diff --git a/src/lib/Hydra/Controller/Root.pm b/src/lib/Hydra/Controller/Root.pm
index 473892511..75d35ac3c 100644
--- a/src/lib/Hydra/Controller/Root.pm
+++ b/src/lib/Hydra/Controller/Root.pm
@@ -329,7 +329,7 @@ sub nar :Local :Args(1) {
     else {
         $path = $Nix::Config::storeDir . "/$path";
 
-        gone($c, "Path " . $path . " is no longer available.") unless isValidPath($path);
+        gone($c, "Path " . $path . " is no longer available.") unless $MACHINE_LOCAL_STORE->isValidPath($path);
 
         $c->stash->{current_view} = 'NixNAR';
         $c->stash->{storePath} = $path;
diff --git a/src/lib/Hydra/Plugin/S3Backup.pm b/src/lib/Hydra/Plugin/S3Backup.pm
index 98e797478..a0d678510 100644
--- a/src/lib/Hydra/Plugin/S3Backup.pm
+++ b/src/lib/Hydra/Plugin/S3Backup.pm
@@ -92,7 +92,7 @@ sub buildFinished {
         my $hash = substr basename($path), 0, 32;
         my ($deriver, $narHash, $time, $narSize, $refs) = queryPathInfo($path, 0);
         my $system;
-        if (defined $deriver and isValidPath($deriver)) {
+        if (defined $deriver and $MACHINE_LOCAL_STORE->isValidPath($deriver)) {
             $system = derivationFromPath($deriver)->{platform};
         }
         foreach my $reference (@{$refs}) {
diff --git a/src/lib/Hydra/Plugin/SubversionInput.pm b/src/lib/Hydra/Plugin/SubversionInput.pm
index 83c1f39d2..d3579c40f 100644
--- a/src/lib/Hydra/Plugin/SubversionInput.pm
+++ b/src/lib/Hydra/Plugin/SubversionInput.pm
@@ -46,7 +46,7 @@ sub fetchInput {
 
     $MACHINE_LOCAL_STORE->addTempRoot($cachedInput->storepath) if defined $cachedInput;
 
-    if (defined $cachedInput && isValidPath($cachedInput->storepath)) {
+    if (defined $cachedInput && $MACHINE_LOCAL_STORE->isValidPath($cachedInput->storepath)) {
         $storePath = $cachedInput->storepath;
         $sha256 = $cachedInput->sha256hash;
     } else {