diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 92f3cd73..8b03267e 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -20,14 +20,20 @@ test_ruby21:
   script:
     ./spec.sh ruby 2.1
 test_ruby22:
+  only:
+    - master
   stage: test
   script:
     ./spec.sh ruby 2.2
 test_ruby23:
+  only:
+    - master
   stage: test
   script:
     ./spec.sh ruby 2.3
 test_ruby24:
+  only:
+    - master
   stage: test
   script:
     ./spec.sh ruby 2.4
diff --git a/Gemfile b/Gemfile
index 4ca510e7..b9f7ab59 100644
--- a/Gemfile
+++ b/Gemfile
@@ -7,7 +7,7 @@ gemspec
 
 gem "hanna-nouveau", require: false
 gem "rake", "~> 12.3"
-gem "rubocop", require: false
+gem "rubocop", "~> 0.52.1", require: false
 gem "simplecov", require: false
 
 platform :mri do
diff --git a/README.md b/README.md
index 64b27b83..620dddd7 100644
--- a/README.md
+++ b/README.md
@@ -90,6 +90,10 @@ It means that it loads the bare minimum to perform requests, and the user has to
 
 It also means that it ships with the minimum amount of dependencies.
 
+## Easy to test
+
+The test suite runs against [httpbin proxied over nghttp2](https://nghttp2.org/httpbin/), so there is no mocking/stubbing going on. The test suite uses [minitest](https://github.com/seattlerb/minitest), but its matchers usage is limit to assert (assert is all you need).
+
 ## Supported Rubies
 
 All Rubies greater or equal to 2.1, and always latest JRuby.
diff --git a/lib/httpx/channel.rb b/lib/httpx/channel.rb
index 8bee7e62..d6ef3856 100644
--- a/lib/httpx/channel.rb
+++ b/lib/httpx/channel.rb
@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 
+require "resolv"
 require "forwardable"
 require "httpx/io"
 require "httpx/buffer"
@@ -68,13 +69,13 @@ module HTTPX
     end
 
     def match?(uri)
-      ip = begin
-             TCPSocket.getaddress(uri.host)
-           rescue StandardError
-             uri.host
-           end
+      ips = begin
+        Resolv.getaddresses(uri.host)
+      rescue StandardError
+        [uri.host]
+      end
 
-      ip == @io.ip &&
+      ips.include?(@io.ip) &&
         uri.port == @io.port &&
         uri.scheme == @io.scheme
     end
@@ -98,18 +99,9 @@ module HTTPX
       @io.to_io
     end
 
-    def close(hard = false)
-      pr = @parser
+    def close
+      @parser.close
       transition(:closing)
-      if hard || (pr && pr.empty?)
-        pr.close
-        @parser = nil
-      else
-        transition(:idle)
-        @parser = pr
-        parser.reenqueue!
-        return
-      end
     end
 
     def reset
@@ -154,7 +146,10 @@ module HTTPX
     def dread(wsize = @window_size)
       loop do
         siz = @io.read(wsize, @read_buffer)
-        throw(:close, self) unless siz
+        unless siz
+          emit(:close)
+          return
+        end
         return if siz.zero?
         log { "READ: #{siz} bytes..." }
         parser << @read_buffer.to_s
@@ -165,7 +160,10 @@ module HTTPX
       loop do
         return if @write_buffer.empty?
         siz = @io.write(@write_buffer)
-        throw(:close, self) unless siz
+        unless siz
+          emit(:close)
+          return
+        end
         log { "WRITE: #{siz} bytes..." }
         return if siz.zero?
       end
@@ -190,11 +188,8 @@ module HTTPX
       parser.on(:promise) do |*args|
         emit(:promise, *args)
       end
-      # parser.inherit_callbacks(self)
-      parser.on(:complete) { throw(:close, self) }
       parser.on(:close) do
-        transition(:closed)
-        emit(:close)
+        transition(:closing)
       end
       parser
     end
diff --git a/lib/httpx/channel/http1.rb b/lib/httpx/channel/http1.rb
index d1ee5742..ee3c9591 100644
--- a/lib/httpx/channel/http1.rb
+++ b/lib/httpx/channel/http1.rb
@@ -151,7 +151,7 @@ module HTTPX
         # 1 keep alive request.
         @max_concurrent_requests = 1
       end
-      emit(:complete)
+      emit(:close)
     end
 
     private
diff --git a/lib/httpx/channel/http2.rb b/lib/httpx/channel/http2.rb
index 96e97b1d..680444da 100644
--- a/lib/httpx/channel/http2.rb
+++ b/lib/httpx/channel/http2.rb
@@ -170,7 +170,7 @@ module HTTPX
 
     def on_close(*)
       return unless @connection.state == :closed && @connection.active_stream_count.zero?
-      emit(:complete)
+      emit(:close)
     end
 
     def on_frame_sent(frame)
diff --git a/lib/httpx/connection.rb b/lib/httpx/connection.rb
index a58eadfd..54ead50d 100644
--- a/lib/httpx/connection.rb
+++ b/lib/httpx/connection.rb
@@ -19,19 +19,15 @@ module HTTPX
     def next_tick(timeout: @timeout.timeout)
       @selector.select(timeout) do |monitor|
         if (channel = monitor.value)
-          consume(channel)
+          channel.call
         end
         monitor.interests = channel.interests
       end
     end
 
-    def close(channel = nil)
-      if channel
-        channel.close
-      else
-        @channels.each(&:close)
-        next_tick until @selector.empty?
-      end
+    def close
+      @channels.each(&:close)
+      next_tick until @channels.empty?
     end
 
     def reset
@@ -65,10 +61,5 @@ module HTTPX
       end
       @channels << channel
     end
-
-    def consume(channel)
-      ch = catch(:close) { channel.call }
-      close(ch) if ch
-    end
   end
 end
diff --git a/lib/httpx/io.rb b/lib/httpx/io.rb
index 7c63c125..24243495 100644
--- a/lib/httpx/io.rb
+++ b/lib/httpx/io.rb
@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 
+require "resolv"
 require "socket"
 require "openssl"
 require "ipaddr"
@@ -19,7 +20,7 @@ module HTTPX
       if @options.io
         @io = case @options.io
               when Hash
-                @ip = TCPSocket.getaddress(hostname)
+                @ip = Resolv.getaddress(@hostname)
                 @options.io[@ip] || @options.io["#{@ip}:#{@port}"]
               else
                 @ip = hostname
@@ -30,7 +31,7 @@ module HTTPX
           @state = :connected
         end
       else
-        @ip = TCPSocket.getaddress(hostname)
+        @ip = Resolv.getaddress(@hostname)
       end
       @io ||= build_socket
     end
diff --git a/lib/httpx/plugins/proxy/http.rb b/lib/httpx/plugins/proxy/http.rb
index b5a1f97a..3bdcd0c3 100644
--- a/lib/httpx/plugins/proxy/http.rb
+++ b/lib/httpx/plugins/proxy/http.rb
@@ -34,7 +34,7 @@ module HTTPX
               return if @io.closed?
               @parser = ConnectProxyParser.new(@write_buffer, @options.merge(max_concurrent_requests: 1))
               @parser.once(:response, &method(:on_connect))
-              @parser.on(:complete) { throw(:close, self) }
+              @parser.on(:close) { transition(:closing) }
               proxy_connect
               return if @state == :open
             when :open
@@ -45,7 +45,7 @@ module HTTPX
               when :idle
                 @parser = ProxyParser.new(@write_buffer, @options)
                 @parser.inherit_callbacks(self)
-                @parser.on(:complete) { throw(:close, self) }
+                @parser.on(:close) { transition(:closing) }
               end
             end
             super
diff --git a/lib/httpx/selector.rb b/lib/httpx/selector.rb
index 79c87b31..8eeb3e69 100644
--- a/lib/httpx/selector.rb
+++ b/lib/httpx/selector.rb
@@ -48,10 +48,6 @@ class HTTPX::Selector
     @closed = false
   end
 
-  def empty?
-    @readers.empty? && @writers.empty?
-  end
-
   # deregisters +io+ from selectables.
   def deregister(io)
     @lock.synchronize do