diff --git a/tests/functional/flakes/flakes.sh b/tests/functional/flakes/flakes.sh
index 78ad833e5..611e8626d 100755
--- a/tests/functional/flakes/flakes.sh
+++ b/tests/functional/flakes/flakes.sh
@@ -76,7 +76,7 @@ hash1=$(echo "$json" | jq -r .revision)
 echo foo > "$flake1Dir/foo"
 git -C "$flake1Dir" add $flake1Dir/foo
 [[ $(nix flake metadata flake1 --json --refresh | jq -r .dirtyRevision) == "$hash1-dirty" ]]
-#[[ $(_NIX_TEST_FAIL_ON_LARGE_PATH=1 nix flake metadata flake1 --json --refresh --warn-large-path-threshold 1 | jq -r .dirtyRevision) == "$hash1-dirty" ]]
+[[ $(_NIX_TEST_FAIL_ON_LARGE_PATH=1 nix flake metadata flake1 --json --refresh --warn-large-path-threshold 1 --lazy-trees | jq -r .dirtyRevision) == "$hash1-dirty" ]]
 [[ "$(nix flake metadata flake1 --json | jq -r .fingerprint)" != null ]]
 
 echo -n '# foo' >> "$flake1Dir/flake.nix"
diff --git a/tests/functional/flakes/unlocked-override.sh b/tests/functional/flakes/unlocked-override.sh
index 73784b4e8..bd73929dc 100755
--- a/tests/functional/flakes/unlocked-override.sh
+++ b/tests/functional/flakes/unlocked-override.sh
@@ -36,7 +36,7 @@ expectStderr 1 nix flake lock "$flake2Dir" --override-input flake1 "$TEST_ROOT/f
   grepQuiet "Will not write lock file.*because it has an unlocked input"
 
 nix flake lock "$flake2Dir" --override-input flake1 "$TEST_ROOT/flake1" --allow-dirty-locks
-#_NIX_TEST_FAIL_ON_LARGE_PATH=1 nix flake lock "$flake2Dir" --override-input flake1 "$TEST_ROOT/flake1" --allow-dirty-locks --warn-large-path-threshold 1
+_NIX_TEST_FAIL_ON_LARGE_PATH=1 nix flake lock "$flake2Dir" --override-input flake1 "$TEST_ROOT/flake1" --allow-dirty-locks --warn-large-path-threshold 1 --lazy-trees
 
 # Using a lock file with a dirty lock does not require --allow-dirty-locks, but should print a warning.
 expectStderr 0 nix eval "$flake2Dir#x" |