title: How to avoid asking the clients to clear browser cache for the latest Javascript changes?
body: <p>A client would report a bug in our JS-heavy app, we fixed it, but the client's browser still using the cached copy.  This happens a lot, and asking our clients to flush their browser cache seems very low-tech and troublesome.</p>
  
  <p>We are aware of the <code>?ver=xxx</code> workaround, but we use <a href="http://requirejs.org/" rel="nofollow">RequireJS</a> so it's not easy to apply such hack.</p>
  
  <p>Would HTTP cache control work?  However, we noticed IIS does not pick up the JS file changes right away and the HTTP header (last modified) does not reflect the latest changes.  </p>
  
  <p>Would ETag work better?  Is it better or worse then last modified on IIS?</p>
  
  <p>Any other solutions? Thanks</p>