The comment
a dirty hack that should be removed
has led me to believe that nixpkgsFun isn't the right solution,
but bypassing it is worse, because it creates a second, inner
overriding mechanism that doesn't pass its changes to the old,
outer overriding mechanism.
Before this change:
nix-repl> ((import <nixpkgs> {}).appendOverlays([(f: s: { foobarbaz = "ok"; })])).foobarbaz
"ok"
nix-repl> ((import <nixpkgs> {}).appendOverlays([(f: s: { foobarbaz = "ok"; })])).pkgsCross.aarch64-multiplatform.foobarbaz
error: attribute 'foobarbaz' missing
at «string»:1:1:
1| ((import <nixpkgs> {}).appendOverlays([(f: s: { foobarbaz = "ok"; })])).pkgsCross.aarch64-multiplatform.foobarbaz
| ^
2|
After this change:
nix-repl> ((import ./. {}).appendOverlays([(f: s: { foobarbaz = "ok"; })])).pkgsCross.aarch64-multiplatform.foobarbaz
"ok"
Thanks to samueldr for discovering this problem.
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