# Install basedpyright with Homebrew, Nix Pyright fork with various improvements and built-in pylance features. Version 1.39.9 via Homebrew; verified 2026-06-28. Also installable with nix: nix profile install nixpkgs#basedpyright. ## Install ```sh sudo av install brew:basedpyright ``` Additional install commands: ### macOS - Homebrew (100%): ```sh brew install basedpyright ``` Evidence: local Homebrew formula metadata ### Linux - Nix (92%): ```sh nix profile install nixpkgs#basedpyright ``` Evidence: nixpkgs package indexes: pkgs/by-name/ba/basedpyright/package.nix from https://api.github.com/repos/NixOS/nixpkgs/git/trees/master?recursive=1 ## Package facts - **Package key:** brew:basedpyright - **Package manager:** Homebrew - **Version:** 1.39.9 - **Source summary:** Pyright fork with various improvements and built-in pylance features - **Homepage:** - **Last updated:** 2026-06-28T03:19:45Z - **Generated:** 2026-08-03T19:37:03+00:00 ## Executables - basedpyright (alias) - basedpyright-langserver (alias) ## Install behavior - Bottle: not available ## Freshness - Page generated: 2026-08-03 - Package-manager version: 1.39.9 ## Project history and usage basedpyright is a fork of Microsoft's Pyright type checker and language server for Python. It adds stricter defaults, additional diagnostics, PyPI distribution, version pinning, and reimplemented Pylance features for editors outside VS Code. ### Project history The official documentation describes basedpyright as a Pyright fork with type-checking improvements, Pylance features, and more. Its documentation site and README both point to the GitHub repository and organize the project around benefits over upstream Pyright. The release stream tracks upstream Pyright closely. The latest documentation canonical URL observed for this batch was v1.39.9, and GitHub release metadata for v1.39.9 names the paired Pyright version as 1.1.411. ### Adoption history basedpyright is distributed through several developer channels: PyPI, the Visual Studio Marketplace, Open VSX, Sublime Text Package Control, Homebrew, and Nix according to the README badges and input metadata. That spread reflects its role as both a CLI checker and language server. A major adoption hook is that users can install it from PyPI without Node.js, while the VS Code extension uses the same version to avoid different diagnostics between editor and CLI. ### How it is used Users run basedpyright as a command-line type checker or basedpyright-langserver as an editor language server. Configuration follows Pyright-style project configuration in pyrightconfig.json or pyproject.toml. The docs emphasize stricter defaults, new diagnostic rules, baseline support for adopting those rules in existing projects, and Pylance-like language-server behavior outside Microsoft's closed-source Pylance extension. ### Why package nerds care basedpyright is important in package-manager culture because it repackages a Node-centered Python type checker as a Python-installable tool and aligns editor and CLI versions. That solves a real packaging pain point for Python projects that want type checking without a JavaScript toolchain. It also shows a common modern fork pattern: take a successful corporate-backed open-source core, add stricter defaults and features withheld in a closed extension, and distribute it through every editor/package channel where Python developers already work. ### Timeline - 2020s: basedpyright forked Pyright to add stricter checks, Pylance-like features, and packaging changes. - 2020s: Documentation organized a Benefits over Pyright section covering baselines, better defaults, new diagnostics, and language-server improvements. - 2026: v1.39.9 was published with Pyright 1.1.411 alignment according to GitHub release metadata. ### Related projects - Pyright is the upstream Microsoft type checker that basedpyright forks. - Pylance is Microsoft's closed-source VS Code extension whose features basedpyright reimplements for wider editor use. - Mypy, Pyre, and pytype are related Python static type checkers, but basedpyright's direct lineage is Pyright. ### Sources - - - - - source_facts.package-manager ## Security Notes No matching local secret-handling manifest was found for basedpyright. Nucleus package metadata is still published here so future coverage has a stable package URL. ## Configuration and credential file locations These source-backed paths show where this package keeps local settings or durable credentials. Automic Vault can use them as review targets for secret scanning, migration, and command approval. ## Configuration files - Unix: /pyrightconfig.json, /pyproject.toml ## Other Package-Manager Records - Nix - basedpyright: normalized package name match | nixpkgs package indexes: pkgs/by-name/ba/basedpyright/package.nix from https://api.github.com/repos/NixOS/nixpkgs/git/trees/master?recursive=1 ## Combined YAML source View the package source record on GitHub. [combined/basedpyright.yml](https://github.com/mxcl/pkgdb/blob/main/combined/basedpyright.yml) ## Sources - pkg.so package database - Geiger risk classifier - curated configuration and credential file locations - curated package history - pkgdb category and tag curation - external package-manager database matches - cross-ecosystem install command graph