Thank you, TIL about ubi! My brain is now compiling a list of places where this will replace either a shell script or flake for my projects :).
Tasks sounds similar process-compose which is bundled into Devbox. I'll have to read up more on tasks though to see if that's an accurate assessment.
Nix is definitely a double-edged sword... One thing I like about Devbox is that it keeps Nix mostly (!) out of sight, mostly unless I want a binary from a GitHub release :).
FYI, ubi is just one of the backends. Besides many languages specific backends (cargo, go, ...), it has 3 backends that support generic packages - asdf, vfox and its own (core). Besides, the default backends are defined for many packages, so that you can let mise choose it for you.