Problem

derivationStrict is not mentioned in the manual.

Should it be documented? Yes, because it is arguably a better function than derivation:

• it is at least as capable as derivation
• it doesn't return its arguments unnecessarily (blurring what's the actual interface of a package)
• it's more efficient because it does less unnecessary attrset stuff
• its returned attrNames are more predictable than those of derivation and (by extension) Nixpkgs mkDerivation,
  • permitting more laziness when wrapped sensibly (not widely relevant, but even a couple percent of instantiations saved is a win)

Proposal

Document the derivation arguments on a separate page about derivations. This page is store-level documentation.
Document both builtins as usual, referring to the derivation page, and a paragraph about the return value and how it relates to the outputs argument.

Checklist

• checked latest Nix manual (source)
• checked open documentation issues and pull requests for possible duplicates

Priorities

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