🍎 ApplePy

Create native Python extensions in Swift.

ApplePy lets you build pip install-able Python packages written entirely in Swift — with direct access to Apple frameworks like CoreML, Metal, NaturalLanguage, Security, and more.

• Get started in 30 seconds

  ---

  pip install applepy-cli
  applepy new myproject
  cd myproject && applepy develop
  

  Quickstart

• Write Swift, import from Python

  ---

  @PyFunction
  func hello(name: String) -> String {
      "Hello, \(name)! 🍎"
  }
  

  Macros Reference

• Access Apple frameworks

  ---

  CoreML, Metal, NaturalLanguage, Security — any framework available in Swift is now available from Python.

  Examples

• pip install & publish

  ---

  Build wheels, publish to PyPI. Your users just pip install — no Swift toolchain needed at runtime.

  Building & Packaging

Quick Example

SwiftPython

import ApplePy
@preconcurrency import ApplePyFFI

@PyFunction
func greet(name: String, greeting: String = "Hello") -> String {
    "\(greeting), \(name)! 🍎"
}

@PyModule("mylib", functions: [greet])
func mylib() {}

>>> import mylib
>>> mylib.greet("World")
'Hello, World! 🍎'
>>> mylib.greet("World", "Hi")
'Hi, World! 🍎'

Features

Macro	Purpose
@PyFunction	Expose top-level functions (with default argument support)
@PyClass	Expose structs/classes as Python types
@PyMethod	Mark instance methods for Python
@PyStaticMethod	Mark static methods for Python
@PyProperty	Expose stored properties with getters/setters
@PyEnum	Swift enum → Python IntEnum or class hierarchy
@PyModule	Generate PyInit_ module entry point

Type Conversions

Swift	Python	Direction
Int, Double, Float, Bool	int, float, bool	↔
String	str	↔
[T]	list	↔
[K: V]	dict	↔
Set<T>	set	↔
Optional<T>	None / value	↔
PyTuple2<A,B>, PyTuple3<A,B,C>	tuple	↔

vs PyO3

Dimension	PyO3 (Rust)	ApplePy (Swift)
Macros	#[pyfunction], #[pyclass]	@PyFunction, @PyClass
Memory safety	'py lifetimes	GILGuard: ~Copyable
Build tool	maturin	applepy CLI
Platform	Cross-platform	macOS (Apple frameworks)
Enums	Class-based	IntEnum + class hierarchy

Full comparison