diff --git a/safe-decimal.cabal b/safe-decimal.cabal
index b32600f..ea325e5 100644
--- a/safe-decimal.cabal
+++ b/safe-decimal.cabal
@@ -34,6 +34,7 @@ test-suite tests
   other-modules: Numeric.DecimalSpec
   hs-source-dirs: tests
   ghc-options: -threaded -rtsopts -with-rtsopts=-N
+  build-tool-depends: hspec-discover:hspec-discover
   build-depends: base >=4.7 && <5
                , deepseq
                , safe-decimal