finstr is a bullshit-free image gallery generator. It produces pages according to a template and groups images by tag or month. Releases can be found at releases.gutmet.org.
If you want to build the executable yourself, you need go1.11+ with module support. Checkout the repository and run 'go build cmd/finstr.go'.
Put the executable somewhere in your path, create a folder for your gallery, then
> cd YOUR_FOLDER > finstr init
Put some .jpgs inside the img folder. Tag them by creating files with the same name but .tags suffix. Each line is a tag, then
> finstr gen > cd pages > firefox index.html
finstr has also been integrated into the static site generator wombat.