diff --git a/src/libutil/mounted-source-accessor.cc b/src/libutil/mounted-source-accessor.cc
index 45c8adbd8..97e5f10a4 100644
--- a/src/libutil/mounted-source-accessor.cc
+++ b/src/libutil/mounted-source-accessor.cc
@@ -23,12 +23,6 @@ struct MountedSourceAccessor : SourceAccessor
         return accessor->readFile(subpath);
     }
 
-    bool pathExists(const CanonPath & path) override
-    {
-        auto [accessor, subpath] = resolve(path);
-        return accessor->pathExists(subpath);
-    }
-
     std::optional<Stat> maybeLstat(const CanonPath & path) override
     {
         auto [accessor, subpath] = resolve(path);