diff --git a/src/scripts/lib/switches-selectors.js b/src/scripts/lib/switches-selectors.js
new file mode 100644
index 0000000..5ae919f
--- /dev/null
+++ b/src/scripts/lib/switches-selectors.js
@@ -0,0 +1,35 @@
+var forEachEls = require("./foreach-els")
+
+var defaultSwitches = require("./switches")
+
+module.exports = function(switches, switchesOptions, selectors, fromEl, toEl, options) {
+  selectors.forEach(function(selector) {
+    var newEls = fromEl.querySelectorAll(selector)
+    var oldEls = toEl.querySelectorAll(selector)
+    if (this.log) {
+      this.log("Pjax switch", selector, newEls, oldEls)
+    }
+    if (newEls.length !== oldEls.length) {
+      // forEachEls(newEls, function(el) {
+      //   this.log("newEl", el, el.outerHTML)
+      // }, this)
+      // forEachEls(oldEls, function(el) {
+      //   this.log("oldEl", el, el.outerHTML)
+      // }, this)
+      throw "DOM doesn’t look the same on new loaded page: ’" + selector + "’ - new " + newEls.length + ", old " + oldEls.length
+    }
+
+    forEachEls(newEls, function(newEl, i) {
+      var oldEl = oldEls[i]
+      if (this.log) {
+        this.log("newEl", newEl, "oldEl", oldEl)
+      }
+      if (switches[selector]) {
+        switches[selector].bind(this)(oldEl, newEl, options, switchesOptions[selector])
+      }
+      else {
+        defaultSwitches.outerHTML.bind(this)(oldEl, newEl, options)
+      }
+    }, this)
+  }, this)
+}
diff --git a/src/scripts/lib/switches.js b/src/scripts/lib/switches.js
new file mode 100644
index 0000000..af14c43
--- /dev/null
+++ b/src/scripts/lib/switches.js
@@ -0,0 +1,110 @@
+module.exports = {
+  outerHTML: function(oldEl, newEl, options) {
+    oldEl.outerHTML = newEl.outerHTML
+    this.onSwitch()
+  },
+
+  innerHTML: function(oldEl, newEl, options) {
+    oldEl.innerHTML = newEl.innerHTML
+    oldEl.className = newEl.className
+    this.onSwitch()
+  },
+
+  sideBySide: function(oldEl, newEl, options, switchOptions) {
+    var forEach = Array.prototype.forEach
+    var elsToRemove = []
+    var elsToAdd = []
+    var fragToAppend = document.createDocumentFragment()
+    // height transition are shitty on safari
+    // so commented for now (until I found something ?)
+    //var relevantHeight = 0
+    var animationEventNames = "animationend webkitAnimationEnd MSAnimationEnd oanimationend"
+    var animatedElsNumber = 0
+    var sexyAnimationEnd = function(e) {
+          if (e.target != e.currentTarget) {
+            // end triggered by an animation on a child
+            return
+          }
+
+          animatedElsNumber--
+          if (animatedElsNumber <= 0 && elsToRemove) {
+            elsToRemove.forEach(function(el) {
+              // browsing quickly can make the el
+              // already removed by last page update ?
+              if (el.parentNode) {
+                el.parentNode.removeChild(el)
+              }
+            })
+
+            elsToAdd.forEach(function(el) {
+              el.className = el.className.replace(el.getAttribute("data-pjax-classes"), "")
+              el.removeAttribute("data-pjax-classes")
+              // Pjax.off(el, animationEventNames, sexyAnimationEnd, true)
+            })
+
+            elsToAdd = null // free memory
+            elsToRemove = null // free memory
+
+            // assume the height is now useless (avoid bug since there is overflow hidden on the parent)
+            // oldEl.style.height = "auto"
+
+            // this is to trigger some repaint (example: picturefill)
+            this.onSwitch()
+            //Pjax.trigger(window, "scroll")
+          }
+        }.bind(this)
+
+    // Force height to be able to trigger css animation
+    // here we get the relevant height
+    // oldEl.parentNode.appendChild(newEl)
+    // relevantHeight = newEl.getBoundingClientRect().height
+    // oldEl.parentNode.removeChild(newEl)
+    // oldEl.style.height = oldEl.getBoundingClientRect().height + "px"
+
+    switchOptions = switchOptions || {}
+
+    forEach.call(oldEl.childNodes, function(el) {
+      elsToRemove.push(el)
+      if (el.classList && !el.classList.contains("js-Pjax-remove")) {
+        // for fast switch, clean element that just have been added, & not cleaned yet.
+        if (el.hasAttribute("data-pjax-classes")) {
+          el.className = el.className.replace(el.getAttribute("data-pjax-classes"), "")
+          el.removeAttribute("data-pjax-classes")
+        }
+        el.classList.add("js-Pjax-remove")
+        if (switchOptions.callbacks && switchOptions.callbacks.removeElement) {
+          switchOptions.callbacks.removeElement(el)
+        }
+        if (switchOptions.classNames) {
+          el.className += " " + switchOptions.classNames.remove + " " + (options.backward ? switchOptions.classNames.backward : switchOptions.classNames.forward)
+        }
+        animatedElsNumber++
+        Pjax.on(el, animationEventNames, sexyAnimationEnd, true)
+      }
+    })
+
+    forEach.call(newEl.childNodes, function(el) {
+      if (el.classList) {
+        var addClasses = ""
+        if (switchOptions.classNames) {
+          addClasses = " js-Pjax-add " + switchOptions.classNames.add + " " + (options.backward ? switchOptions.classNames.forward : switchOptions.classNames.backward)
+        }
+        if (switchOptions.callbacks && switchOptions.callbacks.addElement) {
+          switchOptions.callbacks.addElement(el)
+        }
+        el.className += addClasses
+        el.setAttribute("data-pjax-classes", addClasses)
+        elsToAdd.push(el)
+        fragToAppend.appendChild(el)
+        animatedElsNumber++
+        Pjax.on(el, animationEventNames, sexyAnimationEnd, true)
+      }
+    })
+
+    // pass all className of the parent
+    oldEl.className = newEl.className
+    oldEl.appendChild(fragToAppend)
+
+    // oldEl.style.height = relevantHeight + "px"
+  }
+}
diff --git a/tests/scripts/lib/switch-selectors.js b/tests/scripts/lib/switch-selectors.js
new file mode 100644
index 0000000..0d5bb80
--- /dev/null
+++ b/tests/scripts/lib/switch-selectors.js
@@ -0,0 +1,9 @@
+var tape = require("tape")
+
+var switchesSelectors = require("../../../src/scripts/lib/switches-selectors.js")
+
+tape("test switchesSelectors", function(t) {
+  t.fail()
+
+  t.end()
+})