https://github.com/ddollar/heroku-buildpack-multi.git
https://github.com/rhy-jot/buildpack-nginx.git
https://github.com/Kloadut/heroku-buildpack-static-apache.git
https://github.com/bacongobbler/heroku-buildpack-jekyll.git
https://github.com/heroku/heroku-buildpack-ruby.git
https://github.com/heroku/heroku-buildpack-nodejs.git
https://github.com/heroku/heroku-buildpack-java.git
https://github.com/heroku/heroku-buildpack-play.git
https://github.com/heroku/heroku-buildpack-python.git
https://github.com/heroku/heroku-buildpack-scala.git
https://github.com/heroku/heroku-buildpack-clojure.git
https://github.com/heroku/heroku-buildpack-gradle.git
https://github.com/heroku/heroku-buildpack-grails.git
https://github.com/heroku/heroku-buildpack-php.git
https://github.com/heroku/heroku-buildpack-erlang.git
https://github.com/kr/heroku-buildpack-go.git
https://github.com/oortcloud/heroku-buildpack-meteorite.git
https://github.com/miyagawa/heroku-buildpack-perl.git
https://github.com/igrigorik/heroku-buildpack-dart.git

https://github.com/ddollar/heroku-buildpack-multi.git
https://github.com/rhy-jot/buildpack-nginx.git
https://github.com/bacongobbler/heroku-buildpack-jekyll.git
https://github.com/heroku/heroku-buildpack-ruby.git
https://github.com/heroku/heroku-buildpack-nodejs.git
https://github.com/heroku/heroku-buildpack-java.git
https://github.com/heroku/heroku-buildpack-play.git
https://github.com/heroku/heroku-buildpack-python.git
https://github.com/heroku/heroku-buildpack-scala.git
https://github.com/heroku/heroku-buildpack-clojure.git
https://github.com/heroku/heroku-buildpack-gradle.git
https://github.com/heroku/heroku-buildpack-grails.git
https://github.com/heroku/heroku-buildpack-php.git
https://github.com/heroku/heroku-buildpack-erlang.git
https://github.com/kr/heroku-buildpack-go.git
https://github.com/oortcloud/heroku-buildpack-meteorite.git
https://github.com/miyagawa/heroku-buildpack-perl.git
https://github.com/igrigorik/heroku-buildpack-dart.git
https://github.com/Kloadut/heroku-buildpack-static-apache.git

Move static apache at the end of the list
Move static apache at the end of the list

It's detected by the presence of .htaccess which is pretty common to many kind of apps.