Time tracking plasma applet
Author: Jan Grulich <jgrulich@redhat.com>
Released under GPL 2.0+
mkdir build
cd build
cmake .. -DCMAKE_INSTALL_PREFIX=/usr -DQML_INSTALL_DIR:PATH=$(QT_SELECT=5 qmake -query QT_INSTALL_QML)
make
make install
If you don't think that compilication is a good option for you, you can try to ask your distribution packagers to include it in official repositories.
List of distributions providing plasma-timekeeper in their repositories:
Archlinux - https://aur.archlinux.org/packages/timekeeper-git