1 files changed, 6 insertions, 0 deletions
diff --git a/src/libexpr/flake/flakeref.hh b/src/libexpr/flake/flakeref.hh
index 52bb82ddb..082dd8c26 100644
--- a/src/libexpr/flake/flakeref.hh
+++ b/src/libexpr/flake/flakeref.hh
@@ -176,6 +176,12 @@ struct FlakeRef
     bool isImmutable() const;
 
     FlakeRef baseRef() const;
+
+    bool isDirty() const
+    {
+        return std::get_if<FlakeRef::IsPath>(&data)
+            && rev == Hash(rev->type);
+    }
 };
 
 std::ostream & operator << (std::ostream & str, const FlakeRef & flakeRef);