diff --git a/pkgs/development/interpreters/ruby/default.nix b/pkgs/development/interpreters/ruby/default.nix
index 8db9dd4eaf9a..446013faafdc 100644
--- a/pkgs/development/interpreters/ruby/default.nix
+++ b/pkgs/development/interpreters/ruby/default.nix
@@ -22,6 +22,7 @@ let
       then version
       else versionNoPatch;
     tag = "v" + stdenv.lib.replaceChars ["." "p" "-"] ["_" "_" ""] fullVersionName;
+    isRuby20 = majorVersion == "2" && minorVersion == "0";
     isRuby21 = majorVersion == "2" && minorVersion == "1";
     baseruby = self.override { useRailsExpress = false; };
     self = lib.makeOverridable (
@@ -81,6 +82,8 @@ let
 
         enableParallelBuilding = true;
 
+        hardeningDisable = lib.optional isRuby20 [ "format" ];
+
         patches =
           [ ./gem_hook.patch ] ++
           (import ./patchsets.nix {