diff --git a/rubygem-rack-test.spec b/rubygem-rack-test.spec
index 3d45165..acf1998 100644
--- a/rubygem-rack-test.spec
+++ b/rubygem-rack-test.spec
@@ -17,6 +17,7 @@ BuildRequires:  rubygems
 BuildRequires:  rubygem(rack) >= 0.9.1
 BuildRequires:  rubygem(rake)
 BuildRequires:  rubygem(rspec)
+BuildRequires:  rubygem(sinatra)
 BuildArch:      noarch
 Provides:       rubygem(%{gemname}) = %{version}