diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh
index 4ed2fd151..4fb6c40c7 100644
--- a/src/libstore/store-api.hh
+++ b/src/libstore/store-api.hh
@@ -683,7 +683,7 @@ public:
        the Nix store. Optionally, the contents of the NARs are
        preloaded into the specified FS accessor to speed up subsequent
        access. */
-    virtual StorePaths importPaths(Source & source, CheckSigsFlag checkSigs = CheckSigs);
+    StorePaths importPaths(Source & source, CheckSigsFlag checkSigs = CheckSigs);
 
     struct Stats
     {