diff --git a/middleman-cli/lib/middleman-cli/build.rb b/middleman-cli/lib/middleman-cli/build.rb
index e3d098e7..df68c9e4 100644
--- a/middleman-cli/lib/middleman-cli/build.rb
+++ b/middleman-cli/lib/middleman-cli/build.rb
@@ -52,7 +52,7 @@ module Middleman::Cli
 
       ::Middleman::Logger.singleton(verbose, instrument)
 
-      ::Middleman::Util.instrument 'builder_setup' do
+      ::Middleman::Util.instrument 'builder.setup' do
         @app = ::Middleman::Application.new do
           config[:mode] = :build
           config[:environment] = env
@@ -67,7 +67,7 @@ module Middleman::Cli
         builder.on_build_event(&method(:on_event))
       end
 
-      ::Middleman::Util.instrument 'builder_run' do
+      ::Middleman::Util.instrument 'builder.run' do
         if builder.run!
           clean_directories! if options['clean']
           shell.say 'Project built successfully.'
diff --git a/middleman-core/lib/middleman-core/builder.rb b/middleman-core/lib/middleman-core/builder.rb
index ef289d42..4562dc6c 100644
--- a/middleman-core/lib/middleman-core/builder.rb
+++ b/middleman-core/lib/middleman-core/builder.rb
@@ -51,18 +51,31 @@ module Middleman
       @has_error = false
       @events = {}
 
-      @app.execute_callbacks(:before_build, [self])
+      ::Middleman::Util.instrument 'builder.before' do
+        @app.execute_callbacks(:before_build, [self])
+      end
 
-      queue_current_paths if @cleaning
+      ::Middleman::Util.instrument 'builder.queue' do
+        queue_current_paths if @cleaning
+      end
 
-      prerender_css
-      output_files
+      ::Middleman::Util.instrument 'builder.prerender' do
+        prerender_css
+      end
 
-      clean! if @cleaning
+      ::Middleman::Util.instrument 'builder.output' do
+        output_files
+      end
+
+      ::Middleman::Util.instrument 'builder.clean' do
+        clean! if @cleaning
+      end
 
       ::Middleman::Profiling.report('build')
 
-      @app.execute_callbacks(:after_build, [self])
+      ::Middleman::Util.instrument 'builder.after' do
+        @app.execute_callbacks(:after_build, [self])
+      end
 
       !@has_error
     end
@@ -73,14 +86,18 @@ module Middleman
     def prerender_css
       logger.debug '== Prerendering CSS'
 
-      css_files = @app.sitemap.resources
-                      .select { |resource| resource.ext == '.css' }
-                      .each(&method(:output_resource))
+      css_files = ::Middleman::Util.instrument 'builder.prerender.output' do
+        @app.sitemap.resources
+                        .select { |resource| resource.ext == '.css' }
+                        .each(&method(:output_resource))
+      end
 
-      # Double-check for compass sprites
-      if @app.files.find_new_files!.length > 0
-        logger.debug '== Checking for Compass sprites'
-        @app.sitemap.ensure_resource_list_updated!
+      ::Middleman::Util.instrument 'builder.prerender.check-files' do
+        # Double-check for compass sprites
+        if @app.files.find_new_files!.length > 0
+          logger.debug '== Checking for Compass sprites'
+          @app.sitemap.ensure_resource_list_updated!
+        end
       end
 
       css_files
@@ -92,11 +109,15 @@ module Middleman
     def output_files
       logger.debug '== Building files'
 
-      @app.sitemap.resources
-          .sort_by { |resource| SORT_ORDER.index(resource.ext) || 100 }
+      resources = @app.sitemap.resources
           .reject { |resource| resource.ext == '.css' }
-          .select { |resource| !@glob || File.fnmatch(@glob, resource.destination_path) }
-          .each(&method(:output_resource))
+          .sort_by { |resource| SORT_ORDER.index(resource.ext) || 100 }
+
+      if @glob
+        resources = resources.select { |resource| File.fnmatch(@glob, resource.destination_path) }
+      end
+
+      resources.each(&method(:output_resource))
     end
 
     # Figure out the correct event mode.
@@ -162,25 +183,29 @@ module Middleman
     # @return [void]
     Contract IsA['Middleman::Sitemap::Resource'] => Any
     def output_resource(resource)
-      output_file = @build_dir + resource.destination_path.gsub('%20', ' ')
+      output_file = nil
 
-      begin
-        if resource.binary?
-          export_file!(output_file, resource.file_descriptor[:full_path])
-        else
-          response = @rack.get(::URI.escape(resource.request_path))
+      ::Middleman::Util.instrument "builder.output.resource", path: File.basename(resource.destination_path) do
+        output_file = @build_dir + resource.destination_path.gsub('%20', ' ')
 
-          # If we get a response, save it to a tempfile.
-          if response.status == 200
-            export_file!(output_file, binary_encode(response.body))
+        begin
+          if resource.binary?
+            export_file!(output_file, resource.file_descriptor[:full_path])
           else
-            @has_error = true
-            trigger(:error, output_file, response.body)
+            response = @rack.get(::URI.escape(resource.request_path))
+
+            # If we get a response, save it to a tempfile.
+            if response.status == 200
+              export_file!(output_file, binary_encode(response.body))
+            else
+              @has_error = true
+              trigger(:error, output_file, response.body)
+            end
           end
+        rescue => e
+          @has_error = true
+          trigger(:error, output_file, "#{e}\n#{e.backtrace.join("\n")}")
         end
-      rescue => e
-        @has_error = true
-        trigger(:error, output_file, "#{e}\n#{e.backtrace.join("\n")}")
       end
 
       return unless @cleaning
diff --git a/middleman-core/lib/middleman-core/core_extensions/data.rb b/middleman-core/lib/middleman-core/core_extensions/data.rb
index 5f2a789f..cce997c6 100644
--- a/middleman-core/lib/middleman-core/core_extensions/data.rb
+++ b/middleman-core/lib/middleman-core/core_extensions/data.rb
@@ -57,6 +57,7 @@ module Middleman
           @app = app
           @data_file_matcher = data_file_matcher
           @local_data = {}
+          @local_data_enhanced = nil
           @local_sources = {}
           @callback_sources = {}
         end
@@ -117,6 +118,8 @@ module Middleman
           end
 
           data_branch[basename] = data
+
+          @local_data_enhanced = nil
         end
 
         # Remove a given file from the internal cache
@@ -137,6 +140,8 @@ module Middleman
           end
 
           data_branch.delete(basename) if data_branch.key?(basename)
+
+          @local_data_enhanced = nil
         end
 
         # Get a hash from either internal static data or a callback
@@ -151,8 +156,7 @@ module Middleman
             callbacks[path.to_s].call
           end
 
-          response = ::Middleman::Util.recursively_enhance(response)
-          response
+          ::Middleman::Util.recursively_enhance(response)
         end
 
         # "Magically" find namespaces of data if they exist
@@ -162,7 +166,8 @@ module Middleman
         def method_missing(path)
           if @local_data.key?(path.to_s)
             # Any way to cache this?
-            return ::Middleman::Util.recursively_enhance(@local_data[path.to_s])
+            @local_data_enhanced ||= ::Middleman::Util.recursively_enhance(@local_data)
+            return @local_data_enhanced[path.to_s]
           else
             result = data_for_path(path)
             return result if result
diff --git a/middleman-core/lib/middleman-core/file_renderer.rb b/middleman-core/lib/middleman-core/file_renderer.rb
index 67f9411f..64519be0 100644
--- a/middleman-core/lib/middleman-core/file_renderer.rb
+++ b/middleman-core/lib/middleman-core/file_renderer.rb
@@ -73,9 +73,10 @@ module Middleman
       # end
 
       # Render using Tilt
-      content = ::Middleman::Util.instrument 'render.tilt', path: path do
-        template.render(context, locs, &block)
-      end
+      # content = ::Middleman::Util.instrument 'render.tilt', path: path do
+      #   template.render(context, locs, &block)
+      # end
+      content = template.render(context, locs, &block)
 
       # Allow hooks to manipulate the result after render
       content = @app.callbacks_for(:after_render).reduce(content) do |sum, callback|
diff --git a/middleman-core/lib/middleman-core/logger.rb b/middleman-core/lib/middleman-core/logger.rb
index d1a1c402..30e28307 100644
--- a/middleman-core/lib/middleman-core/logger.rb
+++ b/middleman-core/lib/middleman-core/logger.rb
@@ -40,6 +40,7 @@ module Middleman
       return if @instrumenting.is_a?(String) && @instrumenting != 'instrument' && !message.include?(@instrumenting)
 
       evt = ::ActiveSupport::Notifications::Event.new(message, *args)
+      return unless evt.duration > 30
       info "== Instrument (#{evt.name.sub(/.middleman$/, '')}): #{evt.duration}ms\n#{args.last}"
     end
   end
diff --git a/middleman-core/lib/middleman-core/sitemap/resource.rb b/middleman-core/lib/middleman-core/sitemap/resource.rb
index b1f614e4..5d7b9969 100644
--- a/middleman-core/lib/middleman-core/sitemap/resource.rb
+++ b/middleman-core/lib/middleman-core/sitemap/resource.rb
@@ -66,6 +66,8 @@ module Middleman
         # Page are data that is exposed through this resource's data member.
         # Note: It is named 'page' for backwards compatibility with older MM.
         @metadata = { options: {}, locals: {}, page: {} }
+
+        @page_data = nil
       end
 
       # Whether this resource has a template file
@@ -91,6 +93,7 @@ module Middleman
       #   Note: It is named 'page' for backwards compatibility with older MM.
       Contract METADATA_HASH => METADATA_HASH
       def add_metadata(meta={})
+        @page_data = nil
         @metadata.deep_merge!(meta)
       end
 
@@ -98,7 +101,7 @@ module Middleman
       # @return [Hash]
       Contract RespondTo[:indifferent_access?]
       def data
-        ::Middleman::Util.recursively_enhance(metadata[:page])
+        @page_data ||= ::Middleman::Util.recursively_enhance(metadata[:page])
       end
 
       # Options about how this resource is rendered, such as its :layout,
@@ -129,7 +132,6 @@ module Middleman
       def render(opts={}, locs={})
         return ::Middleman::FileRenderer.new(@app, file_descriptor[:full_path].to_s).template_data_for_file unless template?
 
-        # ::Middleman::Util.instrument 'render.resource', path: file_descriptor[:full_path].to_s, destination_path: destination_path do
         md   = metadata
         opts = md[:options].deep_merge(opts)
         locs = md[:locals].deep_merge(locs)
@@ -140,7 +142,6 @@ module Middleman
 
         renderer = ::Middleman::TemplateRenderer.new(@app, file_descriptor[:full_path].to_s)
         renderer.render(locs, opts)
-        # end
       end
 
       # A path without the directory index - so foo/index.html becomes
diff --git a/middleman-core/lib/middleman-core/sources/source_watcher.rb b/middleman-core/lib/middleman-core/sources/source_watcher.rb
index 0c7356c2..e6ad077c 100644
--- a/middleman-core/lib/middleman-core/sources/source_watcher.rb
+++ b/middleman-core/lib/middleman-core/sources/source_watcher.rb
@@ -185,9 +185,7 @@ module Middleman
       new_files = ::Middleman::Util.all_files_under(@directory.to_s)
                                    .reject { |p| @files.key?(p) }
 
-      update(new_files, [])
-
-      new_files
+      update(new_files, []).flatten.map { |s| s[:full_path] }
     end
 
     # Manually trigger update events.
@@ -198,14 +196,14 @@ module Middleman
       updated = ::Middleman::Util.all_files_under(@directory.to_s)
       removed = @files.keys.reject { |p| updated.include?(p) }
 
-      update(updated, removed)
+      result = update(updated, removed)
 
       if @waiting_for_existence && @directory.exist?
         @waiting_for_existence = false
         listen!
       end
 
-      updated + removed
+      result.flatten.map { |s| s[:full_path] }
     end
 
     # Work around this bug: http://bugs.ruby-lang.org/issues/4521
@@ -238,7 +236,7 @@ module Middleman
     #
     # @param [String, Pathname] path The updated file path.
     # @return [void]
-    Contract ArrayOf[Pathname], ArrayOf[Pathname] => Any
+    Contract ArrayOf[Pathname], ArrayOf[Pathname] => ArrayOf[ArrayOf[IsA['Middleman::SourceFile']]]
     def update(updated_paths, removed_paths)
       valid_updates = updated_paths
                       .map { |p| @files[p] || path_to_source_file(p, @directory, @type, @options[:destination_dir]) }
@@ -271,6 +269,8 @@ module Middleman
                           valid_removes,
                           self
                         ]) unless valid_updates.empty? && valid_removes.empty?
+
+      [valid_updates, valid_removes]
     end
 
     # Convert a path to a file resprentation.
diff --git a/middleman-core/lib/middleman-core/template_renderer.rb b/middleman-core/lib/middleman-core/template_renderer.rb
index 4af4ce14..1930d434 100644
--- a/middleman-core/lib/middleman-core/template_renderer.rb
+++ b/middleman-core/lib/middleman-core/template_renderer.rb
@@ -133,12 +133,21 @@ module Middleman
       # Add extension helpers to context.
       @app.extensions.add_exposed_to_context(context)
 
-      content = _render_with_all_renderers(path, locs, context, opts, &block)
+      content = ::Middleman::Util.instrument 'builder.output.resource.render-template', path: File.basename(path) do
+        _render_with_all_renderers(path, locs, context, opts, &block)
+      end
 
       # If we need a layout and have a layout, use it
-      if layout_file = fetch_layout(engine, options)
-        layout_renderer = ::Middleman::FileRenderer.new(@app, layout_file[:relative_path].to_s)
-        content = layout_renderer.render(locals, options, context) { content }
+      layout_file = fetch_layout(engine, options)
+      if layout_file
+        content = ::Middleman::Util.instrument 'builder.output.resource.render-layout', path: File.basename(layout_file[:relative_path].to_s) do
+          if layout_file = fetch_layout(engine, options)
+            layout_renderer = ::Middleman::FileRenderer.new(@app, layout_file[:relative_path].to_s)
+            layout_renderer.render(locals, options, context) { content }
+          else
+            content
+          end
+        end
       end
 
       # Return result
diff --git a/middleman-core/lib/middleman-core/util.rb b/middleman-core/lib/middleman-core/util.rb
index ae15e3ec..a2cd1eef 100644
--- a/middleman-core/lib/middleman-core/util.rb
+++ b/middleman-core/lib/middleman-core/util.rb
@@ -98,7 +98,7 @@ module Middleman
     # @private
     # @param [Hash] data Normal hash
     # @return [Hash]
-    Contract Maybe[Hash] => Maybe[Or[Array, EnhancedHash]]
+    Contract Any => Maybe[Or[Array, EnhancedHash]]
     def recursively_enhance(obj)
       if obj.is_a? ::Array
         obj.map { |e| recursively_enhance(e) }
@@ -480,6 +480,8 @@ module Middleman
     # @return [String]
     Contract String => ArrayOf[String]
     def collect_extensions(path)
+      return [] if File.basename(path).start_with?('.')
+
       result = []
 
       step_through_extensions(path) { |e| result << e }
@@ -495,6 +497,8 @@ module Middleman
     # @return [Middleman::SourceFile] All related file paths, not including the source file paths.
     Contract ::Middleman::Application, ArrayOf[Pathname] => ArrayOf[::Middleman::SourceFile]
     def find_related_files(app, files)
+      return [] if files.empty?
+
       all_extensions = files.flat_map { |f| collect_extensions(f.to_s) }
 
       sass_type_aliasing = ['.scss', '.sass']