diff --git a/.gitignore b/.gitignore
index 65cbda8..fe7f5d5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,6 +3,5 @@
 *.gem
 coverage/
 log/
-tmp/
 .ruby-version
 history.yml
diff --git a/.travis.yml b/.travis.yml
index f68ed76..efb2a95 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,8 @@
 language: ruby
 rvm:
-  - 2.3.0
-  - 2.2.4
-  - 2.1.8
-
-script: "rake test"
+  - 2.3.4
+  - 2.2.7
+  - 2.1.10
+  - jruby-19mode
+  - jruby-9.1.10.0
+script: rake test
diff --git a/README.md b/README.md
index 6ff4065..1aa914b 100644
--- a/README.md
+++ b/README.md
@@ -22,7 +22,7 @@ $ cd my-project
 # Install the bundle of project specific gems
 $ bundle
 # Start the example dashboard!
-$ smashing start
+$ puma
 ```
 
 [Check out our wiki](https://github.com/Smashing/smashing/wiki).
diff --git a/Rakefile b/Rakefile
index fc91969..da4603e 100644
--- a/Rakefile
+++ b/Rakefile
@@ -6,6 +6,7 @@ require 'rake/testtask'
 Rake::TestTask.new(:test) do |test|
   test.libs << 'lib' << 'test'
   test.pattern = 'test/**/*_test.rb'
+  test.warning = false
 end
 
-task :default => [:test]
+task default: [:test]
diff --git a/lib/dashing/app.rb b/lib/dashing/app.rb
index 5ee085f..d40cc0a 100644
--- a/lib/dashing/app.rb
+++ b/lib/dashing/app.rb
@@ -1,12 +1,12 @@
-require 'sinatra'
-require 'sprockets'
-require 'sinatra/content_for'
-require 'rufus/scheduler'
 require 'coffee-script'
-require 'sass'
 require 'json'
+require 'rufus/scheduler'
+require 'sass'
+require 'sinatra'
+require 'sinatra/content_for'
+require 'sinatra/streaming'
+require 'sprockets'
 require 'yaml'
-require 'thin'
 
 SCHEDULER = Rufus::Scheduler.new
 
@@ -34,13 +34,14 @@ def authenticated?(token)
 set :sprockets,     Sprockets::Environment.new(settings.root)
 set :assets_prefix, '/assets'
 set :digest_assets, false
-set :server, 'thin'
+set :server, 'puma'
 set :connections, []
 set :history_file, 'history.yml'
 set :public_folder, File.join(settings.root, 'public')
 set :views, File.join(settings.root, 'dashboards')
 set :default_dashboard, nil
 set :auth_token, nil
+set :template_languages, %i[html erb]
 
 if File.exists?(settings.history_file)
   set :history, YAML.load_file(settings.history_file)
@@ -57,7 +58,7 @@ def authenticated?(token)
 end
 
 not_found do
-  send_file File.join(settings.public_folder, '404.html'), :status => 404
+  send_file File.join(settings.public_folder, '404.html'), status: 404
 end
 
 at_exit do
@@ -72,21 +73,31 @@ def authenticated?(token)
   redirect "/" + dashboard
 end
 
-get '/events', :provides => 'text/event-stream' do
+
+get '/events', provides: 'text/event-stream' do
   protected!
   response.headers['X-Accel-Buffering'] = 'no' # Disable buffering for nginx
-  stream :keep_open do |out|
-    settings.connections << out
+  stream do |out|
     out << latest_events
-    out.callback { settings.connections.delete(out) }
+    settings.connections << connection = {out: out, mutex: Mutex.new, terminated: false}
+    terminated = false
+
+    loop do
+      connection[:mutex].synchronize do
+        terminated = true if connection[:terminated]
+      end
+      break if terminated
+    end
+
+    settings.connections.delete(connection)
   end
 end
 
 get '/:dashboard' do
   protected!
-  tilt_html_engines.each do |suffix, _|
-    file = File.join(settings.views, "#{params[:dashboard]}.#{suffix}")
-    return render(suffix.to_sym, params[:dashboard].to_sym) if File.exist? file
+  settings.template_languages.each do |language|
+    file = File.join(settings.views, "#{params[:dashboard]}.#{language}")
+    return render(language, params[:dashboard].to_sym) if File.exist?(file)
   end
 
   halt 404
@@ -119,21 +130,12 @@ def authenticated?(token)
 
 get '/views/:widget?.html' do
   protected!
-  tilt_html_engines.each do |suffix, engines|
-    file = File.join(settings.root, "widgets", params[:widget], "#{params[:widget]}.#{suffix}")
-    return engines.first.new(file).render if File.exist? file
-  end
-  "Drats! Unable to find a widget file named: #{params[:widget]} to render."
-end
-
-Thin::Server.class_eval do
-  def stop_with_connection_closing
-    Sinatra::Application.settings.connections.dup.each(&:close)
-    stop_without_connection_closing
+  settings.template_languages.each do |language|
+    file = File.join(settings.root, "widgets", params[:widget], "#{params[:widget]}.#{language}")
+    return Tilt[language].new(file).render if File.exist?(file)
   end
 
-  alias_method :stop_without_connection_closing, :stop
-  alias_method :stop, :stop_with_connection_closing
+  "Drats! Unable to find a widget file named: #{params[:widget]} to render."
 end
 
 def send_event(id, body, target=nil)
@@ -141,7 +143,18 @@ def send_event(id, body, target=nil)
   body[:updatedAt] ||= Time.now.to_i
   event = format_event(body.to_json, target)
   Sinatra::Application.settings.history[id] = event unless target == 'dashboards'
-  Sinatra::Application.settings.connections.each { |out| out << event }
+  Sinatra::Application.settings.connections.each do |connection|
+    connection[:mutex].synchronize do
+      begin
+        connection[:out] << event unless connection[:out].closed?
+      rescue Puma::ConnectionError
+        connection[:terminated] = true
+      rescue Exception => e
+        connection[:terminated] = true
+        puts e
+      end
+    end
+  end
 end
 
 def format_event(body, name=nil)
@@ -162,13 +175,6 @@ def first_dashboard
   files.sort.first
 end
 
-def tilt_html_engines
-  Tilt.mappings.select do |_, engines|
-    default_mime_type = engines.first.default_mime_type
-    default_mime_type.nil? || default_mime_type == 'text/html'
-  end
-end
-
 def require_glob(relative_glob)
   Dir[File.join(settings.root, relative_glob)].each do |file|
     require file
diff --git a/lib/dashing/cli.rb b/lib/dashing/cli.rb
index 4b93f89..b141187 100644
--- a/lib/dashing/cli.rb
+++ b/lib/dashing/cli.rb
@@ -54,22 +54,6 @@ def install(gist_id, *args)
       say set_color("Could not find gist at #{public_url}"), :red
     end
 
-    desc "start", "Starts the server in style!"
-    method_option :job_path, :desc => "Specify the directory where jobs are stored"
-    def start(*args)
-      port_option = args.include?('-p') ? '' : ' -p 3030'
-      args = args.join(' ')
-      command = "bundle exec thin -R config.ru start#{port_option} #{args}"
-      command.prepend "export JOB_PATH=#{options[:job_path]}; " if options[:job_path]
-      run_command(command)
-    end
-
-    desc "stop", "Stops the thin server"
-    def stop
-      command = "bundle exec thin stop"
-      run_command(command)
-    end
-
     desc "job JOB_NAME AUTH_TOKEN(optional)", "Runs the specified job. Make sure to supply your auth token if you have one set."
     def job(name, auth_token = "")
       Dir[File.join(Dir.pwd, 'lib/**/*.rb')].each {|file| require_file(file) }
@@ -94,10 +78,10 @@ def install_widget_from_gist(gist, skip_overwrite)
         if file =~ /\.(html|coffee|scss)\z/
           widget_name = File.basename(file, '.*')
           new_path = File.join(Dir.pwd, 'widgets', widget_name, file)
-          create_file(new_path, details['content'], :skip => skip_overwrite)
+          create_file(new_path, details['content'], skip: skip_overwrite)
         elsif file.end_with?('.rb')
           new_path = File.join(Dir.pwd, 'jobs', file)
-          create_file(new_path, details['content'], :skip => skip_overwrite)
+          create_file(new_path, details['content'], skip: skip_overwrite)
         end
       end
     end
diff --git a/smashing.gemspec b/smashing.gemspec
index c8f1cb2..5043886 100644
--- a/smashing.gemspec
+++ b/smashing.gemspec
@@ -15,21 +15,21 @@ Gem::Specification.new do |s|
 
   s.files = Dir['README.md', 'javascripts/**/*', 'templates/**/*','templates/**/.[a-z]*', 'lib/**/*']
 
-  s.add_dependency('sass', '~> 3.2.12')
-  s.add_dependency('coffee-script', '~> 2.2.0')
-  s.add_dependency('execjs', '~> 2.0.2')
-  s.add_dependency('sinatra', '~> 1.4.4')
-  s.add_dependency('sinatra-contrib', '~> 1.4.2')
-  s.add_dependency('thin', '~> 1.6.1')
-  s.add_dependency('rufus-scheduler', '~> 2.0.24')
-  s.add_dependency('thor', '~> 0.19')
-  s.add_dependency('sprockets', '~> 2.10.1')
-  s.add_dependency('rack', '~> 1.5.4')
+  s.add_dependency('sass', '~> 3.4.24')
+  s.add_dependency('coffee-script', '~> 2.4.1')
+  s.add_dependency('execjs', '~> 2.7.0')
+  s.add_dependency('sinatra', '~> 2.0.0')
+  s.add_dependency('sinatra-contrib', '~> 2.0.0')
+  s.add_dependency('puma', '~> 3.8.2')
+  s.add_dependency('rufus-scheduler', '~> 3.4.2')
+  s.add_dependency('thor', '~> 0.19.4')
+  s.add_dependency('sprockets', '~> 3.7.1')
 
-  s.add_development_dependency('rake', '~> 10.1.0')
-  s.add_development_dependency('haml', '~> 4.0.4')
-  s.add_development_dependency('minitest', '~> 5.2.0')
-  s.add_development_dependency('mocha', '~> 0.14.0')
+  s.add_development_dependency('rake', '~> 12.0.0')
+  s.add_development_dependency('haml', '~> 5.0.1')
+  s.add_development_dependency('rack-test', '~> 0.6.3')
+  s.add_development_dependency('minitest', '~> 5.10.2')
+  s.add_development_dependency('mocha', '~> 1.2.1')
   s.add_development_dependency('fakeweb', '~> 1.3.0')
-  s.add_development_dependency('simplecov', '~> 0.8.2')
+  s.add_development_dependency('simplecov', '~> 0.14.1')
 end
diff --git a/templates/job/%name%.rb b/templates/job/%name%.rb
index 76f221a..c5c00c7 100644
--- a/templates/job/%name%.rb
+++ b/templates/job/%name%.rb
@@ -1,4 +1,4 @@
 # :first_in sets how long it takes before the job is first run. In this case, it is run immediately
-SCHEDULER.every '1m', :first_in => 0 do |job|
+SCHEDULER.every '1m', first_in: 0 do |job|
   send_event('widget_id', { })
-end
\ No newline at end of file
+end
diff --git a/templates/project/config.ru b/templates/project/config.ru
index 624244e..eecd5e0 100644
--- a/templates/project/config.ru
+++ b/templates/project/config.ru
@@ -3,6 +3,10 @@ require 'dashing'
 configure do
   set :auth_token, 'YOUR_AUTH_TOKEN'
 
+  # See http://www.sinatrarb.com/intro.html > Available Template Languages on
+  # how to add additional template languages.
+  set :template_languages, %i[html erb]
+
   helpers do
     def protected!
       # Put any authentication code you want in here.
diff --git a/templates/project/config/puma.rb b/templates/project/config/puma.rb
new file mode 100644
index 0000000..26140fa
--- /dev/null
+++ b/templates/project/config/puma.rb
@@ -0,0 +1,42 @@
+# For a complete list of puma configuration parameters, please see
+# https://github.com/puma/puma
+
+# Puma can serve each request in a thread from an internal thread pool.
+# The `threads` method setting takes two numbers a minimum and maximum.
+# Any libraries that use thread pools should be configured to match
+# the maximum value specified for Puma. Default is set to 5 threads for minimum
+# and maximum.
+#
+threads_count = ENV.fetch("PUMA_MAX_THREADS") { 5 }.to_i
+threads threads_count, threads_count
+
+# Specifies the `port` that Puma will listen on to receive requests, default is 2020.
+#
+port        ENV.fetch("DASHING_PORT") { 3030 }
+
+# Specifies the `environment` that Puma will run in.
+#
+environment ENV.fetch("RACK_ENV") { "production" }
+
+# Daemonize the server into the background. Highly suggest that
+# this be combined with "pidfile" and "stdout_redirect".
+#
+# The default is "false".
+#
+daemonize ENV.fetch("DAEMONIZE") { false }
+
+# Store the pid of the server in the file at "path".
+#
+pidfile './tmp/pids/puma.pid'
+
+# Use "path" as the file to store the server info state. This is
+# used by "pumactl" to query and control the server.
+#
+state_path './tmp/pids/puma.state'
+
+# Redirect STDOUT and STDERR to files specified. The 3rd parameter
+# ("append") specifies whether the output is appended, the default is
+# "false".
+#
+# stdout_redirect '/u/apps/lolcat/log/stdout', '/u/apps/lolcat/log/stderr'
+# stdout_redirect '/u/apps/lolcat/log/stdout', '/u/apps/lolcat/log/stderr', true
\ No newline at end of file
diff --git a/templates/project/jobs/twitter.rb b/templates/project/jobs/twitter.rb
index 7b2bd6f..0cac98e 100644
--- a/templates/project/jobs/twitter.rb
+++ b/templates/project/jobs/twitter.rb
@@ -12,7 +12,7 @@
 
 search_term = URI::encode('#todayilearned')
 
-SCHEDULER.every '10m', :first_in => 0 do |job|
+SCHEDULER.every '10m', first_in: 0 do |job|
   begin
     tweets = twitter.search("#{search_term}")
 
@@ -25,4 +25,4 @@
   rescue Twitter::Error
     puts "\e[33mFor the twitter widget to work, you need to put in your twitter API keys in the jobs/twitter.rb file.\e[0m"
   end
-end
\ No newline at end of file
+end
diff --git a/templates/project/tmp/pids/.empty_directory b/templates/project/tmp/pids/.empty_directory
new file mode 100644
index 0000000..3da7f49
--- /dev/null
+++ b/templates/project/tmp/pids/.empty_directory
@@ -0,0 +1 @@
+.empty_directory
\ No newline at end of file
diff --git a/test/app_test.rb b/test/app_test.rb
index 0eb6f3a..b23b98b 100644
--- a/test/app_test.rb
+++ b/test/app_test.rb
@@ -1,10 +1,16 @@
 require 'test_helper'
 require 'haml'
 
+class StreamStub < Array
+  def closed?
+    return false
+  end
+end
+
 class AppTest < Dashing::Test
   def setup
-    @connection = []
-    app.settings.connections = [@connection]
+    @connection = {out: StreamStub.new, mutex: Mutex.new, terminated: false}
+    app.settings.connections = [ @connection ]
     app.settings.auth_token = nil
     app.settings.default_dashboard = nil
     app.settings.history_file = File.join(Dir.tmpdir, 'history.yml')
@@ -48,9 +54,8 @@ def test_errors_out_when_no_dashboards_available
   def test_post_widgets_without_auth_token
     post '/widgets/some_widget', JSON.generate({value: 6})
     assert_equal 204, last_response.status
-
-    assert_equal 1, @connection.length
-    data = parse_data @connection[0]
+    assert_equal 1, @connection[:out].length
+    data = parse_data @connection[:out][0]
     assert_equal 6, data['value']
     assert_equal 'some_widget', data['id']
     assert data['updatedAt']
@@ -72,19 +77,15 @@ def test_get_events
     post '/widgets/some_widget', JSON.generate({value: 8})
     assert_equal 204, last_response.status
 
-    get '/events'
-    assert_equal 200, last_response.status
-    assert_equal 8, parse_data(@connection[0])['value']
+    assert_equal 8, parse_data(@connection[:out][0])['value']
   end
 
   def test_dashboard_events
     post '/dashboards/my_super_sweet_dashboard', JSON.generate({event: 'reload'})
     assert_equal 204, last_response.status
 
-    get '/events'
-    assert_equal 200, last_response.status
-    assert_equal 'dashboards', parse_event(@connection[0])
-    assert_equal 'reload', parse_data(@connection[0])['event']
+    assert_equal 'dashboards', parse_event(@connection[:out][0])
+    assert_equal 'reload', parse_data(@connection[:out][0])['event']
   end
 
   def test_get_dashboard
@@ -104,6 +105,8 @@ def test_page_title_set_correctly
   end
 
   def test_get_haml_dashboard
+    app.template_languages << :haml
+
     with_generated_project do |dir|
       File.write(File.join(dir, 'dashboards/hamltest.haml'), '.gridster')
       get '/hamltest'
@@ -113,6 +116,8 @@ def test_get_haml_dashboard
   end
 
   def test_get_haml_widget
+    app.template_languages << :haml
+
     with_generated_project do |dir|
       File.write(File.join(dir, 'widgets/clock/clock.haml'), '%h1 haml')
       File.unlink(File.join(dir, 'widgets/clock/clock.html'))
@@ -156,6 +161,11 @@ def with_generated_project
       app.settings.public_folder = File.join(dir, 'new_project/public')
       app.settings.views = File.join(dir, 'new_project/dashboards')
       app.settings.root = File.join(dir, 'new_project')
+
+      app.settings.raise_errors = true
+      app.settings.dump_errors = false
+      app.settings.show_exceptions = false
+
       yield app.settings.root
     end
   end
diff --git a/test/cli_test.rb b/test/cli_test.rb
index 4d82296..85191ce 100644
--- a/test/cli_test.rb
+++ b/test/cli_test.rb
@@ -101,34 +101,6 @@ def test_install_task_warns_when_gist_not_found
     assert_includes output, 'Could not find gist at '
   end
 
-  def test_start_task_starts_thin_with_default_port
-    command = 'bundle exec thin -R config.ru start -p 3030 '
-    @cli.stubs(:run_command).with(command).once
-    @cli.start
-  end
-
-  def test_start_task_starts_thin_with_specified_port
-    command = 'bundle exec thin -R config.ru start -p 2020'
-    @cli.stubs(:run_command).with(command).once
-    @cli.start('-p', '2020')
-  end
-
-  def test_start_task_supports_job_path_option
-    commands = [
-      'export JOB_PATH=other_spot; ',
-      'bundle exec thin -R config.ru start -p 3030 '
-    ]
-
-    @cli.stubs(:options).returns(job_path: 'other_spot')
-    @cli.stubs(:run_command).with(commands.join('')).once
-    @cli.start
-  end
-
-  def test_stop_task_stops_thin_server
-    @cli.stubs(:run_command).with('bundle exec thin stop')
-    @cli.stop
-  end
-
   def test_job_task_requires_job_file
     Dir.stubs(:pwd).returns('')
     @cli.stubs(:require_file).with('/jobs/special_job.rb').once