diff --git a/lib/is-isnt.js b/lib/is-isnt.js
index c5c5245..2164c43 100644
--- a/lib/is-isnt.js
+++ b/lib/is-isnt.js
@@ -1,4 +1,8 @@
 module.exports = (function ( Util ){
+
+	// For internal API
+	Util._isisnt = {};
+
 	Util.is = {};
 	Util.isnt = {};
 
@@ -9,7 +13,7 @@ module.exports = (function ( Util ){
 		return instance && instance.constructor ? instance.constructor !== ClassToEval : ! ( instance instanceof ClassToEval );
 	};
 
-	var addEvaluator = function ( ClassToEval, keys ) {
+	var register = Util._isisnt.register = function ( ClassToEval, keys ) {
 			if( ! ClassToEval ) return;
 
 			var isFn = function ( instance ) {
@@ -28,7 +32,7 @@ module.exports = (function ( Util ){
 				Util.isnt[ key ] = isntFn;
 			});
 		},
-		addCustomEvaluator = function ( keys, isFn, isntFn ) {
+		registerCustom = Util._isisnt.registerCustom = function ( keys, isFn, isntFn ) {
 
 			if( Util.isnt.function( isFn ) ) {
 				throw new TypeError("isFn must be a function");
@@ -52,19 +56,19 @@ module.exports = (function ( Util ){
 		};
 
 	// Default Javascript Classes
-	addEvaluator( Function, [ 'Function', 'function' ] );
-	addEvaluator( Array, [ 'Array', 'array' ] );
-	addEvaluator( Object, [ 'Object', 'object' ] );
-	addEvaluator( String, [ 'String', 'string' ] );
-	addEvaluator( Error, [ 'Error', 'error' ] );
+	register( Function, [ 'Function', 'function' ] );
+	register( Array, [ 'Array', 'array' ] );
+	register( Object, [ 'Object', 'object' ] );
+	register( String, [ 'String', 'string' ] );
+	register( Error, [ 'Error', 'error' ] );
 
 	// Default Browser Classes
 	if( typeof HTMLElement !== 'undefined' ) {
-		addEvaluator( HTMLElement, [ 'HTMLElement', 'HTMLelement' ] );
+		register( HTMLElement, [ 'HTMLElement', 'HTMLelement' ] );
 	}
 
 	// Custom evaluators
-	addCustomEvaluator( [ 'numeric', 'number', 'Number' ], function ( instance ) {
+	registerCustom( [ 'numeric', 'number', 'Number' ], function ( instance ) {
 		return typeof instance === 'number' || ! isNaN( parseInt( instance ) );
 	});