diff --git a/dist/pacto.model.cjs.js b/dist/pacto.model.cjs.js
new file mode 100644
index 0000000..b85acaf
--- /dev/null
+++ b/dist/pacto.model.cjs.js
@@ -0,0 +1,305 @@
+'use strict';
+
+Object.defineProperty(exports, '__esModule', { value: true });
+
+var pacto = require('pacto');
+
+function _classCallCheck(instance, Constructor) {
+  if (!(instance instanceof Constructor)) {
+    throw new TypeError("Cannot call a class as a function");
+  }
+}
+
+function _defineProperties(target, props) {
+  for (var i = 0; i < props.length; i++) {
+    var descriptor = props[i];
+    descriptor.enumerable = descriptor.enumerable || false;
+    descriptor.configurable = true;
+    if ("value" in descriptor) descriptor.writable = true;
+    Object.defineProperty(target, descriptor.key, descriptor);
+  }
+}
+
+function _createClass(Constructor, protoProps, staticProps) {
+  if (protoProps) _defineProperties(Constructor.prototype, protoProps);
+  if (staticProps) _defineProperties(Constructor, staticProps);
+  return Constructor;
+}
+
+function _defineProperty(obj, key, value) {
+  if (key in obj) {
+    Object.defineProperty(obj, key, {
+      value: value,
+      enumerable: true,
+      configurable: true,
+      writable: true
+    });
+  } else {
+    obj[key] = value;
+  }
+
+  return obj;
+}
+
+function ownKeys(object, enumerableOnly) {
+  var keys = Object.keys(object);
+
+  if (Object.getOwnPropertySymbols) {
+    var symbols = Object.getOwnPropertySymbols(object);
+    if (enumerableOnly) symbols = symbols.filter(function (sym) {
+      return Object.getOwnPropertyDescriptor(object, sym).enumerable;
+    });
+    keys.push.apply(keys, symbols);
+  }
+
+  return keys;
+}
+
+function _objectSpread2(target) {
+  for (var i = 1; i < arguments.length; i++) {
+    var source = arguments[i] != null ? arguments[i] : {};
+
+    if (i % 2) {
+      ownKeys(Object(source), true).forEach(function (key) {
+        _defineProperty(target, key, source[key]);
+      });
+    } else if (Object.getOwnPropertyDescriptors) {
+      Object.defineProperties(target, Object.getOwnPropertyDescriptors(source));
+    } else {
+      ownKeys(Object(source)).forEach(function (key) {
+        Object.defineProperty(target, key, Object.getOwnPropertyDescriptor(source, key));
+      });
+    }
+  }
+
+  return target;
+}
+
+function _inherits(subClass, superClass) {
+  if (typeof superClass !== "function" && superClass !== null) {
+    throw new TypeError("Super expression must either be null or a function");
+  }
+
+  subClass.prototype = Object.create(superClass && superClass.prototype, {
+    constructor: {
+      value: subClass,
+      writable: true,
+      configurable: true
+    }
+  });
+  if (superClass) _setPrototypeOf(subClass, superClass);
+}
+
+function _getPrototypeOf(o) {
+  _getPrototypeOf = Object.setPrototypeOf ? Object.getPrototypeOf : function _getPrototypeOf(o) {
+    return o.__proto__ || Object.getPrototypeOf(o);
+  };
+  return _getPrototypeOf(o);
+}
+
+function _setPrototypeOf(o, p) {
+  _setPrototypeOf = Object.setPrototypeOf || function _setPrototypeOf(o, p) {
+    o.__proto__ = p;
+    return o;
+  };
+
+  return _setPrototypeOf(o, p);
+}
+
+function _isNativeReflectConstruct() {
+  if (typeof Reflect === "undefined" || !Reflect.construct) return false;
+  if (Reflect.construct.sham) return false;
+  if (typeof Proxy === "function") return true;
+
+  try {
+    Date.prototype.toString.call(Reflect.construct(Date, [], function () {}));
+    return true;
+  } catch (e) {
+    return false;
+  }
+}
+
+function _assertThisInitialized(self) {
+  if (self === void 0) {
+    throw new ReferenceError("this hasn't been initialised - super() hasn't been called");
+  }
+
+  return self;
+}
+
+function _possibleConstructorReturn(self, call) {
+  if (call && (typeof call === "object" || typeof call === "function")) {
+    return call;
+  }
+
+  return _assertThisInitialized(self);
+}
+
+function _createSuper(Derived) {
+  return function () {
+    var Super = _getPrototypeOf(Derived),
+        result;
+
+    if (_isNativeReflectConstruct()) {
+      var NewTarget = _getPrototypeOf(this).constructor;
+
+      result = Reflect.construct(Super, arguments, NewTarget);
+    } else {
+      result = Super.apply(this, arguments);
+    }
+
+    return _possibleConstructorReturn(this, result);
+  };
+}
+
+var __refs = new WeakMap();
+
+var Model = /*#__PURE__*/function (_EventEmitter) {
+  _inherits(Model, _EventEmitter);
+
+  var _super = _createSuper(Model);
+
+  function Model() {
+    var _this;
+
+    var props = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : {};
+
+    _classCallCheck(this, Model);
+
+    _this = _super.call(this);
+    props = _objectSpread2({}, _this.defaults, {}, props);
+    var handler = {
+      set: function set(target, prop, value) {
+        var isChanged = target[prop] !== value;
+        target[prop] = value;
+
+        if (isChanged) {
+          _this.trigger('change', {
+            prop: prop,
+            value: value
+          });
+        }
+
+        return true;
+      }
+    },
+        proxy = new Proxy(props, handler);
+
+    __refs.set(_assertThisInitialized(_this), proxy);
+
+    return _this;
+  }
+
+  _createClass(Model, [{
+    key: "defaults",
+    get: function get() {
+      return null;
+    }
+  }, {
+    key: "props",
+    get: function get() {
+      return __refs.get(this);
+    }
+  }]);
+
+  return Model;
+}(pacto.EventEmitter);
+
+var __refs$1 = new WeakMap();
+
+var Collection = /*#__PURE__*/function (_EventEmitter) {
+  _inherits(Collection, _EventEmitter);
+
+  var _super = _createSuper(Collection);
+
+  function Collection() {
+    var _this;
+
+    var models = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : [];
+
+    _classCallCheck(this, Collection);
+
+    _this = _super.call(this);
+
+    var enshureIsModel = function enshureIsModel(model) {
+      return model instanceof Model ? model : new _this.Model(model);
+    },
+        handler = {
+      get: function get(target, property) {
+        var method = target[property];
+
+        if (typeof method === 'function') {
+          return function () {
+            for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
+              args[_key] = arguments[_key];
+            }
+
+            var isChanged = false,
+                result;
+
+            switch (property) {
+              case 'pop':
+              case 'reverse':
+              case 'shift':
+              case 'sort':
+                isChanged = true;
+                break;
+
+              case 'fill':
+                isChanged = true;
+                args[0] = enshureIsModel(args[0]);
+                break;
+
+              case 'push':
+              case 'unshift':
+                isChanged = true;
+                args = args.map(enshureIsModel);
+                break;
+
+              case 'splice':
+                isChanged = true;
+                args = args.map(function (arg, index) {
+                  return index > 1 ? enshureIsModel(arg) : arg;
+                });
+                break;
+            }
+
+            result = method.apply(target, args);
+
+            if (isChanged) {
+              _this.trigger('change', {
+                method: property
+              });
+            }
+
+            return result;
+          };
+        }
+
+        return method;
+      }
+    },
+        proxy = new Proxy(models.map(enshureIsModel), handler);
+
+    __refs$1.set(_assertThisInitialized(_this), proxy);
+
+    return _this;
+  }
+
+  _createClass(Collection, [{
+    key: "Model",
+    get: function get() {
+      return Model;
+    }
+  }, {
+    key: "models",
+    get: function get() {
+      return __refs$1.get(this);
+    }
+  }]);
+
+  return Collection;
+}(pacto.EventEmitter);
+
+exports.Collection = Collection;
+exports.Model = Model;
diff --git a/dist/pacto.model.esm.js b/dist/pacto.model.esm.js
new file mode 100644
index 0000000..ed0e6ef
--- /dev/null
+++ b/dist/pacto.model.esm.js
@@ -0,0 +1,118 @@
+import { EventEmitter } from 'pacto';
+
+const __refs = new WeakMap();
+
+
+class Model extends EventEmitter {
+
+	constructor(props = {}) {
+		super();
+		props = {...this.defaults, ...props};
+
+		const
+			handler = {
+				set: (target, prop, value) => {
+					const isChanged = target[prop] !== value;
+					target[prop] = value;
+
+					if (isChanged) {
+						this.trigger('change', {prop, value});
+					}
+
+					return true;
+				}
+			},
+			proxy = new Proxy(props, handler)
+		;
+
+		__refs.set(this, proxy);
+	}
+
+	get defaults() {
+		return null;
+	}
+
+	get props() {
+		return __refs.get(this);
+	}
+
+}
+
+const __refs$1 = new WeakMap();
+
+
+class Collection extends EventEmitter {
+
+	constructor(models = []) {
+		super();
+
+		const
+			enshureIsModel = (model) =>
+				(model instanceof Model) ? model : new this.Model(model),
+			handler = {
+				get: (target, property) => {
+					const method = target[property];
+
+					if (typeof method === 'function') {
+						return (...args) => {
+							let
+								isChanged = false,
+								result
+							;
+
+							switch (property) {
+								case 'pop':
+								case 'reverse':
+								case 'shift':
+								case 'sort':
+									isChanged = true;
+									break;
+
+								case 'fill':
+									isChanged = true;
+									args[0] = enshureIsModel(args[0]);
+									break;
+
+								case 'push':
+								case 'unshift':
+									isChanged = true;
+									args = args.map(enshureIsModel);
+									break;
+
+								case 'splice':
+									isChanged = true;
+									args = args.map((arg, index) =>
+										(index > 1) ? enshureIsModel(arg) : arg);
+									break;
+							}
+
+							result = method.apply(target, args);
+
+							if (isChanged) {
+								this.trigger('change', {method: property});
+							}
+
+							return result;
+						};
+					}
+
+					return method;
+				}
+			},
+			proxy = new Proxy(models.map(enshureIsModel), handler)
+		;
+
+		__refs$1.set(this, proxy);
+	}
+
+	get Model() {
+		return Model;
+	}
+
+	get models() {
+		return __refs$1.get(this);
+	}
+
+}
+
+export { Collection, Model };
diff --git a/dist/pacto.model.min.js b/dist/pacto.model.min.js
new file mode 100644
index 0000000..c134f36
--- /dev/null
+++ b/dist/pacto.model.min.js
@@ -0,0 +1 @@
+var pacto=function(e,t){"use strict";function r(e,t){if(!(e instanceof t))throw new TypeError("Cannot call a class as a function")}function n(e,t){for(var r=0;r<t.length;r++){var n=t[r];n.enumerable=n.enumerable||!1,n.configurable=!0,"value"in n&&(n.writable=!0),Object.defineProperty(e,n.key,n)}}function o(e,t,r){return t&&n(e.prototype,t),r&&n(e,r),e}function c(e,t,r){return t in e?Object.defineProperty(e,t,{value:r,enumerable:!0,configurable:!0,writable:!0}):e[t]=r,e}function u(e,t){var r=Object.keys(e);if(Object.getOwnPropertySymbols){var n=Object.getOwnPropertySymbols(e);t&&(n=n.filter((function(t){return Object.getOwnPropertyDescriptor(e,t).enumerable}))),r.push.apply(r,n)}return r}function i(e){for(var t=1;t<arguments.length;t++){var r=null!=arguments[t]?arguments[t]:{};t%2?u(Object(r),!0).forEach((function(t){c(e,t,r[t])})):Object.getOwnPropertyDescriptors?Object.defineProperties(e,Object.getOwnPropertyDescriptors(r)):u(Object(r)).forEach((function(t){Object.defineProperty(e,t,Object.getOwnPropertyDescriptor(r,t))}))}return e}function f(e,t){if("function"!=typeof t&&null!==t)throw new TypeError("Super expression must either be null or a function");e.prototype=Object.create(t&&t.prototype,{constructor:{value:e,writable:!0,configurable:!0}}),t&&s(e,t)}function a(e){return(a=Object.setPrototypeOf?Object.getPrototypeOf:function(e){return e.__proto__||Object.getPrototypeOf(e)})(e)}function s(e,t){return(s=Object.setPrototypeOf||function(e,t){return e.__proto__=t,e})(e,t)}function l(){if("undefined"==typeof Reflect||!Reflect.construct)return!1;if(Reflect.construct.sham)return!1;if("function"==typeof Proxy)return!0;try{return Date.prototype.toString.call(Reflect.construct(Date,[],(function(){}))),!0}catch(e){return!1}}function p(e){if(void 0===e)throw new ReferenceError("this hasn't been initialised - super() hasn't been called");return e}function y(e,t){return!t||"object"!=typeof t&&"function"!=typeof t?p(e):t}function b(e){return function(){var t,r=a(e);if(l()){var n=a(this).constructor;t=Reflect.construct(r,arguments,n)}else t=r.apply(this,arguments);return y(this,t)}}var h=new WeakMap,g=function(e){f(n,e);var t=b(n);function n(){var e,o=arguments.length>0&&void 0!==arguments[0]?arguments[0]:{};r(this,n),o=i({},(e=t.call(this)).defaults,{},o);var c={set:function(t,r,n){var o=t[r]!==n;return t[r]=n,o&&e.trigger("change",{prop:r,value:n}),!0}},u=new Proxy(o,c);return h.set(p(e),u),e}return o(n,[{key:"defaults",get:function(){return null}},{key:"props",get:function(){return h.get(this)}}]),n}(t.EventEmitter),v=new WeakMap,O=function(e){f(n,e);var t=b(n);function n(){var e,o=arguments.length>0&&void 0!==arguments[0]?arguments[0]:[];r(this,n),e=t.call(this);var c=function(t){return t instanceof g?t:new e.Model(t)},u={get:function(t,r){var n=t[r];return"function"==typeof n?function(){for(var o=arguments.length,u=new Array(o),i=0;i<o;i++)u[i]=arguments[i];var f,a=!1;switch(r){case"pop":case"reverse":case"shift":case"sort":a=!0;break;case"fill":a=!0,u[0]=c(u[0]);break;case"push":case"unshift":a=!0,u=u.map(c);break;case"splice":a=!0,u=u.map((function(e,t){return t>1?c(e):e}))}return f=n.apply(t,u),a&&e.trigger("change",{method:r}),f}:n}},i=new Proxy(o.map(c),u);return v.set(p(e),i),e}return o(n,[{key:"Model",get:function(){return g}},{key:"models",get:function(){return v.get(this)}}]),n}(t.EventEmitter);return Object.keys(t).forEach((function(r){"default"!==r&&Object.defineProperty(e,r,{enumerable:!0,get:function(){return t[r]}})})),e.Collection=O,e.Model=g,e}({},pacto);