title: What to do after removing a gem from the Gemfile?
body: <p>I removed a gem 'mygem' from the Gemfile, but just now I realized it's still installed.</p>
  
  <p>So how do I tell bundler to rescan the Gemfile and update Gemfile.lock, <strong>without</strong> updating every gem?</p>
  
  <p>Coming from php, this is how I'm used to do this: <code>composer update nothing</code>. Is there an equivalent for bundler?</p>