diff --git a/lib/tailwindcss/upstream.rb b/lib/tailwindcss/upstream.rb
index def45f35..d31ee9f8 100644
--- a/lib/tailwindcss/upstream.rb
+++ b/lib/tailwindcss/upstream.rb
@@ -6,6 +6,7 @@ module Upstream
     # rubygems platform name => upstream release filename
     NATIVE_PLATFORMS = {
       "arm64-darwin" => "tailwindcss-macos-arm64",
+      "arm64-darwin-21" => "tailwindcss-macos-arm64",
       "x64-mingw32" => "tailwindcss-windows-x64.exe",
       "x86_64-darwin" => "tailwindcss-macos-x64",
       "x86_64-linux" => "tailwindcss-linux-x64",