diff --git a/lib/shoryuken/cli.rb b/lib/shoryuken/cli.rb
index 7a53d1a1..fb48f698 100644
--- a/lib/shoryuken/cli.rb
+++ b/lib/shoryuken/cli.rb
@@ -43,7 +43,7 @@ def run(args)
 
       @launcher = Shoryuken::Launcher.new
 
-      if callback = Shoryuken.start_callback
+      if (callback = Shoryuken.start_callback)
         logger.info { 'Calling Shoryuken.on_start block' }
         callback.call
       end
@@ -103,11 +103,9 @@ def daemonize(options)
     end
 
     def write_pid(options)
-      if (path = options[:pidfile])
-        File.open(path, 'w') do |f|
-          f.puts Process.pid
-        end
-      end
+      return unless (path = options[:pidfile])
+
+      File.open(path, 'w') { |f| f.puts(Process.pid) }
     end
 
     def parse_cli_args(argv)
diff --git a/lib/shoryuken/launcher.rb b/lib/shoryuken/launcher.rb
index 6027f1c0..8be1b021 100644
--- a/lib/shoryuken/launcher.rb
+++ b/lib/shoryuken/launcher.rb
@@ -7,23 +7,18 @@ def initialize
 
       raise(ArgumentError, "Concurrency value #{count} is invalid, it needs to be a positive number") unless count > 0
 
-      @managers = Array.new(count) do
-        Shoryuken::Manager.new(1,
-                               Shoryuken::Fetcher.new,
-                               Shoryuken.options[:polling_strategy].new(Shoryuken.queues))
-      end
+      @manager = Shoryuken::Manager.new(count,
+                                        Shoryuken::Fetcher.new,
+                                        Shoryuken.options[:polling_strategy].new(Shoryuken.queues))
     end
 
     def stop(options = {})
-      @managers.map do |manager|
-        Thread.new { manager.stop(shutdown: !!options[:shutdown], timeout: Shoryuken.options[:timeout]) }
-      end.each(&:join)
+      @manager.stop(shutdown: !options[:shutdown].nil?,
+                    timeout: Shoryuken.options[:timeout])
     end
 
     def run
-      @managers.map do |manager|
-        Thread.new { manager.start }
-      end.each(&:join)
+      @manager.start
     end
   end
 end