type-python 0.3.0

A statically-typed authoring language that compiles to standard Python

TypePython

Write richer types. Emit standard Python.

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A statically-typed authoring language that compiles to standard Python.

Write .tpy source files with interface, data class, sealed class, inline generics, and strict null safety. The compiler emits standard .py + .pyi files for Python 3.10-3.14. No custom runtime, no vendor lock-in.

Install

pip install type-python
typepython --help

The Python package bridge supports Python 3.9+. Generated projects can target Python 3.10 through 3.14.

Published wheels bundle the Rust CLI binary. Prebuilt wheels are available for Windows AMD64, macOS x86_64, macOS arm64, and Linux x86_64. Other platforms fall back to the source distribution and require Rust + cargo.

Quick Start

typepython init --dir my-project
cd my-project
typepython check --project .
typepython build --project .

Example source:

# src/app/__init__.tpy

sealed class Expr:
    pass

data class Num(Expr):
    value: int

data class Add(Expr):
    left: Expr
    right: Expr

def evaluate(expr: Expr) -> int:
    match expr:
        case Num(value=v):
            return v
        case Add(left=l, right=r):
            return evaluate(l) + evaluate(r)
    # Compiler proves all cases are covered -- no default needed.

What You Get

Your code (.tpy)	Emitted output (.py / .pyi)
sealed class Expr:	class Expr: # tpy:sealed
data class Num(Expr):	@dataclass plus ordinary class Num(Expr):
interface Drawable:	class Drawable(Protocol):
overload def f(x: int) -> int:	@overload plus ordinary def f(x: int) -> int:
typealias Pair[T] = tuple[T, T]	T = TypeVar("T"); Pair: TypeAlias = tuple[T, T]

• Rich type system -- unknown, dynamic, Never, strict nulls, sealed exhaustiveness, generic defaults, TypeVarTuple
• TypedDict utilities -- Partial, Required_, Readonly, Mutable, Pick, Omit
• Full toolchain -- init, check, build, watch, clean, verify, lsp, migrate
• LSP server -- hover, go-to-definition, references, rename, completions, signature help, diagnostics
• Standard output -- emitted .py + .pyi work with mypy, pyright, and ty out of the box

Documentation

• Getting Started
• Syntax Guide
• Type System
• Configuration
• CLI Reference
• Interoperability
• Language Spec

Links

• Repository
• Issues
• License (MIT)