diff --git a/Library/Homebrew/Gemfile.lock b/Library/Homebrew/Gemfile.lock
index afed0421ac..0d591ca9dd 100644
--- a/Library/Homebrew/Gemfile.lock
+++ b/Library/Homebrew/Gemfile.lock
@@ -66,7 +66,7 @@ GEM
     nokogiri (1.11.7)
       mini_portile2 (~> 2.5.0)
       racc (~> 1.4)
-    parallel (1.20.1)
+    parallel (1.21.0)
     parallel_tests (3.7.1)
       parallel
     parlour (6.0.1)