diff --git a/windows12.cabal b/windows12.cabal
index 4dcb859..d909179 100644
--- a/windows12.cabal
+++ b/windows12.cabal
@@ -81,6 +81,7 @@ executable windows12
         text >= 1.2.5 && < 1.3,
         parser-combinators >= 1.3.0 && < 1.4,
         prettyprinter >= 1.5.1 && < 1.6,
+        string-conversions >= 0.4.0 && < 0.5
 
     -- Directories containing source files.
     hs-source-dirs:   src