diff --git a/Gulpfile.babel.js b/Gulpfile.babel.js
index 5fefcc60a..1bcc625b6 100755
--- a/Gulpfile.babel.js
+++ b/Gulpfile.babel.js
@@ -90,9 +90,16 @@ gulp.src = (...glob) => {
 
 /*
  * Helper function to load a task
+ *
+ * This function returns a callback that will require the task with the given
+ * name and execute the function that is returned by this task. It omits the
+ * need to load all tasks upfront, speeding up the build a gazillion times.
  */
 const load = task => {
-  return require(`./${config.lib}/tasks/${task}`)(gulp, config, args)
+  return done => {
+    return require(`./${config.lib}/tasks/${task}`)
+      .call(gulp, gulp, config, args)(done)
+  }
 }
 
 /* ----------------------------------------------------------------------------
@@ -102,26 +109,26 @@ const load = task => {
 /*
  * Copy favicon
  */
-gulp.task("assets:images:build:ico",
+gulp.task("assets:images:build:ico", [
+  args.clean ? "assets:images:clean" : null
+].filter(t => t),
   load("assets/images/build/ico"))
 
 /*
  * Copy and minify vector graphics
  */
-gulp.task("assets:images:build:svg",
+gulp.task("assets:images:build:svg", [
+  args.clean ? "assets:images:clean" : null
+].filter(t => t),
   load("assets/images/build/svg"))
 
 /*
  * Copy images
  */
-gulp.task("assets:images:build", args.clean ? [
-  "assets:images:clean"
-] : [], () => {
-  return gulp.start([
-    "assets:images:build:ico",
-    "assets:images:build:svg"
-  ])
-})
+gulp.task("assets:images:build", [
+  "assets:images:build:ico",
+  "assets:images:build:svg"
+])
 
 /*
  * Clean images generated by build
@@ -136,29 +143,30 @@ gulp.task("assets:images:clean",
 /*
  * Build application logic
  */
-gulp.task("assets:javascripts:build:application",
+
+gulp.task("assets:javascripts:build:application", [
+  args.clean ? "assets:javascripts:clean" : null,
+  args.lint ? "assets:javascripts:lint" : null
+].filter(t => t),
   load("assets/javascripts/build/application"))
 
 /*
  * Build custom modernizr
  */
 gulp.task("assets:javascripts:build:modernizr", [
-  "assets:stylesheets:build"
-], load("assets/javascripts/build/modernizr"))
+  "assets:stylesheets:build",
+  args.clean ? "assets:javascripts:clean" : null,
+  args.lint ? "assets:javascripts:lint" : null
+].filter(t => t),
+  load("assets/javascripts/build/modernizr"))
 
 /*
  * Build application logic and modernizr
  */
-gulp.task("assets:javascripts:build", (args.clean ? [
-  "assets:javascripts:clean"
-] : []).concat(args.lint ? [
-  "assets:javascripts:lint"
-] : []), () => {
-  return gulp.start([
-    "assets:javascripts:build:application",
-    "assets:javascripts:build:modernizr"
-  ])
-})
+gulp.task("assets:javascripts:build", [
+  "assets:javascripts:build:application",
+  "assets:javascripts:build:modernizr"
+])
 
 /*
  * Clean JavaScript generated by build
@@ -179,11 +187,10 @@ gulp.task("assets:javascripts:lint",
 /*
  * Build stylesheets from SASS source
  */
-gulp.task("assets:stylesheets:build", (args.clean ? [
-  "assets:stylesheets:clean"
-] : []).concat(args.lint ? [
-  "assets:stylesheets:lint"
-] : []),
+gulp.task("assets:stylesheets:build", [
+  args.clean ? "assets:stylesheets:clean" : null,
+  args.lint ? "assets:stylesheets:lint" : null
+].filter(t => t),
   load("assets/stylesheets/build"))
 
 /*
@@ -227,13 +234,14 @@ gulp.task("assets:clean", [
 /*
  * Minify views
  */
-gulp.task("views:build", (args.revision ? [
-  "assets:images:build",
-  "assets:stylesheets:build",
-  "assets:javascripts:build"
-] : []).concat(args.clean ? [
-  "views:clean"
-] : []), load("views/build"))
+
+gulp.task("views:build", [
+  args.revision ? "assets:images:build" : null,
+  args.revision ? "assets:stylesheets:build" : null,
+  args.revision ? "assets:javascripts:build" : null,
+  args.clean ? "views:clean" : null
+].filter(t => t),
+  load("views/build"))
 
 /*
  * Clean views
@@ -252,7 +260,8 @@ gulp.task("mkdocs:build", [
   "assets:build",
   "views:build",
   "mkdocs:clean"
-], load("mkdocs/build"))
+],
+  load("mkdocs/build"))
 
 /*
  * Clean documentation build
@@ -285,10 +294,9 @@ gulp.task("tests:unit:watch",
  */
 gulp.task("build", [
   "assets:build",
-  "views:build"
-].concat(args.mkdocs
-  ? "mkdocs:build"
-  : []))
+  "views:build",
+  args.mkdocs ? "mkdocs:build" : null
+].filter(f => f))
 
 /*
  * Clean assets and documentation
diff --git a/lib/tasks/views/clean.js b/lib/tasks/views/clean.js
index 95301e127..3a2dab289 100644
--- a/lib/tasks/views/clean.js
+++ b/lib/tasks/views/clean.js
@@ -29,7 +29,7 @@ import vinyl from "vinyl-paths"
 
 export default (gulp, config) => {
   return () => {
-    return gulp.src(`${config.views.build}/**/*.html`)
+    return gulp.src(`${config.views.build}/**/*.{html,py}`)
       .pipe(vinyl(clean))
   }
 }