diff --git a/pkgs/development/ruby-modules/gem-config/default.nix b/pkgs/development/ruby-modules/gem-config/default.nix
index bf1f9d14b776..6647d71bd006 100644
--- a/pkgs/development/ruby-modules/gem-config/default.nix
+++ b/pkgs/development/ruby-modules/gem-config/default.nix
@@ -67,6 +67,10 @@ in
   charlock_holmes = attrs: {
     buildInputs = [ which icu zlib ];
   };
+  
+  curb = attrs: {
+    buildInputs = [ curl ];
+  };
 
   dep-selector-libgecode = attrs: {
     USE_SYSTEM_GECODE = true;