Directory

Rust-based DataFrame library with Python, Rust, Node and R bindings offering lazy query optimization, multithreading and Arrow-native memory

Posit's multi-language data-science IDE built on Code OSS, with first-class R and Python consoles, variables and plots panes, under the Elastic License 2.0

Python workflow orchestration library and server where decorated functions become observable, retryable flows, with Prefect Cloud as hosted option

Open-source computational notebook ecosystem: the .ipynb format, kernels for Python, R and Julia, JupyterLab and Notebook interfaces and JupyterHub

Python IDE from JetBrains with deep static analysis, refactoring, debugging, scientific tooling and a unified free core with a paid Pro tier

Python data-validation library using type hints to parse, validate and serialize models, with a Rust core; the schema layer behind FastAPI and many LLM SDKs

Type-safe Python agent framework from the Pydantic team with validated structured outputs, dependency injection, swappable model providers, MCP, durable execution and evals

Python library for portfolio optimization: efficient frontier, Black-Litterman, hierarchical risk parity and discrete allocation

Python testing framework with plain assert statements, fixtures, parametrization and a large plugin ecosystem, the de facto standard for Python test suites

General-purpose, dynamically typed programming language with a large standard library and the dominant ecosystem for data science and machine learning

Open-source deep-learning framework with eager tensors, autograd, torch.compile and distributed training, governed by the PyTorch Foundation and the base of most LLM tooling

Open-source desktop GIS for viewing, editing, analysing and publishing vector and raster geodata, extensible with Python plugins

Algorithmic trading platform built on the open-source LEAN engine, with cloud backtesting, research notebooks and brokerage-connected live trading

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 library for evaluating LLM and RAG applications with LLM-driven and custom metrics, experiments, dataset management and result tracking

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

Python library for quantitative portfolio optimization with many risk measures, robust estimators and hierarchical clustering models

BSD-licensed Python machine-learning library for classification, regression, clustering, dimensionality reduction, preprocessing and model selection on NumPy and SciPy

Core open-source Python library for scientific computing on NumPy arrays: optimization, integration, interpolation, linear algebra, sparse matrices, statistics, signal processing

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

Python library for computing and training embedding, cross-encoder reranker, sparse and multi-vector retrieval models, maintained by Hugging Face with thousands of pretrained models on the Hub

Python documentation generator using reStructuredText or MyST Markdown with cross-referencing, API autodoc and output to HTML, PDF via LaTeX, ePub and man pages

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