Install

$ python3 -m pip install flit

Flit requires Python 3 and therefore needs to be installed using the Python 3 version of pip.

Python 2 modules can be distributed using Flit, but need to be importable on Python 3 without errors.

Usage

Say you’re writing a module foobar — either as a single file foobar.py, or as a directory — and you want to distribute it.

1. Make sure that foobar’s docstring starts with a one-line summary of what the module is, and that it has a __version__:

   """An amazing sample package!"""
   
   __version__ = "0.1"

2. Install flit if you don’t already have it:

   python3 -m pip install flit

3. Run flit init in the directory containing the module to create a pyproject.toml file. It will look something like this:

   [build-system]
   requires = ["flit_core >=3.2,<4"]
   build-backend = "flit_core.buildapi"
   
   [project]
   name = "foobar"
   authors = [{name = "Sir Robin", email = "robin@camelot.uk"}]
   dynamic = ["version", "description"]
   
   [project.urls]
   Home = "https://github.com/sirrobin/foobar"

   You can edit this file to add other metadata, for example to set up command line scripts. See the pyproject.toml page of the documentation.

   If you have already got a flit.ini file to use with older versions of Flit, convert it to pyproject.toml by running python3 -m flit.tomlify.

4. Run this command to upload your code to PyPI:

   flit publish

Once your package is published, people can install it using pip just like any other package. In most cases, pip will download a ‘wheel’ package, a standard format it knows how to install. If you specifically ask pip to install an ‘sdist’ package, it will install and use Flit in a temporary environment.

To install a package locally for development, run:

flit install [--symlink] [--python path/to/python]

Flit packages a single importable module or package at a time, using the import name as the name on PyPI. All subpackages and data files within a package are included automatically.

Contributing

To work on Flit, see Developing Flit in the documentation. The issue tracker is on GitHub.

Please do not use AI/LLMs to work on Flit; see the development page for more details.