Connection refused on Nickserver at port 4000 - local provider

Nickserver logs when trying to use local provider with pixelated-user-agent -

I, [2017-05-10T16:43:09.495298 #4356]  INFO -- : GET /?address=test1@pixelated-project.local
D, [2017-05-10T16:43:09.495821 #4356] DEBUG -- :   {"address"=>["test1@pixelated-project.local"]}
E, [2017-05-10T16:43:09.499123 #4356] ERROR -- : Actor crashed!
HTTP::ConnectionError: failed to connect: Connection refused - connect(2) for "localhost" port 4000
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/http-2.0.3/lib/http/timeout/null.rb:20:in `initialize'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/http-2.0.3/lib/http/timeout/null.rb:20:in `open'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/http-2.0.3/lib/http/timeout/null.rb:20:in `connect'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/http-2.0.3/lib/http/connection.rb:41:in `initialize'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/http-2.0.3/lib/http/client.rb:60:in `new'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/http-2.0.3/lib/http/client.rb:60:in `perform'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/http-2.0.3/lib/http/client.rb:41:in `request'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/http-2.0.3/lib/http/chainable.rb:19:in `get'
        /srv/leap/nickserver/lib/nickserver/adapters/http.rb:18:in `get_with_auth'
        /srv/leap/nickserver/lib/nickserver/adapters/http.rb:10:in `get'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/celluloid-0.17.3/lib/celluloid/calls.rb:28:in `public_send'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/celluloid-0.17.3/lib/celluloid/calls.rb:28:in `dispatch'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/celluloid-0.17.3/lib/celluloid/call/sync.rb:16:in `dispatch'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/celluloid-0.17.3/lib/celluloid/cell.rb:50:in `block in dispatch'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/celluloid-0.17.3/lib/celluloid/cell.rb:76:in `block in task'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/celluloid-0.17.3/lib/celluloid/actor.rb:339:in `block in task'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/celluloid-0.17.3/lib/celluloid/task.rb:44:in `block in initialize'
        /srv/leap/nickserver/vendor/bundle/ruby/2.1.0/gems/celluloid-0.17.3/lib/celluloid/task/fibered.rb:14:in `block in create'
I, [2017-05-10T16:43:11.836975 #4356]  INFO -- :  -> 502

And the URL that it tries to query CouchDB for the key -

http://nickserver:passwd@localhost:4000/identities/_design/Identity/_view/pgp_key_by_email