Description
Is your feature request related to a problem? Please describe.
nix build merely creates whatever it is that you pass to it. If that's a derivation path, it doesn't build it. That's a valid behavior despite its name. (I've previously proposed nix create for this behavior, but I can accept this quirk)
Another issue is that it does too much. Not only does it run the builder; it also copies outputs to the store. This may not be useful or desired, for instance when invoking nix in CI.
Describe the solution you'd like
nix derivation build - as a plumbing command - promises very little: only run the builder, (locally or remotely) and don't bother with outputs.
This should require a derivation path, so as not to suffer from the naming problem that nix build has. To build the derivation backing a certain output, add the store level derivationOf operator, ^..
This would make sense to me, but needs validation by actual users (I don't call the nix CLI; I let Hercules CI handle such minutiae for me).
Describe alternatives you've considered
Maybe nix derivation build is expected to be an alias of nix build or vice versa?
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This makes
nix-fast-buildpartially obsolete, and that's a good thing. -
Some destination store parameter, which could be set to empty. I don't like flags that remove functionality. Doing too much shouldn't be the default - it leads to bloated interfaces.
Additional context
Priorities
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