Directory

Open-source C++ library for quantitative finance covering instruments, term structures, pricing engines and calendars, with Python and other bindings

Open-source scientific publishing system from Posit that renders Markdown with executable Python, R, Julia or Observable code to HTML, PDF, Word, slides, websites and books via Pandoc

Open-source Python framework for distributing tasks, actors and ML workloads across a cluster, with libraries for data processing, training, tuning, serving and reinforcement learning

In-memory key-value data store used as cache, message broker and database, with data structures, Pub/Sub, Streams and, since Redis 8, built-in JSON, search and time-series modules

Encrypted, deduplicating backup program written in Go that stores snapshots in local, SFTP, S3-compatible and many cloud backends

Mature open-source Python framework for writing crawlers (spiders) that fetch pages asynchronously, extract structured items and export them through pipelines

Channel-based team messaging platform from Salesforce with threads, huddles, canvases, workflow automation and an extensive bot and app API

Public-domain embedded SQL database engine that stores a whole database in one file and ships inside most operating systems and browsers

Python library for estimating statistical and econometric models with R-style formulas, rich result summaries and tests: OLS, GLM, discrete choice, ARIMA, state space, VAR and more

Apple's compiled, memory-safe, multi-paradigm language for Apple platforms, Linux, Windows and embedded targets, developed in the open at swift.org

WireGuard-based mesh overlay network with a hosted coordination service, identity-provider login, access policies, MagicDNS and features such as Tailscale SSH, Serve and Funnel

The comprehensive free TeX distribution for Linux, macOS and Windows, released yearly with the tlmgr package manager and all major engines, packages and fonts

Statically typed superset of JavaScript from Microsoft that compiles to plain JavaScript and powers editor tooling across the web ecosystem

Markup-based typesetting system with an Apache-2.0 compiler written in Rust and a collaborative web app, positioned as a faster, simpler alternative to LaTeX

Rust-based Python package and project manager from Astral that replaces pip, venv, pip-tools and pyenv with one command-line tool

Free, extensible code editor from Microsoft with a large extension marketplace, integrated terminal, debugging, remote development and built-in AI assistance

Minimal, high-speed VPN protocol and implementation built on modern cryptography, included in the Linux kernel and available on macOS, iOS, Windows, Android and BSD

Apple's integrated development environment and toolchain for building, debugging, testing and submitting apps for iOS, macOS and other Apple platforms

Free, open-source reference manager with browser connectors, word-processor plugins, a PDF reader, group libraries and optional paid file storage