title: rake assets:precompile not working on heroku - foundation and heroku failing
body: <p>I already tried different versions of rails-sass but this did not help.</p>
  
  <p>Rails with Foundation fail to upload on Heroku:
  Precompiling assets failed.</p>
  
  <p>Any suggestions on how to resolve this?
  Bootstap is also giving me the same error....        </p>
  
  <pre><code>marc@marc-ThinkPad-W510:~/Projects/provisionen2$ git push heroku master
      Counting objects: 81, done.
      Delta compression using up to 8 threads.
      Compressing objects: 100% (57/57), done.
      Writing objects: 100% (60/60), 55.95 KiB | 0 bytes/s, done.
      Total 60 (delta 36), reused 0 (delta 0)
      remote: Compressing source files... done.
      remote: Building source:
      remote: 
      remote: -----&gt; Ruby app detected
      remote: -----&gt; Compiling Ruby/Rails
      remote: -----&gt; Using Ruby version: ruby-2.0.0
      remote: -----&gt; Installing dependencies using 1.9.7
      remote:        Running: bundle install --without development:test --path vendor/bundle --binstubs vendor/bundle/bin -j4 --deployment
      remote:        Rubygems 2.0.14 is not threadsafe, so your gems must be installed one at a time. Upgrade to Rubygems 2.1.0 or higher to enable parallel gem installation.
      remote:        Using rake 10.4.2
      remote:        Using i18n 0.7.0
      remote:        Using json 1.8.3
      remote:        Using minitest 5.7.0
      remote:        Using thread_safe 0.3.5
      remote:        Using tzinfo 1.2.2
      remote:        Using activesupport 4.2.0
      remote:        Using builder 3.2.2
      remote:        Using erubis 2.7.0
      remote:        Using mini_portile 0.6.2
      remote:        Using nokogiri 1.6.6.2
      remote:        Using rails-deprecated_sanitizer 1.0.3
      remote:        Using rails-dom-testing 1.0.6
      remote:        Using loofah 2.0.2
      remote:        Using rails-html-sanitizer 1.0.2
      remote:        Using actionview 4.2.0
      remote:        Using rack 1.6.4
      remote:        Using rack-test 0.6.3
      remote:        Using actionpack 4.2.0
      remote:        Using globalid 0.3.5
      remote:        Using activejob 4.2.0
      remote:        Using mime-types 2.6.1
      remote:        Using mail 2.6.3
      remote:        Using actionmailer 4.2.0
      remote:        Using activemodel 4.2.0
      remote:        Using arel 6.0.0
      remote:        Using activerecord 4.2.0
      remote:        Using coffee-script-source 1.9.1.1
      remote:        Using execjs 2.5.2
      remote:        Using coffee-script 2.4.1
      remote:        Using thor 0.19.1
      remote:        Using railties 4.2.0
      remote:        Using coffee-rails 4.1.0
      remote:        Using multi_json 1.11.1
      remote:        Using jbuilder 2.3.0
      remote:        Using jquery-rails 4.0.4
      remote:        Using pg 0.18.2
      remote:        Using bundler 1.9.7
      remote:        Using sprockets 3.2.0
      remote:        Using sprockets-rails 2.3.1
      remote:        Using rails 4.2.0
      remote:        Using rdoc 4.2.0
      remote:        Using sass 3.4.15
      remote:        Using tilt 1.4.1
      remote:        Using sass-rails 5.0.3
      remote:        Using sdoc 0.4.1
      remote:        Using turbolinks 2.5.3
      remote:        Using uglifier 2.7.1
      remote:        Bundle complete! 13 Gemfile dependencies, 48 gems now installed.
      remote:        Gems in the groups development and test were not installed.
      remote:        Bundled gems are installed into ./vendor/bundle.
      remote:        Bundle completed (0.59s)
      remote:        Cleaning up the bundler cache.
      remote: -----&gt; Preparing app for Rails asset pipeline
      remote:        Running: rake assets:precompile
      remote:        rake aborted!
      remote:        Sprockets::FileNotFound: couldn't find file 'foundation' with type 'application/javascript'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/app/assets/javascripts/application.js:15
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/resolve.rb:64:in `resolve!'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/directive_processor.rb:399:in `resolve'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/directive_processor.rb:207:in `process_require_directive'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/directive_processor.rb:180:in `block in process_directives'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/directive_processor.rb:178:in `each'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/directive_processor.rb:178:in `process_directives'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/directive_processor.rb:83:in `_call'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/directive_processor.rb:68:in `call'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:75:in `call_processor'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:57:in `block in call_processors'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:56:in `reverse_each'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:56:in `call_processors'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:86:in `load_asset_by_uri'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:45:in `block in load'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:155:in `fetch_asset_from_dependency_cache'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:38:in `load'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/cached_environment.rb:20:in `block in initialize'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/cached_environment.rb:47:in `yield'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/cached_environment.rb:47:in `load'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/bundle.rb:23:in `block in call'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/utils.rb:183:in `dfs'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/bundle.rb:24:in `call'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:75:in `call_processor'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:57:in `block in call_processors'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:56:in `reverse_each'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:56:in `call_processors'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:86:in `load_asset_by_uri'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:45:in `block in load'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:155:in `fetch_asset_from_dependency_cache'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:38:in `load'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/cached_environment.rb:20:in `block in initialize'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/cached_environment.rb:47:in `yield'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/cached_environment.rb:47:in `load'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/base.rb:63:in `find_asset'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/base.rb:70:in `find_all_linked_assets'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/manifest.rb:138:in `block in find'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/legacy.rb:114:in `block (2 levels) in logical_paths'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/path_utils.rb:223:in `block in stat_tree'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/path_utils.rb:207:in `block in stat_directory'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/path_utils.rb:204:in `each'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/path_utils.rb:204:in `stat_directory'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/path_utils.rb:222:in `stat_tree'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/legacy.rb:105:in `each'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/legacy.rb:105:in `block in logical_paths'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/legacy.rb:104:in `each'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/legacy.rb:104:in `logical_paths'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/manifest.rb:136:in `find'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/manifest.rb:162:in `compile'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-rails-2.3.1/lib/sprockets/rails/task.rb:70:in `block (3 levels) in define'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/rake/sprocketstask.rb:147:in `with_logger'
      remote:        /tmp/build_f0b892a940e4d998bffcb7988f833c42/vendor/bundle/ruby/2.0.0/gems/sprockets-rails-2.3.1/lib/sprockets/rails/task.rb:69:in `block (2 levels) in define'
      remote:        Tasks: TOP =&gt; assets:precompile
      remote:        (See full trace by running task with --trace)
      remote:  !
      remote:  !     Precompiling assets failed.
      remote:  !
      remote: 
      remote:  !     Push rejected, failed to compile Ruby app
      remote: 
      remote: Verifying deploy...
      remote: 
      remote: !   Push rejected to ....
      remote: 
      To https://git.heroku.com/...
       ! [remote rejected] master -&gt; master (pre-receive hook declined)
      error: Fehler beim Versenden einiger Referenzen nach 'https://git.heroku.com/...'
  source 'https://rubygems.org'
  </code></pre>
  
  <p>My gemfile looks like this:</p>
  
  <pre><code>gem 'rails', '4.2.0'
  gem 'pg'
  gem 'sass-rails', '~&gt; 4.0'
  gem 'uglifier', '&gt;= 1.3.0'
  gem 'coffee-rails', '~&gt; 4.1.0'
  gem 'jquery-rails'
  gem 'turbolinks'
  gem 'jbuilder', '~&gt; 2.0'
  gem 'foundation-rails'
  gem 'sdoc', '~&gt; 0.4.0', group: :doc
  group :development, :test do
    gem 'byebug'
    gem 'web-console', '~&gt; 2.0'
    gem 'spring'
  end
  </code></pre>