diff --git a/pkgs/top-level/haskell-packages.nix b/pkgs/top-level/haskell-packages.nix
index 372b5d34acb..90b7385147d 100644
--- a/pkgs/top-level/haskell-packages.nix
+++ b/pkgs/top-level/haskell-packages.nix
@@ -1250,7 +1250,7 @@ let result = let callPackage = x : y : modifyPrio (newScope result.final x y);
 
   OpenGLRaw = callPackage ../development/libraries/haskell/OpenGLRaw {};
 
-  optparse_applicative = callPackage ../development/libraries/haskell/optparse-applicative {};
+  optparseApplicative = callPackage ../development/libraries/haskell/optparse-applicative {};
 
   pathPieces = callPackage ../development/libraries/haskell/path-pieces {};