Static Typing with Python¶

Typing PEPs¶

Significant changes to the Python Type System Specification are proposed and discussed in Python Enhancement Proposals (PEPs). See https://peps.python.org/topic/typing for a list of all current and historical typing-related PEPs.

Type Checkers¶

• mypy

• pyrefly

• pyright

• ty

• Zuban

The extent to which these adhere to the specification is monitored by a conformance test suite (results).

Development Environments¶

• PyCharm, an IDE that supports type stubs both for type checking and code completion.

• Visual Studio Code, a code editor that supports type checking using mypy, pyright, or the Pylance extension.

Linters and Formatters¶

• black, a code formatter with support for type stub files.

• flake8-pyi, a plugin for the flake8 linter that adds support for type stubs.

• ruff, a linter built for speed, with support for most of the flake8-pyi rules.

Type-Hint and Stub Integration¶

• autotyping, a tool which infers simple types from their context and inserts them as inline type-hints.

• merge-pyi, a thin wrapper around ApplyTypeAnnotationsVisitor from libCST that integrates .pyi signatures as inline type-hints in Python source code.