diff --git a/tests/functional2/lang/callable-attrs/eval-okay.out.exp b/tests/functional2/lang/__functor/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/callable-attrs/eval-okay.out.exp rename to tests/functional2/lang/__functor/eval-okay.out.exp diff --git a/tests/functional2/lang/callable-attrs/in.nix b/tests/functional2/lang/__functor/in.nix similarity index 100% rename from tests/functional2/lang/callable-attrs/in.nix rename to tests/functional2/lang/__functor/in.nix diff --git a/tests/functional2/lang/abort/eval-fail.err.exp b/tests/functional2/lang/builtins.abort/eval-fail.err.exp similarity index 100% rename from tests/functional2/lang/abort/eval-fail.err.exp rename to tests/functional2/lang/builtins.abort/eval-fail.err.exp diff --git a/tests/functional2/lang/abort/in.nix b/tests/functional2/lang/builtins.abort/in.nix similarity index 100% rename from tests/functional2/lang/abort/in.nix rename to tests/functional2/lang/builtins.abort/in.nix diff --git a/tests/functional2/lang/any-all/eval-okay.out.exp b/tests/functional2/lang/builtins.any-all/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/any-all/eval-okay.out.exp rename to tests/functional2/lang/builtins.any-all/eval-okay.out.exp diff --git a/tests/functional2/lang/any-all/in.nix b/tests/functional2/lang/builtins.any-all/in.nix similarity index 100% rename from tests/functional2/lang/any-all/in.nix rename to tests/functional2/lang/builtins.any-all/in.nix diff --git a/tests/functional2/lang/attrnames/eval-okay.out.exp b/tests/functional2/lang/builtins.attrNames-getAttr-attrValues/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/attrnames/eval-okay.out.exp rename to tests/functional2/lang/builtins.attrNames-getAttr-attrValues/eval-okay.out.exp diff --git a/tests/functional2/lang/attrnames/in.nix b/tests/functional2/lang/builtins.attrNames-getAttr-attrValues/in.nix similarity index 100% rename from tests/functional2/lang/attrnames/in.nix rename to tests/functional2/lang/builtins.attrNames-getAttr-attrValues/in.nix diff --git a/tests/functional2/lang/catattrs/eval-okay.out.exp b/tests/functional2/lang/builtins.catAttrs/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/catattrs/eval-okay.out.exp rename to tests/functional2/lang/builtins.catAttrs/eval-okay.out.exp diff --git a/tests/functional2/lang/catattrs/in.nix b/tests/functional2/lang/builtins.catAttrs/in.nix similarity index 100% rename from tests/functional2/lang/catattrs/in.nix rename to tests/functional2/lang/builtins.catAttrs/in.nix diff --git a/tests/functional2/lang/concatmap/eval-okay.out.exp b/tests/functional2/lang/builtins.concatMap/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/concatmap/eval-okay.out.exp rename to tests/functional2/lang/builtins.concatMap/eval-okay.out.exp diff --git a/tests/functional2/lang/concatmap/in.nix b/tests/functional2/lang/builtins.concatMap/in.nix similarity index 100% rename from tests/functional2/lang/concatmap/in.nix rename to tests/functional2/lang/builtins.concatMap/in.nix diff --git a/tests/functional2/lang/concatstringssep/eval-okay.out.exp b/tests/functional2/lang/builtins.concatStringsSep/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/concatstringssep/eval-okay.out.exp rename to tests/functional2/lang/builtins.concatStringsSep/eval-okay.out.exp diff --git a/tests/functional2/lang/concatstringssep/in.nix b/tests/functional2/lang/builtins.concatStringsSep/in.nix similarity index 100% rename from tests/functional2/lang/concatstringssep/in.nix rename to tests/functional2/lang/builtins.concatStringsSep/in.nix diff --git a/tests/functional2/lang/deepseq/eval-fail.err.exp b/tests/functional2/lang/builtins.deepSeq/eval-fail.err.exp similarity index 100% rename from tests/functional2/lang/deepseq/eval-fail.err.exp rename to tests/functional2/lang/builtins.deepSeq/eval-fail.err.exp diff --git a/tests/functional2/lang/deepseq/in.nix b/tests/functional2/lang/builtins.deepSeq/in.nix similarity index 100% rename from tests/functional2/lang/deepseq/in.nix rename to tests/functional2/lang/builtins.deepSeq/in.nix diff --git a/tests/functional2/lang/elem/eval-okay.out.exp b/tests/functional2/lang/builtins.elem/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/elem/eval-okay.out.exp rename to tests/functional2/lang/builtins.elem/eval-okay.out.exp diff --git a/tests/functional2/lang/elem/in.nix b/tests/functional2/lang/builtins.elem/in.nix similarity index 100% rename from tests/functional2/lang/elem/in.nix rename to tests/functional2/lang/builtins.elem/in.nix diff --git a/tests/functional2/lang/filter/eval-okay.out.exp b/tests/functional2/lang/builtins.filter/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/filter/eval-okay.out.exp rename to tests/functional2/lang/builtins.filter/eval-okay.out.exp diff --git a/tests/functional2/lang/filter/in.nix b/tests/functional2/lang/builtins.filter/in.nix similarity index 100% rename from tests/functional2/lang/filter/in.nix rename to tests/functional2/lang/builtins.filter/in.nix diff --git a/tests/functional2/lang/floor-ceil/eval-okay.out.exp b/tests/functional2/lang/builtins.floor-ceil/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/floor-ceil/eval-okay.out.exp rename to tests/functional2/lang/builtins.floor-ceil/eval-okay.out.exp diff --git a/tests/functional2/lang/floor-ceil/in.nix b/tests/functional2/lang/builtins.floor-ceil/in.nix similarity index 100% rename from tests/functional2/lang/floor-ceil/in.nix rename to tests/functional2/lang/builtins.floor-ceil/in.nix diff --git a/tests/functional2/lang/groupBy/eval-okay.out.exp b/tests/functional2/lang/builtins.groupBy/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/groupBy/eval-okay.out.exp rename to tests/functional2/lang/builtins.groupBy/eval-okay.out.exp diff --git a/tests/functional2/lang/groupBy/in.nix b/tests/functional2/lang/builtins.groupBy/in.nix similarity index 100% rename from tests/functional2/lang/groupBy/in.nix rename to tests/functional2/lang/builtins.groupBy/in.nix diff --git a/tests/functional2/lang/hashstring/eval-okay.out.exp b/tests/functional2/lang/builtins.hashString/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/hashstring/eval-okay.out.exp rename to tests/functional2/lang/builtins.hashString/eval-okay.out.exp diff --git a/tests/functional2/lang/hashstring/in.nix b/tests/functional2/lang/builtins.hashString/in.nix similarity index 100% rename from tests/functional2/lang/hashstring/in.nix rename to tests/functional2/lang/builtins.hashString/in.nix diff --git a/tests/functional2/lang/intersectAttrs/eval-okay.out.exp b/tests/functional2/lang/builtins.intersectAttrs/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/intersectAttrs/eval-okay.out.exp rename to tests/functional2/lang/builtins.intersectAttrs/eval-okay.out.exp diff --git a/tests/functional2/lang/intersectAttrs/in.nix b/tests/functional2/lang/builtins.intersectAttrs/in.nix similarity index 100% rename from tests/functional2/lang/intersectAttrs/in.nix rename to tests/functional2/lang/builtins.intersectAttrs/in.nix diff --git a/tests/functional2/lang/listtoattrs/eval-okay.out.exp b/tests/functional2/lang/builtins.listToAttrs/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/listtoattrs/eval-okay.out.exp rename to tests/functional2/lang/builtins.listToAttrs/eval-okay.out.exp diff --git a/tests/functional2/lang/listtoattrs/in.nix b/tests/functional2/lang/builtins.listToAttrs/in.nix similarity index 100% rename from tests/functional2/lang/listtoattrs/in.nix rename to tests/functional2/lang/builtins.listToAttrs/in.nix diff --git a/tests/functional2/lang/map/eval-okay.out.exp b/tests/functional2/lang/builtins.map/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/map/eval-okay.out.exp rename to tests/functional2/lang/builtins.map/eval-okay.out.exp diff --git a/tests/functional2/lang/map/in.nix b/tests/functional2/lang/builtins.map/in.nix similarity index 100% rename from tests/functional2/lang/map/in.nix rename to tests/functional2/lang/builtins.map/in.nix diff --git a/tests/functional2/lang/mapattrs/eval-okay.out.exp b/tests/functional2/lang/builtins.mapAttrs/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/mapattrs/eval-okay.out.exp rename to tests/functional2/lang/builtins.mapAttrs/eval-okay.out.exp diff --git a/tests/functional2/lang/mapattrs/in.nix b/tests/functional2/lang/builtins.mapAttrs/in.nix similarity index 100% rename from tests/functional2/lang/mapattrs/in.nix rename to tests/functional2/lang/builtins.mapAttrs/in.nix diff --git a/tests/functional2/lang/regex-match/eval-okay.out.exp b/tests/functional2/lang/builtins.matches/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/regex-match/eval-okay.out.exp rename to tests/functional2/lang/builtins.matches/eval-okay.out.exp diff --git a/tests/functional2/lang/regex-match/in.nix b/tests/functional2/lang/builtins.matches/in.nix similarity index 100% rename from tests/functional2/lang/regex-match/in.nix rename to tests/functional2/lang/builtins.matches/in.nix diff --git a/tests/functional2/lang/parse-flake-ref/eval-okay.out.exp b/tests/functional2/lang/builtins.parseFlakeRef/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/parse-flake-ref/eval-okay.out.exp rename to tests/functional2/lang/builtins.parseFlakeRef/eval-okay.out.exp diff --git a/tests/functional2/lang/parse-flake-ref/in.nix b/tests/functional2/lang/builtins.parseFlakeRef/in.nix similarity index 100% rename from tests/functional2/lang/parse-flake-ref/in.nix rename to tests/functional2/lang/builtins.parseFlakeRef/in.nix diff --git a/tests/functional2/lang/partition/eval-okay.out.exp b/tests/functional2/lang/builtins.partition/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/partition/eval-okay.out.exp rename to tests/functional2/lang/builtins.partition/eval-okay.out.exp diff --git a/tests/functional2/lang/partition/in.nix b/tests/functional2/lang/builtins.partition/in.nix similarity index 100% rename from tests/functional2/lang/partition/in.nix rename to tests/functional2/lang/builtins.partition/in.nix diff --git a/tests/functional2/lang/remove/eval-fail.err.exp b/tests/functional2/lang/builtins.removeAttrs/eval-fail.err.exp similarity index 100% rename from tests/functional2/lang/remove/eval-fail.err.exp rename to tests/functional2/lang/builtins.removeAttrs/eval-fail.err.exp diff --git a/tests/functional2/lang/remove/in.nix b/tests/functional2/lang/builtins.removeAttrs/in.nix similarity index 100% rename from tests/functional2/lang/remove/in.nix rename to tests/functional2/lang/builtins.removeAttrs/in.nix diff --git a/tests/functional2/lang/replacestrings/eval-okay.out.exp b/tests/functional2/lang/builtins.replaceStrings/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/replacestrings/eval-okay.out.exp rename to tests/functional2/lang/builtins.replaceStrings/eval-okay.out.exp diff --git a/tests/functional2/lang/replacestrings/in.nix b/tests/functional2/lang/builtins.replaceStrings/in.nix similarity index 100% rename from tests/functional2/lang/replacestrings/in.nix rename to tests/functional2/lang/builtins.replaceStrings/in.nix diff --git a/tests/functional2/lang/seq/eval-fail.err.exp b/tests/functional2/lang/builtins.seq/eval-fail.err.exp similarity index 100% rename from tests/functional2/lang/seq/eval-fail.err.exp rename to tests/functional2/lang/builtins.seq/eval-fail.err.exp diff --git a/tests/functional2/lang/seq/in.nix b/tests/functional2/lang/builtins.seq/in.nix similarity index 100% rename from tests/functional2/lang/seq/in.nix rename to tests/functional2/lang/builtins.seq/in.nix diff --git a/tests/functional2/lang/sort/eval-okay.out.exp b/tests/functional2/lang/builtins.sort/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/sort/eval-okay.out.exp rename to tests/functional2/lang/builtins.sort/eval-okay.out.exp diff --git a/tests/functional2/lang/sort/in.nix b/tests/functional2/lang/builtins.sort/in.nix similarity index 100% rename from tests/functional2/lang/sort/in.nix rename to tests/functional2/lang/builtins.sort/in.nix diff --git a/tests/functional2/lang/regex-split/eval-okay.out.exp b/tests/functional2/lang/builtins.split/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/regex-split/eval-okay.out.exp rename to tests/functional2/lang/builtins.split/eval-okay.out.exp diff --git a/tests/functional2/lang/regex-split/in.nix b/tests/functional2/lang/builtins.split/in.nix similarity index 100% rename from tests/functional2/lang/regex-split/in.nix rename to tests/functional2/lang/builtins.split/in.nix diff --git a/tests/functional2/lang/splitversion/eval-okay.out.exp b/tests/functional2/lang/builtins.splitVersion/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/splitversion/eval-okay.out.exp rename to tests/functional2/lang/builtins.splitVersion/eval-okay.out.exp diff --git a/tests/functional2/lang/splitversion/in.nix b/tests/functional2/lang/builtins.splitVersion/in.nix similarity index 100% rename from tests/functional2/lang/splitversion/in.nix rename to tests/functional2/lang/builtins.splitVersion/in.nix diff --git a/tests/functional2/lang/substring/eval-fail.err.exp b/tests/functional2/lang/builtins.substring/eval-fail.err.exp similarity index 100% rename from tests/functional2/lang/substring/eval-fail.err.exp rename to 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tests/functional2/lang/toString/eval-fail.err.exp rename to tests/functional2/lang/builtins.toString/eval-fail.err.exp diff --git a/tests/functional2/lang/toString/in.nix b/tests/functional2/lang/builtins.toString/in.nix similarity index 100% rename from tests/functional2/lang/toString/in.nix rename to tests/functional2/lang/builtins.toString/in.nix diff --git a/tests/functional2/lang/tryeval/eval-okay.out.exp b/tests/functional2/lang/builtins.tryEval/eval-okay.out.exp similarity index 100% rename from tests/functional2/lang/tryeval/eval-okay.out.exp rename to tests/functional2/lang/builtins.tryEval/eval-okay.out.exp diff --git a/tests/functional2/lang/tryeval/in.nix b/tests/functional2/lang/builtins.tryEval/in.nix similarity index 100% rename from tests/functional2/lang/tryeval/in.nix rename to tests/functional2/lang/builtins.tryEval/in.nix diff --git a/tests/functional2/lang/zipAttrsWith/eval-okay.out.exp b/tests/functional2/lang/builtins.zipAttrsWith/eval-okay.out.exp similarity 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from tests/functional2/lang/json/in.nix rename to tests/functional2/lang/parser-output-json/in.nix diff --git a/tests/functional2/lang/json/parse-okay.out.exp b/tests/functional2/lang/parser-output-json/parse-okay.out.exp similarity index 100% rename from tests/functional2/lang/json/parse-okay.out.exp rename to tests/functional2/lang/parser-output-json/parse-okay.out.exp