--- a/ed25519.cabal
+++ b/ed25519.cabal
@@ -129,7 +129,7 @@
     build-depends:
       base      >= 4    && < 5,
       filepath  >= 1.0  && < 1.5,
-      directory >= 1.0  && < 1.3,
+      directory >= 1.0  && < 1.4,
       doctest   >= 0.10 && < 0.12
 
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