Directory

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

Extensible Rust query engine built on Apache Arrow offering SQL and DataFrame APIs, Parquet readers and an optimizer for embedding in data systems

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

Kevin Sheppard's Python package for univariate ARCH/GARCH volatility models, bootstraps, multiple-comparison procedures, unit-root and cointegration tests

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

Microsoft's multi-agent framework (Core, AgentChat, Extensions, Studio) for Python and .NET, now archived with users directed to Microsoft Agent Framework

Rust-based formatter and linter for JavaScript, TypeScript, JSX, JSON, CSS and GraphQL that replaces Prettier and ESLint with one binary

Open-source, offline-first API client that stores collections as plain-text .bru files in a Git repository, with a CLI for running requests in CI

Redis-backed job and message queue for Node.js (with a Python port) offering workers, flows, rate limiting, repeatable jobs and a commercial Pro tier

All-in-one JavaScript and TypeScript runtime, package manager, bundler and test runner built on JavaScriptCore by Oven

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 node-based interface and inference engine for diffusion and other generative models (image, video, audio, 3D), runnable locally with desktop apps or as a hosted cloud

Open-source crawling and scraping library for Node.js/TypeScript and Python that unifies HTTP and headless-browser crawlers with queues, proxies, fingerprints and storage

End-to-end and component testing framework that runs tests inside the browser with an interactive runner, paired with the commercial Cypress Cloud

Python library for parallel and distributed computing that scales pandas, NumPy and custom task graphs from a laptop to a cluster

Secure-by-default JavaScript and TypeScript runtime from Deno Land with web-standard APIs, built-in tooling and an optional hosted Deploy service

React-based static site generator from Meta for documentation sites with MDX content, versioning, localization and a plugin architecture

Python causal-inference library organized around model, identify, estimate and refute steps, with graphical causal models for attribution, counterfactuals and root-cause analysis

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

Python framework for programming language-model pipelines with typed signatures and modules, then optimizing prompts and weights automatically against a metric

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

Python library for heterogeneous treatment-effect estimation with machine learning: double ML, doubly robust learners, causal forests, meta-learners, IV and policy learning

MIT-licensed Python library for SEC EDGAR: company and filing objects, XBRL financial statements, Form 3/4/5, 13F and proxy parsing into pandas, with the SEC identity requirement built in