Express
OpenJS Foundation · Web frameworks & UI
Minimal, unopinionated web framework for Node.js with routing and middleware, the long-standing default for HTTP servers in the Node ecosystem
129 tools
OpenJS Foundation · Web frameworks & UI
Minimal, unopinionated web framework for Node.js with routing and middleware, the long-standing default for HTTP servers in the Node ecosystem
Sebastián Ramírez (tiangolo) and FastAPI contributors · API development & tooling
Python web framework for building HTTP APIs from type-annotated functions, with automatic validation through Pydantic and generated OpenAPI documentation
Laurent Bergé · Econometrics & causal inference
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
GeoPandas developers (NumFOCUS affiliated) · GIS & mapping
Python library extending pandas with geometry columns, spatial operations, reprojection, spatial joins and file I/O for vector geodata
Git project (Software Freedom Conservancy) · Version control & code hosting
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
Gitea Ltd. / Gitea community · Version control & code hosting
Lightweight self-hosted Git forge written in Go with repositories, pull requests, issues, packages and GitHub-compatible Actions, deployable as a single binary
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
Great Expectations project (open-source stewardship by Fivetran) · Data quality & validation
Python data-quality framework that declares Expectations about datasets, validates them against pandas, Spark or SQL sources and produces Data Docs
gretl developers (Allin Cottrell, Riccardo Lucchetti) · Econometrics & causal inference
Free, GPL-licensed cross-platform econometrics program with a GUI, the hansl scripting language and estimators for time series, panels and limited dependent variables
Uber Technologies (open-source project) · GIS & mapping
Hexagonal hierarchical geospatial indexing system from Uber with a C core and bindings for Python, JavaScript, Java and SQL engines
Hoppscotch · API development & tooling
Open-source API client that runs in the browser or as a desktop app, supports REST, GraphQL and realtime protocols, and can be self-hosted for teams
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
JabRef e.V. and contributors · Citation management
Open-source, BibTeX/biblatex-native reference manager for LaTeX users with online fetchers, groups, file linking and editor integration
Google (Chrome DevTools team) · Training & fine-tuning
Python library for NumPy-style array computing with composable transformations (jit, grad, vmap, shard_map) compiled through XLA to CPU, GPU and TPU
OpenJS Foundation · Testing & QA
JavaScript testing framework created at Meta with built-in assertions, mocking, snapshot testing and parallel test execution
The Julia Project · Programming languages & runtimes
Dynamically typed, JIT-compiled language for numerical and scientific computing that aims to combine high-level syntax with compiled-code speed
Keycloak project (CNCF incubating, originated at Red Hat) · Identity & access
Open-source identity and access management server providing single sign-on with OpenID Connect, OAuth 2.0 and SAML, user federation and fine-grained authorization
Cloud Native Computing Foundation · Containers & virtualization
Open-source system for scheduling, scaling and operating containerized workloads across a cluster of machines
Kùzu Inc. (company acquired; project archived) · NoSQL & key-value stores
Embedded property-graph database with Cypher, vector and full-text search; MIT-licensed but archived in October 2025 after the company was acquired
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
LangChain, Inc. · Agent frameworks & orchestration
Low-level orchestration framework and runtime for stateful, long-running agents expressed as graphs, with durable execution, checkpointing, human-in-the-loop and streaming
Lean FRO · Mathematical & statistical computing
Open-source functional programming language and interactive theorem prover with dependent types, the Mathlib mathematics library and VS Code tooling, stewarded by the Lean FRO
Kevin Sheppard · Econometrics & causal inference
Python package by Kevin Sheppard adding panel data, instrumental-variable, system (SUR/3SLS) and asset-pricing estimators missing from statsmodels
ggml-org (Georgi Gerganov and contributors) · Local LLM inference & serving
C/C++ inference engine for LLMs and vision-language models with GGUF quantized weights, Metal, CUDA, Vulkan and other backends, a CLI and an OpenAI-compatible server
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