diff --git a/test/test_helper.rb b/test/test_helper.rb
index d48cc729..104444c7 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -3,6 +3,7 @@
 gem "minitest"
 require "minitest/autorun"
 
+$HTTPX_DEBUG = !!ENV["HTTPX_DEBUG"]
 
 require "httpx"