error from unicorn

gistfile1.txt

E, [2013-11-24T08:23:48.282063 #20438] ERROR -- : reaped #<Process::Status: pid 29427 exit 1> worker=1
I, [2013-11-24T08:23:48.282426 #20438]  INFO -- : worker=1 spawning...
I, [2013-11-24T08:23:48.283720 #29440]  INFO -- : worker=1 spawned pid=29440
I, [2013-11-24T08:23:48.301879 #29440]  INFO -- : Refreshing Gem list
E, [2013-11-24T08:23:48.343457 #29430] ERROR -- : couldn't find HOME environment -- expanding `~' (ArgumentError)
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/guard-1.8.3/lib/guard.rb:23:in `expand_path'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/guard-1.8.3/lib/guard.rb:23:in `<module:Guard>'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/guard-1.8.3/lib/guard.rb:8:in `<top (required)>'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:72:in `require'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:72:in `block (2 levels) in require'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:70:in `each'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:70:in `block in require'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:59:in `each'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler/runtime.rb:59:in `require'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/bundler-1.3.5/lib/bundler.rb:132:in `require'
/home/rails/config/application.rb:7:in `<top (required)>'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
/home/rails/config/environment.rb:2:in `<top (required)>'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
config.ru:4:in `block in <main>'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/builder.rb:55:in `instance_eval'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/rack-1.5.2/lib/rack/builder.rb:55:in `initialize'
config.ru:1:in `new'
config.ru:1:in `<main>'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/unicorn-4.6.3/lib/unicorn.rb:48:in `eval'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/unicorn-4.6.3/lib/unicorn.rb:48:in `block in builder'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/unicorn-4.6.3/lib/unicorn/http_server.rb:722:in `call'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/unicorn-4.6.3/lib/unicorn/http_server.rb:722:in `build_app!'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/unicorn-4.6.3/lib/unicorn/http_server.rb:595:in `init_worker_process'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/unicorn-4.6.3/lib/unicorn/http_server.rb:615:in `worker_loop'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/unicorn-4.6.3/lib/unicorn/http_server.rb:500:in `spawn_missing_workers'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/unicorn-4.6.3/lib/unicorn/http_server.rb:511:in `maintain_worker_count'
/usr/local/rvm/rubies/ruby-1.9.3-p429/lib/ruby/gems/1.9.1/gems/unicorn-4.6.3/lib/unicorn/http_server.rb:277:in `join'
/usr/bin/unicorn:121:in `<main>'