[erlang-questions] Problems with cowboy:start_clear() - undefined function

[Drasko DRASKOVIC]

Hi all,
I am trying to run https://github.com/drasko/erlang-starter-kit and I
am getting:

Exec: /home/drasko/erlang/esk/_rel/esk_release/erts-9.3.3.3/bin/erlexec
-boot /home/drasko/erlang/esk/_rel/esk_release/releases/1/esk_release
-mode embedded -boot_var ERTS_LIB_DIR
/home/drasko/erlang/esk/_rel/esk_release/lib -config
/home/drasko/erlang/esk/_rel/esk_release/releases/1/sys.config
-args_file /home/drasko/erlang/esk/_rel/esk_release/releases/1/vm.args
-pa -- console
Root: /home/drasko/erlang/esk/_rel/esk_release
/home/drasko/erlang/esk/_rel/esk_release
heart_beat_kill_pid = 3160
Erlang/OTP 20 [erts-9.3.3.3] [source] [64-bit] [smp:8:8] [ds:8:8:10]
[async-threads:10] [kernel-poll:false]

17:23:46.517 [info] Application lager started on node 'esk@REDACTED'
17:23:46.517 [info] Application asn1 started on node 'esk@REDACTED'
17:23:46.518 [info] Application public_key started on node 'esk@REDACTED'
17:23:46.519 [info] Application ssl started on node 'esk@REDACTED'
17:23:46.519 [info] Application unicode_util_compat started on node
'esk@REDACTED'
17:23:46.519 [info] Application idna started on node 'esk@REDACTED'
17:23:46.519 [info] Application mimerl started on node 'esk@REDACTED'
17:23:46.520 [info] Application certifi started on node 'esk@REDACTED'
17:23:46.520 [info] Application ssl_verify_fun started on node 'esk@REDACTED'
17:23:46.520 [info] Application metrics started on node 'esk@REDACTED'
17:23:46.520 [info] Application hackney started on node 'esk@REDACTED'
17:23:46.521 [info] Application couchbeam started on node 'esk@REDACTED'
17:23:46.522 [error] CRASH REPORT Process <0.608.0> with 0 neighbours
exited with reason: call to undefined function
cowboy:start_clear(esk_cowboy, [{ip,{0,0,0,0}},{port,8089}], #{env =>
#{dispatch => [{'_',[],[{[<<"status">>],[],esk_status,[]},{[<<"user">>],[],esk_user,...},...]}]}})
in application_master:init/4 line 134
17:23:46.522 [info] Application esk exited with reason: call to
undefined function cowboy:start_clear(esk_cowboy,
[{ip,{0,0,0,0}},{port,8089}], #{env => #{dispatch =>
[{'_',[],[{[<<"status">>],[],esk_status,[]},{[<<"user">>],[],esk_user,...},...]}]}})
{"Kernel pid terminated",application_controller,"{application_start_failure,esk,{bad_return,{{esk_app,start,[normal,[]]},{'EXIT',{undef,[{cowboy,start_clear,[esk_cowboy,[{ip,{0,0,0,0}},{port,8089}],#{env
=> #{dispatch =>
[{'_',[],[{[<<\"status\">>],[],esk_status,[]},{[<<\"user\">>],[],esk_user,[]},{[<<\"login\">>],[],esk_login,[]}]}]}}],[]},{esk_app,start,2,[{file,\"src/esk_app.erl\"},{line,32}]},{application_master,start_it_old,4,[{file,\"application_master.erl\"},{line,273}]}]}}}}}"}
Kernel pid terminated (application_controller)
({application_start_failure,esk,{bad_return,{{esk_app,start,[normal,[]]},{'EXIT',{undef,[{cowboy,start_clear,[esk_cowboy,[{ip,{0,0,0,0}},{port,8089}],#{e
heart: Sun Aug 26 17:23:48 2018: Erlang is crashing .. (waiting for
crash dump file)
heart: Sun Aug 26 17:23:48 2018: Would reboot. Terminating.
make: *** [erlang.mk:6782: run] Error 1

Any idea why this is happening?

I am running Debian Buster with Erlang/OTP 20.

BR,
Drasko