diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index d8c73820..2342647f 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -24,6 +24,8 @@ def SimpleCov.roda_coverage(opts = {})
 
 require_relative "../lib/roda"
 require "stringio"
+
+ENV['MT_NO_PLUGINS'] = '1' # Work around stupid autoloading of plugins
 gem 'minitest'
 require "minitest/autorun"