---
id: basedpyright
version: "1.39.10"
license: unclear
license_treatment: permissive
maintenance: active
---

# basedpyright — static type checking for Python (but based)

License: permissive · Maintenance: active · Downloads: 10.5M/mo

## What it is and what it does

Basedpyright is a maintained fork of Microsoft's Pyright static type checker, designed to add type checking improvements and features from Pylance that are not present in the upstream project. It analyzes Python code for type errors without running it, helping developers catch bugs early and enforce type safety across codebases. The package requires Python 3.8 or later and depends on nodejs-wheel-binaries at runtime, making it suitable for projects that already have Node.js infrastructure or can tolerate that dependency.

The project is actively developed with frequent releases and a substantial community following. It serves developers who want stricter or more feature-rich type checking than standard Pyright provides, particularly those working with modern Python versions (3.8 through 3.14 are supported).

Use it for:

- Enforce type safety in Python projects by catching type errors before runtime.
- Integrate type checking into CI/CD pipelines as part of code quality gates.
- Use enhanced type checking features from Pylance without adopting the full IDE.
- Migrate from Pyright while gaining additional type checking capabilities.
- Validate type annotations in large codebases across Python 3.8+.

## Worth the install?

AI-flagged interpretation of the facts above — verify before relying.

Basedpyright is a static type checker for Python that forks and extends Pyright with additional type checking improvements and Pylance features.

Yes, if you need static type checking for Python and want Pyright with additional improvements. The low install friction, active maintenance, permissive license, and lack of known vulnerabilities make it a solid choice. Verify first whether the specific enhancements over Pyright align with your project's needs by checking the documentation.

## Install

pip install basedpyright
uv add basedpyright
poetry add basedpyright

## Installing basedpyright

Before you install: Low install friction with a single runtime dependency on nodejs-wheel-binaries. The project is actively maintained with a recent release (1 day old) and 3525 repository stars, indicating ongoing development and community engagement.

License in practice: Licensed under MIT (permissive), allowing free use, modification, and distribution with minimal restrictions.

Quickstart:

pip install basedpyright
basedpyright --help

Requires Python 3.8 or later; nodejs-wheel-binaries runtime dependency must be available.

Verify before relying:

- Whether basedpyright can be used as a drop-in replacement for pyright in existing type-checking workflows.
- Specific list of type checking improvements and Pylance features added beyond the upstream pyright.
- Performance characteristics compared to the original pyright implementation.

## Package facts

- License: not declared (permissive)
- Python support: supports_current
- Install friction: low
- Maintenance: active
- Downloads: 10.5M/month (top 5,000 on PyPI)
- Known vulnerabilities: none known

## Tags

python static type checker, type checking tool, pyright fork, python type annotations, static analysis python, type validation, python type linter, type-checking, static-analysis, code-quality

[View on SkillFed](https://skillfed.io/packages/basedpyright) · [View on PyPI](https://pypi.org/project/basedpyright/)