diff --git a/Guardfile b/Guardfile
index 383c5b1..23bed63 100644
--- a/Guardfile
+++ b/Guardfile
@@ -26,6 +26,8 @@ group :rspec do
     watch(%r{^spec/helpers/.+\.rb$})       { all_specs }
     watch(%r{^spec/fixtures/.+\.rb$})      { all_specs }
     watch(%r{^libraries/pacemaker\.rb$})   { all_specs }
+    watch(%r{^libraries/pacemaker/[^/]+\.rb$}) \
+                                           { all_specs }
     watch(%r{^libraries/(.*mixin.*)\.rb$}) { all_specs }
     watch(%r{^(spec/.+_spec\.rb)$})        { |m| reload m[1] }
     watch(%r{^libraries/(.+)\.rb$})  { |m|