Error with ruby when pushing app

[berenyiaustin]

I'm attempting to set this up. I'm following the documentation on Heroku but I keep getting this error no matter what I do. When I follow the same process with their example node-js-getting-started app everything works fine. No errors. I copy the same process but use the SpotifyTokenSwap repo instead. Ruby ruby 2.1.5p273 is installed. I just verified this.

Can anyone tell what's going on?

$ git push heroku master

Counting objects: 58, done.
Delta compression using up to 8 threads.
Compressing objects: 100% (55/55), done.
Writing objects: 100% (58/58), 9.20 KiB | 3.07 MiB/s, done.
Total 58 (delta 24), reused 0 (delta 0)
remote: Compressing source files... done.
remote: Building source:
remote: 
remote: -----> Ruby app detected
remote: -----> Compiling Ruby/Rack
remote:        Command: 'set -o pipefail; curl -L --fail --retry 5 --retry-delay 1 --connect-timeout 3 --max-time 30 https://s3-external-1.amazonaws.com/heroku-buildpack-ruby/heroku-16/ruby-2.1.5.tgz -s -o - | tar zxf - ' failed on attempt 1 of 3.
remote:        Command: 'set -o pipefail; curl -L --fail --retry 5 --retry-delay 1 --connect-timeout 3 --max-time 30 https://s3-external-1.amazonaws.com/heroku-buildpack-ruby/heroku-16/ruby-2.1.5.tgz -s -o - | tar zxf - ' failed on attempt 2 of 3.
remote: 
remote:  !
remote:  !     An error occurred while installing ruby-2.1.5
remote:  !     
remote:  !     Heroku recommends you use the latest supported Ruby version listed here:
remote:  !     https://devcenter.heroku.com/articles/ruby-support#supported-runtimes
remote:  !     
remote:  !     For more information on syntax for declaring a Ruby version see:
remote:  !     https://devcenter.heroku.com/articles/ruby-versions
remote:  !     
remote:  !     
remote:  !     Debug InformationCommand: 'set -o pipefail; curl -L --fail --retry 5 --retry-delay 1 --connect-timeout 3 --max-time 30 https://s3-external-1.amazonaws.com/heroku-buildpack-ruby/heroku-16/ruby-2.1.5.tgz -s -o - | tar zxf - ' failed unexpectedly:
remote:  !     
remote:  !     gzip: stdin: unexpected end of file
remote:  !     tar: Child returned status 1
remote:  !     tar: Error is not recoverable: exiting now
remote:  !
remote:  !     Push rejected, failed to compile Ruby app.
remote: 
remote:  !     Push failed
remote: Verifying deploy...
remote: 
remote: !   Push rejected to guarded-tor-50875.
remote: 
To https://git.heroku.com/guarded-tor-50875.git
 ! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to 'https://git.heroku.com/guarded-tor-50875.git'

[ohadvano]

Copy Gemfile and Gemfile.lock from heroku "jruby-getting-started" repo to "SpotifyTokenSwap" (follow https://devcenter.heroku.com/articles/getting-started-with-jruby#deploy-the-app), then commit changes to the master branch, then try to push again.