diff --git a/eve_online.gemspec b/eve_online.gemspec
index 4d2b5e6e..3b06afd7 100644
--- a/eve_online.gemspec
+++ b/eve_online.gemspec
@@ -35,6 +35,7 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency "webmock"
   spec.add_development_dependency "vcr"
 
+  spec.add_runtime_dependency "base64"
   spec.add_runtime_dependency "faraday", ">= 2.3.0"
   spec.add_runtime_dependency "activesupport", ">= 6.1.0"
 end