error:
       … while calling the 'seq' builtin
         at /pwd/lang/eval-fail-genericClosure-deeply-nested-element.nix:25:1:
           24| in
           25| builtins.seq finiteVal (
             | ^
           26|   builtins.genericClosure {

       … while calling the 'genericClosure' builtin
         at /pwd/lang/eval-fail-genericClosure-deeply-nested-element.nix:26:3:
           25| builtins.seq finiteVal (
           26|   builtins.genericClosure {
             |   ^
           27|     startSet = [

       … in genericClosure element { finite = { a0 = { a1 = { a2 = { a3 = { a4 = { a5 = { a6 = { a7 = { a8 = { ... }; }; }; }; }; }; }; }; }; }; «1 attribute elided» }

       error: attribute 'key' missing