anchor.diff:  java -cp "cljs.jar;src" -m cljs.main -s
   ----
   
  -`-s` is for `--serve`. This command does not start REPL, so a browser window will not be automatically
  -opened. Navigate to http://localhost:9000 using your favorite browser. Check the
  -JavaScript Console, you should see `Hello world!` printed. The build in web
  -server gzips JavaScript. Check your browser network tab and you should be able
  -to confirm that the total JavaScript payload is now around 20K.
  +`-s` is for `--serve`. This command does not start REPL, so a browser window
  +will not be automatically opened. Navigate to http://localhost:9000 using your
  +favorite browser. Check the JavaScript Console, you should see `Hello world!`
  +printed. The builtin web server gzips JavaScript. Check your browser's
  +JavaScript Console Network tab and you should be able to confirm that the total
  +JavaScript payload is now around 20K.
   
   [[running-clojurescript-on-node.js]]
   == Running ClojureScript on Node.js
  
positive.code: ----
  
  Let's build your Node project. We can specify that we want to generate code for
  a specific JavaScript target via `-t` for `--target`. `-t` defaults to browser.
  Other valid but less common options are `nashorn` and `rhino`. We're also using
  `-o` for specifying the `--output-to` file:
  
  [source,bash]
  ----
  
negative.code: == Production Builds
  
  You may have noticed the `out` directory which contains all of the compiled
  JavaScript. There's about 6 1/2 megabytes worth of JavaScript in there. This may
  seem unweildy but fortunately the ClojureScript compiler generates output
  optimized for the Google Closure Compiler. The Google Closure Compiler performs
  many optimizations, but the most significant for browser-based clients are
  minification and dead code elimination.
  
  Let's remove the dev time REPL bits from `src/hello_world/core.cljs`:
  
  