diff --git a/Library/Homebrew/dev-cmd/pull.rb b/Library/Homebrew/dev-cmd/pull.rb
index 7746e4db30b20..9a0af4e5cb6b0 100644
--- a/Library/Homebrew/dev-cmd/pull.rb
+++ b/Library/Homebrew/dev-cmd/pull.rb
@@ -340,6 +340,15 @@ def apply_patch
       patch_args << "-3"
       patch_args << patchpath
 
+      # git am sometimes needs GIT_COMMITTER_EMAIL to be set
+      # https://github.com/Homebrew/homebrew-test-bot/issues/131
+      if ENV["HOMEBREW_GIT_NAME"]
+        ENV["GIT_COMMITTER_NAME"] = ENV["HOMEBREW_GIT_NAME"]
+      end
+      if ENV["HOMEBREW_GIT_EMAIL"]
+        ENV["GIT_COMMITTER_EMAIL"] = ENV["HOMEBREW_GIT_EMAIL"]
+      end
+
       begin
         safe_system "git", "am", *patch_args
       rescue ErrorDuringExecution