Nix is interesting and fine if you are a solo developer with time to learn the details. I did try it briefly but find the learning curve of rtx is near zero - it does less than Nix but is very easy to adopt in a team. Compatible with asdf but faster and easier in some way, and actively developing.

I recently started using rtx and I’m a big fan.

Works for a long list of tools and makes it very easy to remove lots of install commands and just do “rtx install” in any directory to install and switch to right versions of a set of tools. Also works great on CI using same configuration files.