       ).join('')
       contents = sqwish.minify contents if @mode is 'production'
       fingerprint = '-' + fingerprintForPkg('css', pkg)
-      filename = "#{pkg}.css"
+      filename = "#{pkg}-#{ts}.css"
       writeFile filename, contents, (err) =>
         if @gzip then gzipPkg(contents, filename, callback) else callback()
         total++

      contents = (contents for fn, contents of preprocessPkg pkg, 'js').join(';\n')
      contents = uglify contents if @mode is 'production' and @minify
      fingerprint = '-' + fingerprintForPkg('js', pkg)
      filename = "#{pkg}.js"
      writeFile filename, contents, (err) =>
        if @gzip then gzipPkg(contents, filename, callback) else callback()
        total++

      contents = @_tmplPrefix + contents
      contents = uglify contents if @mode is 'production' and @minify
      fingerprint = '-' + fingerprintForPkg('jst', pkg)
      filename = "#{pkg}-#{ts}.jst.js"
      writeFile filename , contents, (err) =>
        if @gzip then gzipPkg(contents, filename, callback) else callback()
        total++
