GTimeLog is a small time tracking application for GNOME. Its main goal is to be as unintrusive as possible.
You can get GTimeLog from the Python Package Index:
pip install gtimelog
Up-to-date packages exist in Debian, Ubuntu, Fedora, and Flathub.
GTimeLog should in theory also run on Windows and Mac OS X, but I don't have convenient installers.
Please report bugs/feature requests on GitHub.
The source code lives on GitHub. Get it with
git clone https://github.com/gtimelog/gtimelog
GTimeLog was written by Marius Gedminas, with contributions from many others. It is released under the terms of the GNU GPL.