title: File to import not found or unreadable: bootstrap. Heroku deploy failed
body: <p><strong>UPD:</strong> Issue solved.</p>
  
  <p>I add gem twitter-bootstrap in overall list of gems (not only group :assets). 
  And had to precompile before deploying. </p>
  
  <hr>
  
  <p>Have a problem with deploying.
  <code>application.css.scss</code> now doesn't exist - the file was removed.
  What can be the problem?
  Problems started when I was adding <code>bootstrap-sass</code> instead of <code>.less</code> version. But it failed for unknown reasons. I decided to go back and now I have these problems.</p>
  
  <pre><code>-----&gt; Preparing app for Rails asset pipeline
         Running: rake assets:precompile
         rake aborted!
         File to import not found or unreadable: bootstrap.
         Load path: Sass::Rails::Importer(/tmp/build_3es5vmj75q0ih/app/assets/stylesheets/application.css.scss)
         (in /tmp/build_3es5vmj75q0ih/app/assets/stylesheets/application.css.scss)
         /tmp/build_3es5vmj75q0ih/app/assets/stylesheets/application.css.scss:16
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/import_node.rb:67:in `rescue in import'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/import_node.rb:45:in `import'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/import_node.rb:28:in `imported_file'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/import_node.rb:37:in `css_import?'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/perform.rb:215:in `visit_import'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/base.rb:37:in `visit'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/perform.rb:98:in `visit'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/base.rb:53:in `block in visit_children'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/base.rb:53:in `map'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/base.rb:53:in `visit_children'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/perform.rb:107:in `block in visit_children'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/perform.rb:119:in `with_environment'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/perform.rb:106:in `visit_children'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/base.rb:37:in `block in visit'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/perform.rb:126:in `visit_root'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/base.rb:37:in `visit'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/perform.rb:98:in `visit'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/visitors/perform.rb:7:in `visit'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/tree/root_node.rb:20:in `render'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/engine.rb:315:in `_render'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-3.2.3/lib/sass/engine.rb:262:in `render'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sass-rails-3.2.5/lib/sass/rails/template_handlers.rb:106:in `evaluate'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/tilt-1.3.3/lib/tilt/template.rb:76:in `render'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/context.rb:177:in `block in evaluate'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/context.rb:174:in `each'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/context.rb:174:in `evaluate'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/processed_asset.rb:12:in `initialize'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:241:in `new'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:241:in `block in build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:262:in `circular_call_protection'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:240:in `build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/index.rb:89:in `block in build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/caching.rb:19:in `cache_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/index.rb:88:in `build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:163:in `find_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/index.rb:56:in `find_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/processed_asset.rb:106:in `block in build_required_assets'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/processed_asset.rb:100:in `each'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/processed_asset.rb:100:in `build_required_assets'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/processed_asset.rb:16:in `initialize'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:241:in `new'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:241:in `block in build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:262:in `circular_call_protection'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:240:in `build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/index.rb:89:in `block in build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/caching.rb:19:in `cache_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/index.rb:88:in `build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:163:in `find_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/index.rb:56:in `find_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/bundled_asset.rb:16:in `initialize'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:244:in `new'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:244:in `build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/index.rb:89:in `block in build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/caching.rb:19:in `cache_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/index.rb:88:in `build_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:163:in `find_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/index.rb:56:in `find_asset'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.2/lib/sprockets/static_compiler.rb:20:in `block in compile'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:212:in `block in each_logical_path'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:200:in `block (2 levels) in each_file'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:190:in `each'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:190:in `each_entry'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:198:in `block in each_file'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:197:in `each'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:197:in `each_file'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/sprockets-2.1.3/lib/sprockets/base.rb:210:in `each_logical_path'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.2/lib/sprockets/static_compiler.rb:18:in `compile'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.2/lib/sprockets/assets.rake:56:in `internal_precompile'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.2/lib/sprockets/assets.rake:70:in `block (3 levels) in &lt;top (required)&gt;'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.2/lib/sprockets/assets.rake:60:in `block (3 levels) in &lt;top (required)&gt;'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.2/lib/sprockets/assets.rake:23:in `invoke_or_reboot_rake_task'
         /tmp/build_3es5vmj75q0ih/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.2/lib/sprockets/assets.rake:29:in `block (2 levels) in &lt;top (required)&gt;'
         Tasks: TOP =&gt; assets:precompile:primary
         (See full trace by running task with --trace)
         Precompiling assets failed, enabling runtime asset compilation
         Injecting rails31_enable_runtime_asset_compilation
         Please see this article for troubleshooting help:
         http://devcenter.heroku.com/articles/rails31_heroku_cedar#troubleshooting
  -----&gt; Rails plugin injection
         Injecting rails_log_stdout
         Injecting rails3_serve_static_assets
  -----&gt; Discovering process types
         Procfile declares types      -&gt; (none)
         Default types for Ruby/Rails -&gt; console, rake, web, worker
  -----&gt; Compiled slug size: 15.9MB
  -----&gt; Launching... done, v14
  </code></pre>
  
  <p>And in <strong>Heroku</strong> logs I have that:</p>
  
  <pre><code>2012-11-23T01:34:01+00:00 app[web.1]: =&gt; Rails 3.2.2 application starting in production on http://0.0.0.0:4868
  2012-11-23T01:34:01+00:00 app[web.1]: =&gt; Call with -d to detach
  2012-11-23T01:34:01+00:00 app[web.1]: Processing by SearchesController#new as HTML
  2012-11-23T01:34:02+00:00 app[web.1]:   Rendered searches/new.html.haml within layouts/application (707.1ms)
  2012-11-23T01:34:03+00:00 app[web.1]: Completed 500 Internal Server Error in 1694ms
  2012-11-23T01:34:03+00:00 app[web.1]: 
  2012-11-23T01:34:03+00:00 app[web.1]: ActionView::Template::Error (File to import not found or unreadable: bootstrap.
  2012-11-23T01:34:03+00:00 app[web.1]: Load path: /app
  2012-11-23T01:34:03+00:00 app[web.1]:     4:    %title 
  2012-11-23T01:34:03+00:00 app[web.1]:     5:        Seopositions
  2012-11-23T01:34:03+00:00 app[web.1]:     6:    = stylesheet_link_tag "application", :media =&gt; "all"
  2012-11-23T01:34:03+00:00 app[web.1]:   (in /app/app/assets/stylesheets/application.css.scss)):
  2012-11-23T01:34:03+00:00 app[web.1]: 
  2012-11-23T01:34:03+00:00 app[web.1]:   app/assets/stylesheets/application.css.scss:16
  2012-11-23T01:34:03+00:00 app[web.1]:   app/views/layouts/application.html.haml:6:in `_app_views_layouts_application_html_haml__2436706826874996932_32759700'
  2012-11-23T01:34:03+00:00 app[web.1]: cache: [GET /] miss
  2012-11-23T01:34:03+00:00 app[web.1]:     8:    = csrf_meta_tags
  2012-11-23T01:34:03+00:00 app[web.1]:     3: %head
  2012-11-23T01:34:03+00:00 app[web.1]:     7:    = javascript_include_tag "application"
  2012-11-23T01:34:03+00:00 app[web.1]:     9: %body
  2012-11-23T01:34:03+00:00 app[web.1]: 
  2012-11-23T01:34:03+00:00 heroku[router]: at=info method=GET path=/ host=seopositions-2.herokuapp.com fwd= dyno=web.1 queue=0 wait=2ms connect=5ms service=1939ms status=500 bytes=643
  2012-11-23T01:34:04+00:00 app[web.1]: cache: [GET /favicon.ico] miss
  2012-11-23T01:34:04+00:00 heroku[router]: at=info method=GET path=/favicon.ico host=seopositions-2.herokuapp.com fwd= dyno=web.1 queue=0 wait=0ms connect=3ms service=9ms status=200 bytes=0
  </code></pre>