You can easily download the app from the newest release and install it with a little tweak.
The problem is, apple just allows signed apps to be installed. This means that macOS adds an attribute (tag) you first need to remove, to install it.
cd <path_of_downloaded_folder>
xattr -d com.apple.quarantine Timer3000.app
Another way would be to just download the source code, Xcode and then build, archive and copy the app for yourself.