Sensu Client for OpenBSD OS - openbsd

Question

we are migrating or monitoring from nagios to sensu and part of this is moving our openbsd servers to sensu. i know there is no native client for this but i have been wondering if anyone has tried and succeeded at this.
couldn't find anything much helpful so far so any help will appreciated.
all i found so far was this link
but i couldn't figure out how he did this.
i also tried creating a new box and installing the sensu client via gem install sensu, the install finished with no errors but the client did not run and i got this:
-bash-4.3# sensu-client18
/usr/local/lib/ruby/gems/1.8/gems/ffi-1.9.10/lib/ffi_c.so: Cannot load specified object - /usr/local/lib/ruby/gems/1.8/gems/ffi-1.9.10/lib/ffi_c.so (LoadError)
from /usr/local/lib/ruby/site_ruby/1.8/rubygems/cust
from /usr/local/lib/ruby/site_ruby/1.8/rubyg
from /usr/local/lib/ruby/gems/1.8/gems/sensu
from /usr/local/lib/ruby/site_ruby/1.8/rubyg
from /usr/local/lib/ruby/site_ruby/1.8/rubyg
from /usr/local/lib/ruby/gems/1.8/gems/sensu
from /usr/local/lib/ruby/site_ruby/1.8/rubyg
from /usr/local/lib/ruby/site_ruby/1.8/rubyg
from /usr/local/lib/ruby/gems/1.8/gems/sensu
from /usr/local/lib/ruby/site_ruby/1.8/rubyg
from /usr/local/lib/ruby/site_ruby/1.8/rubyg
from /usr/local/lib/ruby/gems/1.8/gems/sensu
from /usr/local/bin/sensu-client18:23:in `lo
from /usr/local/bin/sensu-client18:23
install process:
*** LOCAL GEMS ***
-bash-4.3# gem18 install sensu
Fetching: multi_json-1.11.2.gem (100%)
Fetching: uuidtools-2.1.5.gem (100%)
Fetching: eventmachine-1.0.8.gem (100%)
Building native extensions. This could take a while>Fetching: sensu-logger-1.1.0.gem (100%)
Fetching: sensu-settings-3.3.0.gem (100%)
Fetching: sensu-extension-1.3.0.gem (100%)
Fetching: sensu-extensions-1.4.0.gem (100%)
Fetching: amq-protocol-1.9.2.gem (100%)
Fetching: amqp-1.5.0.gem (100%)
Fetching: em-redis-unified-1.0.1.gem (100%)
Fetching: sensu-transport-3.3.0.gem (100%)
Fetching: em-worker-0.0.2.gem (100%)
Fetching: ffi-1.9.10.gem (100%)
Building native extensions. This could take a while>Fetching: childprocess-0.5.8.gem (100%)
Fetching: sensu-spawn-1.6.0.gem (100%)
Fetching: rack-1.6.4.gem (100%)
Fetching: tilt-2.0.2.gem (100%)
Fetching: rack-protection-1.5.3.gem (100%)
Fetching: sinatra-1.4.6.gem (100%)
Fetching: async_sinatra-1.2.0.gem (100%)
Fetching: daemons-1.2.3.gem (100%)
Fetching: thin-1.6.3.gem (100%)
Building native extensions. This could take a while>Fetching: sensu-
0.22.0.gem (100%)
Successfully installed multi_json-1.11.2
Successfully installed uuidtools-2.1.5
Successfully installed eventmachine-1.0.8
Successfully installed sensu-logger-1.1.0
Successfully installed sensu-settings-3.3.0
Successfully installed sensu-extension-1.3.0
Successfully installed sensu-extensions-1.4.0
Successfully installed amq-protocol-1.9.2
Successfully installed amqp-1.5.0
Successfully installed em-redis-unified-1.0.1
Successfully installed sensu-transport-3.3.0
Successfully installed em-worker-0.0.2
Successfully installed ffi-1.9.10
Successfully installed childprocess-0.5.8
Successfully installed sensu-spawn-1.6.0
Successfully installed rack-1.6.4
Successfully installed tilt-2.0.2
Successfully installed rack-protection-1.5.3
Successfully installed sinatra-1.4.6
Successfully installed async_sinatra-1.2.0
Successfully installed daemons-1.2.3
Successfully installed thin-1.6.3
Successfully installed sensu-0.22.0
23 gems installed
any thoughts guys?
EDIT: i should mention, i am very new to ruby so i might be missing something very dumb here

Answer 1

I tried in and adJ OpenBSD 6.0 and it seems to work fine.
$ doas pkg_add ruby
$ doas gem install sensu
$ sensu-client -V
0.26.5
I even could start the server and the client using redis as transport.