I received error:
root@desktop:/home/michal# chef-solo 
Starting Chef Client, version 11.6.2
[2013-10-30T08:23:24+01:00] WARN: found a directory postfix in the cookbook path, but it contains no cookbook files. skipping.
Compiling Cookbooks...
Converging 6 resources
Recipe: base::default
  * cookbook_file[/home/michal/.screenrc] action create (up to date)
Recipe: postgresql::default
  * package[postgresql] action install (up to date)
  * execute[Create DB user] action run
================================================================================
Error executing action `run` on resource 'execute[Create DB user]'
================================================================================


Mixlib::ShellOut::ShellCommandFailed
------------------------------------
Expected process to exit with [0], but received '1'
---- Begin output of sudo postgres createuser michal ----
STDOUT: 
STDERR: sudo: postgres: command not found
---- End output of sudo postgres createuser michal ----
Ran sudo postgres createuser michal returned 1