU/GPU memory

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

Server-side JavaScript runtime built on the V8 engine, governed by the OpenJS Foundation, with npm as its package ecosystem

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

The standard Python DataFrame library for labeled tabular data, time series and I/O to CSV, Excel, SQL, Parquet and more

Universal document converter that translates between Markdown, LaTeX, HTML, DOCX, EPUB, Typst, Jupyter and dozens of other formats, with citeproc and Lua filters

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