error:
       … while evaluating the attribute 'optionalValue.value'
         at «github:NixOS/nixpkgs/fb7944c166a3b630f177938e478f0378e64ce108?narHash=sha256-EgE0pxsrW9jp9YFMkHL9JMXxcqi/OoumPJYwf%2BOkucw%3D»/lib/modules.nix:1256:5:
         1255|
         1256|     optionalValue = if isDefined then { value = mergedValue; } else { };
             |     ^
         1257|   };

       … while evaluating a branch condition
         at «github:NixOS/nixpkgs/fb7944c166a3b630f177938e478f0378e64ce108?narHash=sha256-EgE0pxsrW9jp9YFMkHL9JMXxcqi/OoumPJYwf%2BOkucw%3D»/lib/modules.nix:1256:21:
         1255|
         1256|     optionalValue = if isDefined then { value = mergedValue; } else { };
             |                     ^
         1257|   };

       … while evaluating definitions from `/nix/store/q7zzr647cmpiv9yciq4vk6hway02qfag-source/builtinModules/packages.nix':

       … while evaluating definitions from `/nix/store/q7zzr647cmpiv9yciq4vk6hway02qfag-source/builtinModules/checks.nix':

       … while evaluating definitions from `/nix/store/qkhvhmkj14mggx578gpqw74w5h2ic6cf-source/flakelight-treefmt.nix':

       (stack trace truncated; use '--show-trace' to show the full, detailed trace)

       error: expected a set but found null: null