"bin/rails: No such file or directory" w/ Ruby 2 & Rails 4 on Heroku

Question

While following the Rails 4 Beta version of Michael Hartl's Ruby on Rails Tutorial, my app fails to start on Heroku, but runs fine locally with bundle exec rails server. Checking heroku logs -t reveals the following error:

$ heroku[web.1]: State changed from crashed to starting
$ heroku[web.1]: Starting process with command `bin/rails server 
-p 33847 -e $RAILS_ENV`
$ app[web.1]: bash: bin/rails: No such file or directory
$ heroku[web.1]: Process exited with status 127
$ heroku[web.1]: State changed from starting to crashed
$ heroku[web.1]: Error R99 (Platform error) -> Failed to launch the 
dyno within 10 seconds
$ heroku[web.1]: Stopping process with SIGKILL

If I heroku run bash and check the bin directory, I can see that there is not a rails executable:

~$ ls bin
erb  gem  irb  node rdoc  ri  ruby  testrb

What have I done wrong? I followed the tutorial exactly.

Answer 1

I had this problem also since I upgraded to rails 4.0.0

Run this command

rake rails:update:bin

You can go here for more info https://devcenter.heroku.com/articles/rails4