Flit is a simple way to put Python packages and modules on PyPI. It tries to require less thought about packaging and help you avoid common mistakes. See Why use Flit? for more about how it compares to other Python packaging tools.
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.
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"Install flit if you don’t already have it:
python3 -m pip install flit
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.
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.
Release files for flit 4.1.0
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| flit-4.1.0.tar.gz | 157.1 kB | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| flit-4.1.0-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 209.2 kB
Release files / flit-4.1.0.tar.gz
| Download URL | flit-4.1.0.tar.gz |
|---|---|
| Size | 157.1 kB |
| Tags | Source |
|
SHA-256 checksum How to use checksums |
18b463c435db03b8cbecf139b6b0bb285b2dfd8a7e623558136abd66f4a04af4
|
|
BLAKE2b-256 checksum How to use checksums |
4758a9f301c4edb50a15ef40e85bebbd33ff3bdd4b80cf35798dc9d6f7f21044
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/7.0.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Sep 16, 2026.
Transparency logRelease files / flit-4.1.0-py3-none-any.whl
| Download URL | flit-4.1.0-py3-none-any.whl |
|---|---|
| Size | 52.2 kB |
| Tags | Python 3 |
|
SHA-256 checksum How to use checksums |
4feee56693b32d1ad2b04e727372b6bf3f3f62d1feda78ab5a7b97091c3f0158
|
|
BLAKE2b-256 checksum How to use checksums |
3ee9b00421707c286eb60b1ce5ad4acafe4058779d164f6aea73ff6acc3d5458
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/7.0.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Sep 16, 2026.
Transparency log