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
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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