Step 1: Install MIT Scheme.
Step 2: Grab GNU Emacs and Get Scheme REPL to run in Emacs. Pay attention to your specific Scheme app path with the latter setup.
Step 3: Configure autocomplete. As of 2015, link to the latest version should be http://cx4a.org/pub/auto-complete/auto-complete-1.3.1.tar.bz2
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