zuv 0.4.0

Bundle any uv project into a single runnable .py file.

zuv

Pack your uv project into one .py file. Hand it over, drop it on a server, email it — uv run app.zuv.py and it works.

Why

• One file, no setup. No zip + README + requirements.txt + venv dance. Recipient runs one command.
• Cross-platform, cross-Python. Same file works on Windows / Linux / macOS and any Python minor version (bytecode is built on the target).
• Tiny. ~10 KB even for a FastAPI app — deps install at first run, they're not embedded (unless you ask with --deps).
• Just uv. No bespoke runtime, no PyInstaller-style freezing. The bundle is a PEP 723 script; uv run is the entrypoint.

Install

uv tool install zuv

Quick start

zuv build                       # -> ./dist/<name>.zuv.py
uv run dist/<name>.zuv.py       # run it

dist/ is wiped on every build. Bundles ship .py sources (no bytecode), so the same file works on any OS and any Python minor version. First run extracts into dist/.zuv/<name>_<hash>/, installs deps into a local .venv, runs your entry. Later runs skip extraction.

Commands

zuv build [project] [flags]

arg / flag	what it does
project	Path to the uv project (containing pyproject.toml). Default: current directory.
-o, --output	Output file path. Default: ./dist/<project-name>.zuv.py (or .zuv.zip with --zip).
-e, --entry	Entry script relative to project root. Default: [tool.zuv].entry, then src/main.py, then main.py.
--zip	Wrap the .zuv.py in a .zuv.zip with run.bat (Windows) + run.sh (Unix/macOS) launchers. The launchers install uv from https://astral.sh/uv if missing, then run the bundle. For recipients with neither uv nor Python.
--deps [LIST]	Embed wheels for the locked deps so the bundle runs offline. Bare = current OS only. all = every supported platform. Comma list = pick from windows, linux, linux-arm, macos, macos-arm. Wheels are tied to the Python minor you build with. Note: wheels can't carry OS libs (libGL, libpq, …); on bare Linux, apt install what ImportError names. Prefer -headless variants.
--no-compile	Tell the loader to skip the first-run .py → .pyc compile. Cache stays as plain .py; per-import startup is slower.
--update-repo REPO	Make the bundle self-update from a GitHub or GitLab repo's Releases. Accepts a URL (https://github.com/user/repo, https://gitlab.com/user/repo) or shorthand (user/repo → GitHub, gitlab:user/repo → GitLab). On every startup it asks the Releases API for the named asset and the release's tag_name. If the bundled [project] version from pyproject and the remote tag both parse as dotted-int versions, the loader skips when local ≥ remote (no prompt for older or equal). Otherwise (e.g. rolling latest tag) it falls back to comparing the asset's id; prompts install latest version? [Y/n] when something changed. Declined versions are remembered. Non-TTY runs skip silently. Private repos: set $GH_TOKEN (GitHub) or $GITLAB_TOKEN (GitLab). ZUV_NO_UPDATE=1 disables.
--update-tag TAG	Release tag to fetch the asset from. Default: latest (special value: hits the provider's /releases/latest endpoint). Use a fixed tag to pin recipients to one release.
--update-file FILENAME	Asset filename inside the release. Default: <output-stem>.zuv.py. Lets one release host several bundles (e.g. fastapi.zuv.py, dashboard.zuv.py).

zuv run <file> [-- script-args...]

Thin wrapper around uv run <file>. Identical to running the bundle directly with uv.

zuv inspect <file>

Print the entry, build hash, sha256, PEP 723 metadata, and a summary of the embedded loader bytecode. Payload is elided.

zuv clean [target]

Remove every .zuv/ extraction cache under target (default: cwd). target can be a directory or a built .zuv.py (its parent is used).

Runtime env vars

var	default	purpose
ZUV_CACHE_DIR	next to script	Override where the bundle extracts.
ZUV_MAX_EXTRACT_BYTES	2 GiB	Decompression-bomb cap.
ZUV_NO_UPDATE	(unset)	If set, disables the --update-repo self-update check at startup.
GH_TOKEN / GITHUB_TOKEN	(unset)	Sent as Authorization: Bearer … on GitHub update checks. Required for private GitHub repos.
GITLAB_TOKEN	(unset)	Sent as PRIVATE-TOKEN: … on GitLab update checks. Required for private GitLab repos.

If the script's directory isn't writable, the loader falls back to $XDG_CACHE_HOME/zuv / %LOCALAPPDATA%\zuv / ~/.cache/zuv.

How it works (1 paragraph)

The output is a PEP 723 script: shebang, metadata, a base85-encoded tar.xz of your project (_ZUV_PAYLOAD), and a tiny loader (_ZUV_LOADER) that verifies the sha256, extracts into .zuv/<stem>_<hash>/, and runs uv run --project <extracted> <entry>. Deps install at first run, so the bundle stays small.

Caveat

Don't name your project the same as one of its dependencies (fastapi depending on fastapi confuses uv). Use fastapi-example or similar.

Examples

zuv build examples/bigtest && uv run dist/bigtest.zuv.py
zuv build examples/fastapi && uv run dist/fastapi.zuv.py