diff --git a/lib/hide/git.rb b/lib/hide/git.rb
index b0e1843..8976944 100644
--- a/lib/hide/git.rb
+++ b/lib/hide/git.rb
@@ -16,7 +16,7 @@ def changed_files
     end
 
     def in_repo command
-      output = %x[git --git-dir=#{@path}/.git #{command} 2>&1]
+      output = %x[unset GIT_DIR && git --git-dir=#{@path}/.git #{command} 2>&1]
       raise GitError, output unless $?.success?
       output
     end