I have also customized Fastfetch/HyFetch output so that it accurately prints the number of packages I have installed. The Fastfetch configuration file used is located in ~/lfs_dotfiles/config.jsonc. The HyFetch configuration files are also in ~/lfs_dotfiles/hyfetch.json.
In the screenshot above, 852 [ 735, 2, 86, 29] means that 852 packages are installed in total. Of them 735 were installed via custom build scripts in ~/lfs_packaging. 2 Julia packages were installed; this package is Julia itself which was installed via juliaup (the compilation process of Julia is incredibly complex and even requires its own custom build of LLVM). 86 Python packages were installed via pip. 29 R packages were installed.
585 refers to number of custom package inventory git repository commits I have published. I include it in Fastfetch output as a way of tracking the versions of custom packages.
There is one systemd service file in ~/lfs_dotfiles/systemd/user/lfs-download.service to autostart ~/lfs_scripts/lfs-download.sh. This downloads LFS, BLFS and SFLS HTML files for use by the version= lines of build.sh files in ~/lfs_packaging.