diff --git a/src/generators/dom/index.ts b/src/generators/dom/index.ts
index 776cf1ab0b..e103f428cf 100644
--- a/src/generators/dom/index.ts
+++ b/src/generators/dom/index.ts
@@ -375,6 +375,7 @@ export default function dom(
 			if (sigil === '@') {
 				if (name in shared) {
 					if (options.dev && `${name}Dev` in shared) name = `${name}Dev`;
+					else if (options.immutable && `${name}Immutable` in shared) name = `${name}Immutable`;
 					usedHelpers.add(name);
 				}
 
diff --git a/src/interfaces.ts b/src/interfaces.ts
index 9773d330d3..82de8cd047 100644
--- a/src/interfaces.ts
+++ b/src/interfaces.ts
@@ -52,6 +52,7 @@ export interface CompileOptions {
 	cssOutputFilename?: string;
 
 	dev?: boolean;
+	immutable?: boolean;
 	shared?: boolean | string;
 	cascade?: boolean;
 	hydratable?: boolean;
diff --git a/src/shared/index.js b/src/shared/index.js
index ef160ebf07..ec8706be6d 100644
--- a/src/shared/index.js
+++ b/src/shared/index.js
@@ -26,7 +26,25 @@ export function destroyDev(detach) {
 }
 
 export function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
+}
+
+export function differsImmutable(a, b) {
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b;
 }
 
 export function dispatchObservers(component, group, changed, newState, oldState) {
@@ -165,6 +183,27 @@ export function _set(newState) {
 	}
 }
 
+export function _setImmutable(newState) {
+	var oldState = this._state,
+		changed = {},
+		dirty = false;
+
+	for (var key in newState) {
+		if (differsImmutable(newState[key], oldState[key])) changed[key] = dirty = true;
+	}
+	if (!dirty) return;
+
+	this._state = assign({}, oldState, newState);
+	this._recompute(changed, this._state);
+	if (this._bind) this._bind(changed, this._state);
+
+	if (this._fragment) {
+		dispatchObservers(this, this._observers.pre, changed, this._state, oldState);
+		this._fragment.p(changed, this._state);
+		dispatchObservers(this, this._observers.post, changed, this._state, oldState);
+	}
+}
+
 export function setDev(newState) {
 	if (typeof newState !== 'object') {
 		throw new Error(
diff --git a/store.js b/store.js
index f31c659080..853d36a52a 100644
--- a/store.js
+++ b/store.js
@@ -2,12 +2,13 @@ import {
 	assign,
 	blankObject,
 	differs,
+	differsImmutable,
 	dispatchObservers,
 	get,
 	observe
 } from './shared.js';
 
-function Store(state) {
+function Store(state, options) {
 	this._observers = { pre: blankObject(), post: blankObject() };
 	this._changeHandlers = [];
 	this._dependents = [];
@@ -16,6 +17,7 @@ function Store(state) {
 	this._sortedComputedProperties = [];
 
 	this._state = assign({}, state);
+	this._differs = options && options.immutable ? differsImmutable : differs;
 }
 
 assign(Store.prototype, {
@@ -88,7 +90,7 @@ assign(Store.prototype, {
 
 				if (dirty) {
 					var newValue = fn.apply(null, values);
-					if (differs(newValue, value)) {
+					if (store._differs(newValue, value)) {
 						value = newValue;
 						changed[key] = true;
 						state[key] = value;
@@ -124,7 +126,7 @@ assign(Store.prototype, {
 
 		for (var key in newState) {
 			if (this._computed[key]) throw new Error("'" + key + "' is a read-only property");
-			if (differs(newState[key], oldState[key])) changed[key] = dirty = true;
+			if (this._differs(newState[key], oldState[key])) changed[key] = dirty = true;
 		}
 		if (!dirty) return;
 
diff --git a/test/js/samples/collapses-text-around-comments/expected-bundle.js b/test/js/samples/collapses-text-around-comments/expected-bundle.js
index 59cd2de125..ffc75c872c 100644
--- a/test/js/samples/collapses-text-around-comments/expected-bundle.js
+++ b/test/js/samples/collapses-text-around-comments/expected-bundle.js
@@ -52,7 +52,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/component-static/expected-bundle.js b/test/js/samples/component-static/expected-bundle.js
index 708ef5be95..970b8e139a 100644
--- a/test/js/samples/component-static/expected-bundle.js
+++ b/test/js/samples/component-static/expected-bundle.js
@@ -28,7 +28,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/computed-collapsed-if/expected-bundle.js b/test/js/samples/computed-collapsed-if/expected-bundle.js
index b39f95a77b..e9285f3bc0 100644
--- a/test/js/samples/computed-collapsed-if/expected-bundle.js
+++ b/test/js/samples/computed-collapsed-if/expected-bundle.js
@@ -28,7 +28,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/css-media-query/expected-bundle.js b/test/js/samples/css-media-query/expected-bundle.js
index 91662053a4..6ccc9200d5 100644
--- a/test/js/samples/css-media-query/expected-bundle.js
+++ b/test/js/samples/css-media-query/expected-bundle.js
@@ -48,7 +48,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/css-shadow-dom-keyframes/expected-bundle.js b/test/js/samples/css-shadow-dom-keyframes/expected-bundle.js
index 03e5cef1e2..4948afea4d 100644
--- a/test/js/samples/css-shadow-dom-keyframes/expected-bundle.js
+++ b/test/js/samples/css-shadow-dom-keyframes/expected-bundle.js
@@ -40,7 +40,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/deconflict-globals/expected-bundle.js b/test/js/samples/deconflict-globals/expected-bundle.js
index ba22542c4b..6733b68767 100644
--- a/test/js/samples/deconflict-globals/expected-bundle.js
+++ b/test/js/samples/deconflict-globals/expected-bundle.js
@@ -28,7 +28,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/do-use-dataset/expected-bundle.js b/test/js/samples/do-use-dataset/expected-bundle.js
index 2079e6607c..442afd002e 100644
--- a/test/js/samples/do-use-dataset/expected-bundle.js
+++ b/test/js/samples/do-use-dataset/expected-bundle.js
@@ -44,7 +44,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/dont-use-dataset-in-legacy/expected-bundle.js b/test/js/samples/dont-use-dataset-in-legacy/expected-bundle.js
index efcfcc8f30..3b5681f2ca 100644
--- a/test/js/samples/dont-use-dataset-in-legacy/expected-bundle.js
+++ b/test/js/samples/dont-use-dataset-in-legacy/expected-bundle.js
@@ -48,7 +48,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/dont-use-dataset-in-svg/expected-bundle.js b/test/js/samples/dont-use-dataset-in-svg/expected-bundle.js
index cf43bbd130..242ac51828 100644
--- a/test/js/samples/dont-use-dataset-in-svg/expected-bundle.js
+++ b/test/js/samples/dont-use-dataset-in-svg/expected-bundle.js
@@ -48,7 +48,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/each-block-changed-check/expected-bundle.js b/test/js/samples/each-block-changed-check/expected-bundle.js
index e35826e354..ca09f3774f 100644
--- a/test/js/samples/each-block-changed-check/expected-bundle.js
+++ b/test/js/samples/each-block-changed-check/expected-bundle.js
@@ -60,7 +60,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/event-handlers-custom/expected-bundle.js b/test/js/samples/event-handlers-custom/expected-bundle.js
index 43db3035a3..f9e32a0256 100644
--- a/test/js/samples/event-handlers-custom/expected-bundle.js
+++ b/test/js/samples/event-handlers-custom/expected-bundle.js
@@ -40,7 +40,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/head-no-whitespace/expected-bundle.js b/test/js/samples/head-no-whitespace/expected-bundle.js
index 91f894bc30..62aac217d5 100644
--- a/test/js/samples/head-no-whitespace/expected-bundle.js
+++ b/test/js/samples/head-no-whitespace/expected-bundle.js
@@ -40,7 +40,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/if-block-no-update/expected-bundle.js b/test/js/samples/if-block-no-update/expected-bundle.js
index b309a25e96..681edc072e 100644
--- a/test/js/samples/if-block-no-update/expected-bundle.js
+++ b/test/js/samples/if-block-no-update/expected-bundle.js
@@ -44,7 +44,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/if-block-simple/expected-bundle.js b/test/js/samples/if-block-simple/expected-bundle.js
index 5084639f4b..9ce6331f44 100644
--- a/test/js/samples/if-block-simple/expected-bundle.js
+++ b/test/js/samples/if-block-simple/expected-bundle.js
@@ -44,7 +44,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/inline-style-optimized-multiple/expected-bundle.js b/test/js/samples/inline-style-optimized-multiple/expected-bundle.js
index 753d61db71..9077eea9d7 100644
--- a/test/js/samples/inline-style-optimized-multiple/expected-bundle.js
+++ b/test/js/samples/inline-style-optimized-multiple/expected-bundle.js
@@ -44,7 +44,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/inline-style-optimized-url/expected-bundle.js b/test/js/samples/inline-style-optimized-url/expected-bundle.js
index cf360881b1..7277ff587a 100644
--- a/test/js/samples/inline-style-optimized-url/expected-bundle.js
+++ b/test/js/samples/inline-style-optimized-url/expected-bundle.js
@@ -44,7 +44,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/inline-style-optimized/expected-bundle.js b/test/js/samples/inline-style-optimized/expected-bundle.js
index 38024df4ff..9b3f41768f 100644
--- a/test/js/samples/inline-style-optimized/expected-bundle.js
+++ b/test/js/samples/inline-style-optimized/expected-bundle.js
@@ -44,7 +44,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/inline-style-unoptimized/expected-bundle.js b/test/js/samples/inline-style-unoptimized/expected-bundle.js
index 320c733a43..f1a5a53d7f 100644
--- a/test/js/samples/inline-style-unoptimized/expected-bundle.js
+++ b/test/js/samples/inline-style-unoptimized/expected-bundle.js
@@ -44,7 +44,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/input-without-blowback-guard/expected-bundle.js b/test/js/samples/input-without-blowback-guard/expected-bundle.js
index eacaca85a6..b32377763e 100644
--- a/test/js/samples/input-without-blowback-guard/expected-bundle.js
+++ b/test/js/samples/input-without-blowback-guard/expected-bundle.js
@@ -48,7 +48,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/legacy-input-type/expected-bundle.js b/test/js/samples/legacy-input-type/expected-bundle.js
index 7b730f08d9..1dbd32f619 100644
--- a/test/js/samples/legacy-input-type/expected-bundle.js
+++ b/test/js/samples/legacy-input-type/expected-bundle.js
@@ -46,7 +46,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/legacy-quote-class/expected-bundle.js b/test/js/samples/legacy-quote-class/expected-bundle.js
index 499a82c46e..0b203fb4b6 100644
--- a/test/js/samples/legacy-quote-class/expected-bundle.js
+++ b/test/js/samples/legacy-quote-class/expected-bundle.js
@@ -63,7 +63,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/media-bindings/expected-bundle.js b/test/js/samples/media-bindings/expected-bundle.js
index bbd56d8123..ec971167be 100644
--- a/test/js/samples/media-bindings/expected-bundle.js
+++ b/test/js/samples/media-bindings/expected-bundle.js
@@ -56,7 +56,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/non-imported-component/expected-bundle.js b/test/js/samples/non-imported-component/expected-bundle.js
index f8e0722db7..46de1d757e 100644
--- a/test/js/samples/non-imported-component/expected-bundle.js
+++ b/test/js/samples/non-imported-component/expected-bundle.js
@@ -42,7 +42,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/onrender-onteardown-rewritten/expected-bundle.js b/test/js/samples/onrender-onteardown-rewritten/expected-bundle.js
index e53dd0de5e..b65e0bfc2a 100644
--- a/test/js/samples/onrender-onteardown-rewritten/expected-bundle.js
+++ b/test/js/samples/onrender-onteardown-rewritten/expected-bundle.js
@@ -28,7 +28,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/setup-method/expected-bundle.js b/test/js/samples/setup-method/expected-bundle.js
index 58ee3a67a0..80bb847692 100644
--- a/test/js/samples/setup-method/expected-bundle.js
+++ b/test/js/samples/setup-method/expected-bundle.js
@@ -28,7 +28,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/svg-title/expected-bundle.js b/test/js/samples/svg-title/expected-bundle.js
index 12f06bcf92..1ee4d64a48 100644
--- a/test/js/samples/svg-title/expected-bundle.js
+++ b/test/js/samples/svg-title/expected-bundle.js
@@ -48,7 +48,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/title/expected-bundle.js b/test/js/samples/title/expected-bundle.js
index 6eb3471b5b..454a1fad0e 100644
--- a/test/js/samples/title/expected-bundle.js
+++ b/test/js/samples/title/expected-bundle.js
@@ -28,7 +28,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/use-elements-as-anchors/expected-bundle.js b/test/js/samples/use-elements-as-anchors/expected-bundle.js
index e2ee1e61fb..9ac57fe215 100644
--- a/test/js/samples/use-elements-as-anchors/expected-bundle.js
+++ b/test/js/samples/use-elements-as-anchors/expected-bundle.js
@@ -52,7 +52,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {
diff --git a/test/js/samples/window-binding-scroll/expected-bundle.js b/test/js/samples/window-binding-scroll/expected-bundle.js
index a8a932c8b7..457f6d55ea 100644
--- a/test/js/samples/window-binding-scroll/expected-bundle.js
+++ b/test/js/samples/window-binding-scroll/expected-bundle.js
@@ -48,7 +48,14 @@ function destroy(detach) {
 }
 
 function differs(a, b) {
-	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+	if (a == null || b == null) return a !== b;
+	if (a.constructor !== b.constructor) return true;
+	if (a.valueOf && b.valueOf) {
+		a = a.valueOf();
+		b = b.valueOf();
+	}
+	if (typeof a === 'number' && isNaN(a) && isNaN(b)) return false;
+	return a !== b || typeof a === 'object' || typeof a === 'function';
 }
 
 function dispatchObservers(component, group, changed, newState, oldState) {