PyWhy (originally Microsoft Research) · Econometrics & causal inference
Python causal-inference library organized around model, identify, estimate and refute steps, with graphical causal models for attribution, counterfactuals and root-cause analysis
TypeScript ORM with SQL-like query builder, schema defined in code, migrations through Drizzle Kit, and support for PostgreSQL, MySQL and SQLite drivers
Stanford NLP and the DSPy community · Prompting, evaluation & observability
Python framework for programming language-model pipelines with typed signatures and modules, then optimizing prompts and weights automatically against a metric
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
Open-source virtual whiteboard for hand-drawn-style diagrams with live collaboration, embeddable as a React component, plus a hosted Excalidraw+ service
Sebastián Ramírez (tiangolo) and FastAPI contributors · API development & tooling
In-depth entry
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
Git project (Software Freedom Conservancy) · Version control & code hosting
In-depth entry
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
Google (Chrome DevTools team) · Programming languages & runtimes
Statically typed, garbage-collected language from Google that compiles to single binaries and is widely used for servers, CLIs and infrastructure tooling
Hosting platform for open models, datasets and Spaces demo apps built on git repositories and Xet storage, with Inference Providers, Endpoints, Jobs and an open-source Python client and CLI
Jason Liu and contributors (567 Labs) · Agent frameworks & orchestration
Python library for extracting validated structured data from LLM responses using Pydantic models, with automatic retries, streaming partials and support for many providers
LangChain, Inc. · Agent frameworks & orchestration
Open-source Python and JavaScript framework whose create_agent harness builds tool-using agents on the LangGraph runtime with swappable model providers and middleware
MITOpen sourceFreeLocalSelf-hostedNov 2, 2026
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