diff --git a/actioncable/Rakefile b/actioncable/Rakefile
index bda8c7b6c8a37821137ba722ff59f4bd1201acf5..0ee1a859e5407b5e6c44f9adb5822d1eed5f8399 100644
--- a/actioncable/Rakefile
+++ b/actioncable/Rakefile
@@ -65,7 +65,7 @@ namespace :assets do
     end
 
     print "[verify] #{dir} can be required as a module "
-    stdout, stderr, status = Open3.capture3("node", "--print", "window = {}; require('#{dir}');")
+    _, stderr, status = Open3.capture3("node", "--print", "window = {}; require('#{dir}');")
     if status.success?
       puts "[OK]"
     else
diff --git a/actionview/Rakefile b/actionview/Rakefile
index de588ad25c2b9fcbecd48cb98976979ac34a079c..4f22ef84c80b2a31573b9f131a72b8299bf28060 100644
--- a/actionview/Rakefile
+++ b/actionview/Rakefile
@@ -119,7 +119,7 @@ namespace :assets do
       class Element {}
       require('#{dir}')
     JS
-    stdout, stderr, status = Open3.capture3("node", "--print", js)
+    _, stderr, status = Open3.capture3("node", "--print", js)
     if status.success?
       puts "[OK]"
     else