Nice ! That should solve the issue where all gems are re-installed whenever the Gemfile.lock is changed. I agree that bundler is mainly focusing on the user in

Nice ! That should solve the issue where all gems are re-installed whenever the Gemfile.lock is changed. I agree that bundler is mainly focusing on the user interactions and is good at that but never look inside. I'm not even sure if the dependency resolution mechanism can be used as a library. In my opinion bundler should only be used as a dependency-resolution manager. Once gems are installed then they should use good-ol' $LOAD_PATH. Unfortunately there are the git gems and also rails which insists on using bundler. EDIT: got any thought on adding system dependencies per gem ?