diff --git a/safe_yaml.gemspec b/safe_yaml.gemspec
index 4f4432a..a180527 100644
--- a/safe_yaml.gemspec
+++ b/safe_yaml.gemspec
@@ -16,4 +16,6 @@ Gem::Specification.new do |gem|
   gem.executables   = ["safe_yaml"]
 
   gem.required_ruby_version = ">= 1.8.7"
+
+  gem.add_dependency("base64")
 end