I absolutely adore doing shell.nix environments and flakes. I basically don't have anything installed that I don't need on a daily basis. I use syncthing to keep a folder full of shell environments backed up.

cd /nixShells/video nix-shell

BOOM, I have yt-dlp, ffmpeg-full, mpv, timg, kdenlive, python 3.12 with a bunch of subrip and AI subtitle generators. I do what is needed and exit and it's all gone.

I keep one for wine, one for mp3, one for parsec, one for video

Then I have flakes for real development work.

admittedly, it's a lot :)

Don't worry. I tried it for about 2 years and didn't quite get the hang of it. Back on Arch now. NixOS really has a steep learning curve and not nearly enough documentation.

If you want to explore other immutable and declarative OSes – as well –, you could take Guix for a spin, too (and you can install things such as proprietary software with the NonGuix software repository, in case that's a concern any).