Python Support

Turnkey provides Python support with Buck2 integration.

Python source in this repo is laid out as a uv workspace, with each package owning its own pyproject.toml and contributing to a shared turnkey.* PEP 420 namespace. This page covers the Buck2 build rules; read the workspace workflow guide first for the overall layout and the uv/Buck2 dual-track model.

Setup

Add to toolchain.toml:

[toolchains]
python = {}
uv = {}
pydeps-gen = {}

Enable Python dependencies in flake.nix:

turnkey.toolchains.buck2.python = {
  enable = true;
  depsFile = ./python-deps.toml;
};

Project Structure

my-project/
├── pyproject.toml
├── uv.lock
├── python-deps.toml      # Generated from uv.lock
└── python/
    └── mypackage/
        ├── __init__.py
        ├── main.py
        └── rules.star

Build Rules

In rules.star:

load("@prelude//python:python.bzl", "python_library", "python_binary", "python_test")

python_library(
    name = "mypackage",
    srcs = glob(["**/*.py"]),
    deps = ["pydeps//requests:requests"],
)

python_binary(
    name = "main",
    main = "main.py",
    deps = [":mypackage"],
)

python_test(
    name = "test",
    srcs = ["test_main.py"],
    deps = [":mypackage"],
)

External Dependencies

Reference packages via the pydeps cell:

deps = [
    "pydeps//requests:requests",
    "pydeps//click:click",
]

Auto-Sync

The uv command is wrapped to auto-sync:

uv add requests  # Triggers sync