diff --git a/.editorconfig b/.editorconfig
index 8fa3c2a..284dbaf 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -16,3 +16,6 @@ trim_trailing_whitespace = true
 [*.json]
 indent_size = 2
 insert_final_newline = ignore
+
+[*.html]
+insert_final_newline = ignore
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5715cc9..434f997 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,8 +4,30 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
-## [1.0.0] - 2017-12-07
- - First release;
+## [1.1.0] - XXXX-XX-XX
+### Added
+ - Renderers to facilitate integrations of template-engines:
+    - Added `Renderer` interface;
+    - Added `TwigRenderer` that integrates `twig/twig`;
+    - Added fallback template loading support.
+ - Template packs to facilitate customization and extensibility of templates:
+    - Added template pack `default` and defined as fallback;
+    - Added template pack `bootstrap4` that integrates custom elements of Bootstrap v4.0.0-beta.2.
+ - Added extra arg `label` on method `getContext` of `Widget` class;
+ - Support to configure renderer and template pack through `Config` singleton class;
+
+### Changed
+ - Class name `PHPFormConfig` to `Config` and moved to `src/` directory;
+ - `BoundField` attribute name `choices` changed to `options`;
+ - `BoundField` attribute `options` now return an array instead of formated string;
+ - `Widgets`, `labelTag` and `ErrorList` now render through default renderer instead of formatter `fleshgrinder/format`;
+ - `CheckboxSelectMultiple` and `RadioSelect` widget wrapped in an unordered list tag instead of previous `div`;
+ - Method name `getSubWidgets` to `getOptions` in `Widgets` class;
+
+### Removed:
+ - Method `asUL` from `ErrorList` class;
+ - `config.php` and `templates.php` files;
+ - Static method `flatatt` from `Attributes` class;
 
 ## [1.0.1] - 2017-12-07
 ### Added
@@ -14,3 +36,6 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Fixed
  - Fix formatValue method on ChoiceWidget when value is empty or null;
  - Fix validate on ChoiceField when value if empty and not required.
+
+## [1.0.0] - 2017-12-07
+ - First release;
diff --git a/composer.json b/composer.json
index 4e186ca..98f954c 100644
--- a/composer.json
+++ b/composer.json
@@ -15,7 +15,8 @@
   },
   "require": {
     "php": ">=7.0.0",
-    "fleshgrinder/format": "^1.1"
+    "fleshgrinder/format": "^1.1",
+    "twig/twig": "^2.4"
   },
   "require-dev": {
     "phpunit/phpunit": "~6.0",
@@ -38,5 +39,9 @@
       "phpcs --standard=phpcs.xml",
       "phpunit -c phpunit.xml"
     ]
+  },
+  "config": {
+    "sort-packages": true,
+    "optimize-autoloader": true
   }
 }
diff --git a/config.php b/config.php
index a44dd7c..1e7d929 100644
--- a/config.php
+++ b/config.php
@@ -4,7 +4,6 @@
 class PHPFormConfig
 {
     const MESSAGES_FILE_PATH = 'src/messages.php';
-    const TEMPLATES_FILE_PATH = 'src/templates.php';
 
     private static $config = null;
 
@@ -14,7 +13,6 @@ class PHPFormConfig
     private function __construct()
     {
         $this->messages = include static::MESSAGES_FILE_PATH;
-        $this->templates = include static::TEMPLATES_FILE_PATH;
     }
 
     public static function getInstance()
diff --git a/src/Config.php b/src/Config.php
new file mode 100644
index 0000000..ab7c2d2
--- /dev/null
+++ b/src/Config.php
@@ -0,0 +1,75 @@
+<?php
+namespace PHPForm;
+
+use PHPForm\Renderers\TwigRenderer;
+
+class Config extends Singleton
+{
+    /**
+     * @var string Directory with templates
+     */
+    protected $templates_dir = __DIR__ . '/templates/';
+
+    /**
+     * @var string Default fallback template pack
+     */
+    protected $fallback_template_pack = "default";
+
+    /**
+     * @var string Default template pack defined. If null, fallback is used.
+     */
+    protected $template_pack = null;
+
+    /**
+     * @var string Renderer class used to render html content
+     */
+    protected $renderer_class = TwigRenderer::class;
+
+    /**
+     * @var PHPForm\Renderers\Renderer Renderer instance based on $renderer_class.
+     */
+    private $renderer;
+
+    /**
+     * Templates path accordingly with defined template pack.
+     *
+     * @return string
+     */
+    private function buildPath($template_pack)
+    {
+        $path = $this->templates_dir . $template_pack . "/";
+
+        if (!file_exists($path)) {
+            trigger_error("Template pack dir '$path' don't exists.", E_USER_ERROR);
+        }
+
+        return $path;
+    }
+
+    /**
+     * Return renderer class instantiated
+     *
+     * @return PHPForm\Renderers\Renderer
+     */
+    public function getRenderer()
+    {
+        if (is_null($this->renderer)) {
+            $fallback_pack_dir = $this->buildPath($this->fallback_template_pack);
+            $pack_dir = !is_null($this->template_pack) ? $this->buildPath($this->template_pack) : null;
+
+            $this->renderer = new $this->renderer_class($fallback_pack_dir, $pack_dir);
+        }
+
+        return $this->renderer;
+    }
+
+    /**
+     * Define template pack
+     *
+     * @param string
+     */
+    public function setTemplatePack($template_pack)
+    {
+        $this->template_pack = $template_pack;
+    }
+}
diff --git a/src/Errors/ErrorList.php b/src/Errors/ErrorList.php
index 1d2c2b2..75d0a25 100644
--- a/src/Errors/ErrorList.php
+++ b/src/Errors/ErrorList.php
@@ -3,42 +3,27 @@
 
 use ArrayObject;
 
-use Fleshgrinder\Core\Formatter;
-
-use PHPForm\PHPFormConfig;
+use PHPForm\Config;
 
 class ErrorList extends ArrayObject
 {
+    const TEMPLATE = "error_list.html";
+
     /**
      * Returns the error list rendered as HTML.
      *
      * @return string
      */
     public function __toString()
-    {
-        return $this->asUL();
-    }
-
-    /**
-     * Returns an error dictionary as an unordered list in HTML.
-     *
-     * @return string
-     */
-    public function asUL()
     {
         if (!count($this)) {
             return '';
         }
 
-        $items = [];
-        $list_item_template = PHPFormConfig::getITemplate("ERRORLIST_ITEM");
-
-        foreach ($this as $error) {
-            $items[] = Formatter::format($list_item_template, array("content" => $error));
-        }
-
-        $list_template = PHPFormConfig::getITemplate("ERRORLIST");
+        $renderer = Config::getInstance()->getRenderer();
 
-        return Formatter::format($list_template, array("items" => implode($items)));
+        return $renderer->render(self::TEMPLATE, array(
+            "errors" => $this,
+        ));
     }
 }
diff --git a/src/Fields/BoundField.php b/src/Fields/BoundField.php
index 60544f2..887c59d 100644
--- a/src/Fields/BoundField.php
+++ b/src/Fields/BoundField.php
@@ -1,17 +1,16 @@
 <?php
 namespace PHPForm\Fields;
 
-use Fleshgrinder\Core\Formatter;
-
-use PHPForm\PHPFormConfig;
-use PHPForm\Utils\Attributes;
+use PHPForm\Config;
 
 class BoundField
 {
+    const TEMPLATE_LABEL = "label.html";
+
     private $form;
     private $field;
     private $name;
-    private $subwidgets_cache;
+    private $options_cache;
 
     public $html_name;
     public $help_text;
@@ -55,22 +54,21 @@ public function __get($name)
             return $this->getValue();
         }
 
-        if ($name == 'choices') {
-            if (!isset($subwidgets_cache)) {
-                $subwidgets_cache = $this->getSubWidgets();
+        if ($name == 'options') {
+            if (!isset($options_cache)) {
+                $options_cache = $this->getOptions();
             }
-            return $subwidgets_cache;
+            return $options_cache;
         }
 
-        return parent::__get($name);
+        return null;
     }
 
-    private function getSubWidgets(array $attrs = array())
+    private function getOptions(array $attrs = array())
     {
-        $widget = $this->field->getWidget();
         $attrs = $this->buildWidgetAttrs($attrs);
 
-        return $widget->getSubWidgets($this->html_name, $this->getValue(), $attrs);
+        return $this->field->getWidget()->getOptions($this->html_name, $this->getValue(), $attrs);
     }
 
     protected function asWidget($widget = null, array $attrs = array())
@@ -79,10 +77,10 @@ protected function asWidget($widget = null, array $attrs = array())
 
         $attrs = $this->buildWidgetAttrs($attrs);
 
-        return $widget->render($this->html_name, $this->getValue(), $attrs);
+        return $widget->render($this->html_name, $this->getValue(), $this->label, $attrs);
     }
 
-    public function labelTag($contents = null, array $attrs = null)
+    public function labelTag($contents = null, array $attrs = array())
     {
         $contents = is_null($contents) ? $this->label : $contents;
 
@@ -90,20 +88,15 @@ public function labelTag($contents = null, array $attrs = null)
             return "";
         }
 
-        if (!is_null($attrs)) {
-            $attrs = Attributes::flatatt($attrs);
-        }
-
         $widget = $this->field->getWidget();
 
-        $label_tpl = PHPFormConfig::getITemplate("LABEL");
-        $label_required_tpl = PHPFormConfig::getITemplate("LABEL_REQUIRED");
+        $renderer = Config::getInstance()->getRenderer();
 
-        return Formatter::format($label_tpl, array(
+        return $renderer->render(self::TEMPLATE_LABEL, array(
             "for" => $widget->buildAutoId($this->html_name),
             "attrs" => $attrs,
             "contents" => $contents,
-            "required" => $this->field->isRequired() ? $label_required_tpl : null
+            "required" => $this->field->isRequired()
         ));
     }
 
diff --git a/src/Fields/MultipleChoiceField.php b/src/Fields/MultipleChoiceField.php
index b3d8f12..746987c 100644
--- a/src/Fields/MultipleChoiceField.php
+++ b/src/Fields/MultipleChoiceField.php
@@ -4,8 +4,6 @@
  */
 namespace PHPForm\Fields;
 
-use Fleshgrinder\Core\Formatter;
-
 use PHPForm\Exceptions\ValidationError;
 use PHPForm\PHPFormConfig;
 use PHPForm\Widgets\SelectMultiple;
diff --git a/src/Forms/Form.php b/src/Forms/Form.php
index 94b24ac..4fb5ae5 100644
--- a/src/Forms/Form.php
+++ b/src/Forms/Form.php
@@ -16,7 +16,7 @@
 
 abstract class Form implements ArrayAccess, Iterator, Countable
 {
-    const PREFIX_TEMPLATE = '{prefix}-{field_name}';
+    const PREFIX_FORMAT = '%s-%s';
     const NON_FIELD_ERRORS = '__all__';
 
     /**
@@ -145,10 +145,7 @@ public function __get(string $name)
     public function addPrefix(string $field_name)
     {
         if (!is_null($this->prefix)) {
-            return Formatter::format(self::PREFIX_TEMPLATE, array(
-                "prefix" => $this->prefix,
-                "field_name" => $field_name
-            ));
+            return sprintf(static::PREFIX_FORMAT, $this->prefix, $field_name);
         }
 
         return $field_name;
diff --git a/src/Renderers/Renderer.php b/src/Renderers/Renderer.php
new file mode 100644
index 0000000..ed4a1ca
--- /dev/null
+++ b/src/Renderers/Renderer.php
@@ -0,0 +1,12 @@
+<?php
+/**
+* Abstract class for renderers definition
+*/
+namespace PHPForm\Renderers;
+
+interface Renderer
+{
+    public function __construct(string $fallback_templates_dir, string $templates_dir);
+    public function getTemplate(string $template_name);
+    public function render(string $template_name, array $context);
+}
diff --git a/src/Renderers/TwigRenderer.php b/src/Renderers/TwigRenderer.php
new file mode 100644
index 0000000..5defe26
--- /dev/null
+++ b/src/Renderers/TwigRenderer.php
@@ -0,0 +1,38 @@
+<?php
+/**
+*
+*/
+namespace PHPForm\Renderers;
+
+use Twig_Loader_Filesystem;
+use Twig_Environment;
+use Twig_Loader_Chain;
+
+class TwigRenderer implements Renderer
+{
+    private $twig;
+
+    public function __construct(string $fallback_templates_dir, string $templates_dir = null)
+    {
+        $loaders = new Twig_Loader_Chain();
+
+        if (!is_null($templates_dir)) {
+            $loaders->addLoader(new Twig_Loader_Filesystem($templates_dir));
+        }
+
+        $loaders->addLoader(new Twig_Loader_Filesystem($fallback_templates_dir));
+
+        $this->twig = new Twig_Environment($loaders);
+    }
+
+    public function getTemplate(string $template_name)
+    {
+        return $this->twig->load($template_name);
+    }
+
+    public function render(string $template_name, array $context)
+    {
+        $template = $this->getTemplate($template_name);
+        return $template->render($context);
+    }
+}
diff --git a/src/Singleton.php b/src/Singleton.php
new file mode 100644
index 0000000..a0e51a8
--- /dev/null
+++ b/src/Singleton.php
@@ -0,0 +1,38 @@
+<?php
+namespace PHPForm;
+
+abstract class Singleton
+{
+    /**
+     * Returns a unique instance of a class.
+     * @return Singleton The unique instance.
+     */
+    public static function getInstance()
+    {
+        static $instance = null;
+        if (null === $instance) {
+            $instance = new static();
+        }
+        return $instance;
+    }
+    /**
+     * Constructor of the protected type prevents a new instance of the Class
+     * from being created through the `new` operator outside that class.
+     */
+    protected function __construct()
+    {
+    }
+    /**
+     * Clone method of the private type prevents the cloning of this instance
+     */
+    private function __clone()
+    {
+    }
+    /**
+     * Unserialize method of the private type to prevent the deserialization of
+     * the instance
+     */
+    private function __wakeup()
+    {
+    }
+}
diff --git a/src/Utils/Attributes.php b/src/Utils/Attributes.php
index 8529012..cedf360 100644
--- a/src/Utils/Attributes.php
+++ b/src/Utils/Attributes.php
@@ -4,28 +4,8 @@
  */
 namespace PHPForm\Utils;
 
-use Fleshgrinder\Core\Formatter;
-
 class Attributes
 {
-    public static function flatatt($attrs)
-    {
-        if (!is_array($attrs)) {
-            return '';
-        }
-
-        $flat = [];
-
-        foreach ($attrs as $name => $value) {
-            $flat[] = Formatter::format('{name}="{value}"', array(
-                "name" => $name,
-                "value" => htmlentities($value)
-            ));
-        }
-
-        return implode(" ", $flat);
-    }
-
     public static function prettyName($name)
     {
         return ucfirst(str_replace("_", " ", $name));
diff --git a/src/Widgets/CheckboxInput.php b/src/Widgets/CheckboxInput.php
index 0f63c0e..37e2f24 100644
--- a/src/Widgets/CheckboxInput.php
+++ b/src/Widgets/CheckboxInput.php
@@ -6,16 +6,17 @@
 
 class CheckboxInput extends Input
 {
-    protected $input_type = 'checkbox';
+    const TEMPLATE = 'checkbox.html';
+    const INPUT_TYPE = 'checkbox';
 
-    public function getContext(string $name, $value, array $attrs = null)
+    public function getContext(string $name, $value, string $label = null, array $attrs = null)
     {
         if ($value) {
             $attrs = is_null($attrs) ? array() : $attrs;
             $attrs["checked"] = "checked";
         }
 
-        return parent::getContext($name, $value, $attrs);
+        return parent::getContext($name, $value, $label, $attrs);
     }
 
     public function valueFromData($data, $files, string $name)
diff --git a/src/Widgets/CheckboxSelectMultiple.php b/src/Widgets/CheckboxSelectMultiple.php
index d6a220a..ab6ebad 100644
--- a/src/Widgets/CheckboxSelectMultiple.php
+++ b/src/Widgets/CheckboxSelectMultiple.php
@@ -8,22 +8,11 @@
 
 class CheckboxSelectMultiple extends ChoiceWidget
 {
+    const TEMPLATE = 'checkbox_select.html';
+    const TEMPLATE_CHOICE = 'checkbox_select_option.html';
+    const INPUT_TYPE = 'checkbox';
+
     protected $allow_multiple_selected = true;
     protected $option_inherits_attrs = true;
-    protected $selected_attribute = "checked";
-    protected $input_type = "checkbox";
-
-    /**
-     * The constructor.
-     */
-    public function __construct(array $choices = array(), array $attrs = null)
-    {
-        $this->template = PHPFormConfig::getITemplate("CHECKBOX_SELECT_MULTIPLE");
-        $this->template_choice = sprintf(
-            PHPFormConfig::getITemplate("CHECKBOX_SELECT_MULTIPLE_ITEM"),
-            PHPFormConfig::getITemplate("INPUT")
-        );
-
-        parent::__construct($choices, $attrs);
-    }
+    protected $selected_attribute = 'checked';
 }
diff --git a/src/Widgets/ChoiceWidget.php b/src/Widgets/ChoiceWidget.php
index a9fe9fa..7e8d8ca 100644
--- a/src/Widgets/ChoiceWidget.php
+++ b/src/Widgets/ChoiceWidget.php
@@ -4,17 +4,35 @@
  */
 namespace PHPForm\Widgets;
 
-use Fleshgrinder\Core\Formatter;
-
 use PHPForm\Utils\Attributes;
 
 abstract class ChoiceWidget extends Widget
 {
-    protected $template_choice = "";
+    const TEMPLATE_CHOICE = '';
+    const INPUT_TYPE = null;
+
+    /**
+     * Allow multiple choices being selected.
+     * @var boolean
+     */
     protected $allow_multiple_selected = false;
-    protected $input_type = null;
+
+    /**
+     * Option inherit the attrs of mains widget.
+     * @var boolean
+     */
     protected $option_inherits_attrs = true;
+
+    /**
+     * Attr name when option is selected.
+     * @var string
+     */
     protected $selected_attribute = "selected";
+
+    /**
+     * Valid choices for this widget.
+     * @var array
+     */
     protected $choices;
 
     /**
@@ -27,31 +45,54 @@ public function __construct(array $choices = array(), array $attrs = null)
         $this->setChoices($choices);
     }
 
+    /**
+     * @param array $choices Choices to be setted.
+     */
     public function setChoices(array $choices)
     {
         $this->choices = $choices;
     }
 
-    public function buildName($name)
+    /**
+     * If allow multiple selected, add [] to the end of name.
+     *
+     * @param  string $name
+     * @return string
+     */
+    protected function buildName(string $name)
     {
-        if ($this->allow_multiple_selected && substr($name, -2, 2) !== "[]") {
-            $name = $name . "[]";
-        }
-
-        return $name;
+        return $this->allow_multiple_selected ? $name . "[]" : $name;
     }
 
-    public function getContext(string $name, $value, array $attrs = null)
+    /**
+     * Prepare context to be used on render method.
+     *
+     * @param string $name  Field name.
+     * @param mixed  $value Field value.
+     * @param array  $attrs Extra widget attributes.
+     *
+     * @return array
+     */
+    protected function getContext(string $name, $value, string $label = null, array $attrs = null)
     {
-        $context = parent::getContext($name, $value, $attrs);
+        $context = parent::getContext($name, $value, $label, $attrs);
 
         $context["name"] = $this->buildName($name);
-        $context["options"] = implode($this->getSubWidgets($name, $value, $attrs));
+        $context["options"] = $this->getOptions($name, $value, $attrs);
 
         return $context;
     }
 
-    public function getSubWidgets(string $name, $value, array $attrs = null)
+    /**
+     * Prepare options.
+     *
+     * @param string $name  Choice name.
+     * @param mixed  $value Choice value.
+     * @param array  $attrs Extra choice attributes.
+     *
+     * @return array
+     */
+    public function getOptions(string $name, $value, array $attrs = null)
     {
         $value = $this->formatValue($value);
         $subwidgets = array();
@@ -63,21 +104,33 @@ public function getSubWidgets(string $name, $value, array $attrs = null)
             $selected = false;
 
             if (!$has_selected || $this->allow_multiple_selected) {
-                $selected = in_array($choice_value, $value);
-                $has_selected = $selected;
+                $has_selected = $selected = in_array($choice_value, $value);
             }
 
-            $context = $this->getSubWidgetContext($name, $choice_value, $choice_label, $selected, $index, $attrs);
-
-            $subwidgets[] = Formatter::format($this->template_choice, $context);
-
-            $index++;
+            $subwidgets[] = $this->buildOption(
+                $name,
+                $choice_value,
+                $choice_label,
+                $selected,
+                $index++,
+                $attrs
+            );
         }
 
         return $subwidgets;
     }
 
-    public function getSubWidgetContext(
+    /**
+     * @param  string     $name
+     * @param  mixed      $value
+     * @param  string     $label
+     * @param  bool       $is_selected
+     * @param  int        $index
+     * @param  array|null $attrs
+     *
+     * @return array
+     */
+    protected function buildOption(
         string $name,
         $value,
         string $label,
@@ -99,14 +152,22 @@ public function getSubWidgetContext(
 
         return array(
             "for" => $this->buildAutoId($name, $index),
-            "type" => $this->input_type,
-            "name" => htmlentities($this->buildName($name)),
-            "value" => htmlentities($value),
-            "label" => htmlentities($label),
-            "attrs" => Attributes::flatatt($attrs),
+            "type" => static::INPUT_TYPE,
+            "name" => $this->buildName($name),
+            "value" => $value,
+            "label" => $label,
+            "attrs" => $attrs,
+            "template" => static::TEMPLATE_CHOICE,
         );
     }
 
+    /**
+     * Format value to be rendered in html.
+     *
+     * @param mixed $value Value to be formated.
+     *
+     * @return array
+     */
     protected function formatValue($value)
     {
         if (is_array($value)) {
diff --git a/src/Widgets/DateInput.php b/src/Widgets/DateInput.php
index 2e7eb39..be81450 100644
--- a/src/Widgets/DateInput.php
+++ b/src/Widgets/DateInput.php
@@ -6,8 +6,5 @@
 
 class DateInput extends TemporalInput
 {
-    /**
-    * @var string Format of temporal value.
-    */
     const FORMAT = 'd-m-Y';
 }
diff --git a/src/Widgets/EmailInput.php b/src/Widgets/EmailInput.php
index 7170af0..3e1e6b3 100644
--- a/src/Widgets/EmailInput.php
+++ b/src/Widgets/EmailInput.php
@@ -6,5 +6,6 @@
 
 class EmailInput extends Input
 {
-    protected $input_type = 'email';
+    const TEMPLATE = 'email.html';
+    const INPUT_TYPE = 'email';
 }
diff --git a/src/Widgets/FileInput.php b/src/Widgets/FileInput.php
index a7f6f37..8ed0ec9 100644
--- a/src/Widgets/FileInput.php
+++ b/src/Widgets/FileInput.php
@@ -6,7 +6,8 @@
 
 class FileInput extends Input
 {
-    protected $input_type = 'file';
+    const TEMPLATE = 'file.html';
+    const INPUT_TYPE = 'file';
 
     /**
      * FileInput don't render the value.
diff --git a/src/Widgets/HiddenInput.php b/src/Widgets/HiddenInput.php
index b06c857..c5811fb 100644
--- a/src/Widgets/HiddenInput.php
+++ b/src/Widgets/HiddenInput.php
@@ -6,5 +6,6 @@
 
 class HiddenInput extends Input
 {
-    protected $input_type = 'hidden';
+    const TEMPLATE = 'hidden.html';
+    const INPUT_TYPE = 'hidden';
 }
diff --git a/src/Widgets/Input.php b/src/Widgets/Input.php
index 4454d72..3f4add3 100644
--- a/src/Widgets/Input.php
+++ b/src/Widgets/Input.php
@@ -4,24 +4,10 @@
  */
 namespace PHPForm\Widgets;
 
-use PHPForm\PHPFormConfig;
-
 abstract class Input extends Widget
 {
-    /**
-    * @var string The input type to use for the widget.
-    */
-    protected $input_type = null;
-
-    /**
-     * The constructor.
-     */
-    public function __construct(array $attrs = null)
-    {
-        $this->template = PHPFormConfig::getITemplate("INPUT");
-
-        parent::__construct($attrs);
-    }
+    const TEMPLATE = 'input.html';
+    const INPUT_TYPE = null;
 
     /**
      * Prepare context to be used on render method.
@@ -32,10 +18,12 @@ public function __construct(array $attrs = null)
      *
      * @return array
      */
-    public function getContext(string $name, $value, array $attrs = null)
+    public function getContext(string $name, $value, string $label = null, array $attrs = null)
     {
-        $context = parent::getContext($name, $value, $attrs);
-        $context["type"] = $this->input_type;
+        $context = parent::getContext($name, $value, $label, $attrs);
+
+        $context["type"] = static::INPUT_TYPE;
+
         return $context;
     }
 }
diff --git a/src/Widgets/NumberInput.php b/src/Widgets/NumberInput.php
index 471f90d..3a57046 100644
--- a/src/Widgets/NumberInput.php
+++ b/src/Widgets/NumberInput.php
@@ -6,5 +6,6 @@
 
 class NumberInput extends Input
 {
-    protected $input_type = 'number';
+    const TEMPLATE = 'number.html';
+    const INPUT_TYPE = 'number';
 }
diff --git a/src/Widgets/PasswordInput.php b/src/Widgets/PasswordInput.php
index a344cc1..831a34b 100644
--- a/src/Widgets/PasswordInput.php
+++ b/src/Widgets/PasswordInput.php
@@ -6,7 +6,8 @@
 
 class PasswordInput extends Input
 {
-    protected $input_type = 'password';
+    const TEMPLATE = 'password.html';
+    const INPUT_TYPE = 'password';
 
     /**
      * PasswordInput don't render the value.
diff --git a/src/Widgets/RadioSelect.php b/src/Widgets/RadioSelect.php
index 74575db..dd28e60 100644
--- a/src/Widgets/RadioSelect.php
+++ b/src/Widgets/RadioSelect.php
@@ -8,21 +8,10 @@
 
 class RadioSelect extends ChoiceWidget
 {
-    protected $option_inherits_attrs = true;
-    protected $selected_attribute = "checked";
-    protected $input_type = "radio";
-
-    /**
-     * The constructor.
-     */
-    public function __construct(array $choices = array(), array $attrs = null)
-    {
-        $this->template = PHPFormConfig::getITemplate("RADIOSELECT");
-        $this->template_choice = sprintf(
-            PHPFormConfig::getITemplate("RADIOSELECT_ITEM"),
-            PHPFormConfig::getITemplate("INPUT")
-        );
+    const TEMPLATE = 'radio_select.html';
+    const TEMPLATE_CHOICE = 'radio_select_option.html';
+    const INPUT_TYPE = 'radio';
 
-        parent::__construct($choices, $attrs);
-    }
+    protected $option_inherits_attrs = true;
+    protected $selected_attribute = 'checked';
 }
diff --git a/src/Widgets/Select.php b/src/Widgets/Select.php
index 728a8f3..93dc67a 100644
--- a/src/Widgets/Select.php
+++ b/src/Widgets/Select.php
@@ -8,29 +8,19 @@
 
 class Select extends ChoiceWidget
 {
-    protected $option_inherits_attrs = false;
-
-    /**
-     * The constructor.
-     */
-    public function __construct(array $choices = array(), array $attrs = null)
-    {
-        $this->template = PHPFormConfig::getITemplate("SELECT");
-        $this->template_choice = PHPFormConfig::getITemplate("SELECT_ITEM");
+    const TEMPLATE = 'select.html';
+    const TEMPLATE_CHOICE = 'select_option.html';
 
-        parent::__construct($choices, $attrs);
-    }
+    protected $option_inherits_attrs = false;
 
-    public function getContext(string $name, $value, array $attrs = null)
+    public function getContext(string $name, $value, string $label = null, array $attrs = null)
     {
-        if (is_null($attrs)) {
-            $attrs = array();
-        }
+        $context = parent::getContext($name, $value, $label, $attrs);
 
         if ($this->allow_multiple_selected) {
-            $attrs["multiple"] = "multiple";
+            $context["attrs"]["multiple"] = "multiple";
         }
 
-        return parent::getContext($name, $value, $attrs);
+        return $context;
     }
 }
diff --git a/src/Widgets/TextInput.php b/src/Widgets/TextInput.php
index 71d28d5..5d8f1a6 100644
--- a/src/Widgets/TextInput.php
+++ b/src/Widgets/TextInput.php
@@ -6,5 +6,6 @@
 
 class TextInput extends Input
 {
-    protected $input_type = 'text';
+    const TEMPLATE = 'text.html';
+    const INPUT_TYPE = 'text';
 }
diff --git a/src/Widgets/Textarea.php b/src/Widgets/Textarea.php
index 41e4dc8..861a23d 100644
--- a/src/Widgets/Textarea.php
+++ b/src/Widgets/Textarea.php
@@ -4,10 +4,11 @@
  */
 namespace PHPForm\Widgets;
 
-use PHPForm\PHPFormConfig;
-
 class Textarea extends Widget
 {
+    const TEMPLATE = 'textarea.html';
+    const INPUT_TYPE = 'textarea';
+
     /**
      * The constructor.
      */
@@ -19,8 +20,6 @@ public function __construct(array $attrs = null)
             $extra_attrs = array_merge($extra_attrs, $attrs);
         }
 
-        $this->template = PHPFormConfig::getITemplate("TEXTAREA");
-
         parent::__construct($extra_attrs);
     }
 }
diff --git a/src/Widgets/URLInput.php b/src/Widgets/URLInput.php
index a4c2bcd..2cd6c6a 100644
--- a/src/Widgets/URLInput.php
+++ b/src/Widgets/URLInput.php
@@ -6,5 +6,6 @@
 
 class URLInput extends Input
 {
-    protected $input_type = 'url';
+    const TEMPLATE = 'url.html';
+    const INPUT_TYPE = 'url';
 }
diff --git a/src/Widgets/Widget.php b/src/Widgets/Widget.php
index 81e78a5..6c52b4a 100644
--- a/src/Widgets/Widget.php
+++ b/src/Widgets/Widget.php
@@ -4,15 +4,11 @@
  */
 namespace PHPForm\Widgets;
 
-use Fleshgrinder\Core\Formatter;
-
-use PHPForm\Utils\Attributes;
+use PHPForm\Config;
 
 abstract class Widget
 {
-    const AUTO_ID_TEMPLATE = "id_{name}[_{index}?]";
-
-    protected $template = "";
+    const TEMPLATE = "";
 
     /**
     * @var array Attributes to be added to the widget.
@@ -39,11 +35,13 @@ public function __construct(array $attrs = null)
      *
      * @return string
      */
-    public function render(string $name, $value, array $attrs = null)
+    public function render(string $name, $value, string $label = null, array $attrs = null)
     {
-        $context = $this->getContext($name, $value, $attrs);
+        $renderer = Config::getInstance()->getRenderer();
+
+        $context = $this->getContext($name, $value, $label, $attrs);
 
-        return Formatter::format($this->template, $context);
+        return $renderer->render(static::TEMPLATE, $context);
     }
 
     /**
@@ -55,7 +53,7 @@ public function render(string $name, $value, array $attrs = null)
      *
      * @return array
      */
-    protected function getContext(string $name, $value, array $attrs = null)
+    protected function getContext(string $name, $value, string $label = null, array $attrs = null)
     {
         $value = $this->formatValue($value);
         $attrs = $this->buildAttrs($attrs);
@@ -65,9 +63,11 @@ protected function getContext(string $name, $value, array $attrs = null)
         }
 
         return array(
-            "name" => htmlentities($name),
-            "attrs" => Attributes::flatatt($attrs),
-            "value" => is_string($value) ? htmlspecialchars($value) : $value,
+            "for" => $this->buildAutoId($name),
+            "name" => $name,
+            "attrs" => $attrs,
+            "value" => $value,
+            "label" => $label,
         );
     }
 
@@ -98,13 +98,13 @@ public function valueFromData($data, $files, string $name)
     }
 
     /**
-    * Return defined subwidget.
+    * Return defined options.
     *
     * @return array
     */
-    public function getSubWidgets(string $name, $value, array $attrs = null)
+    public function getOptions(string $name, $value, array $attrs = null)
     {
-        return $this->widget;
+        return array();
     }
 
     /**
@@ -144,9 +144,7 @@ private function buildAttrs(array $extra_attrs = null)
      */
     public function buildAutoId(string $name, int $index = null)
     {
-        return Formatter::format(self::AUTO_ID_TEMPLATE, array(
-            "name" => $name,
-            "index" => $index
-        ));
+        $auto_id = is_null($index) ? "id_%s" : "id_%s_%s";
+        return sprintf($auto_id, $name, $index);
     }
 }
diff --git a/src/templates.php b/src/templates.php
deleted file mode 100644
index 75fc3b7..0000000
--- a/src/templates.php
+++ /dev/null
@@ -1,23 +0,0 @@
-<?php
-
-return array(
-    "LABEL" => '<label for="{for}"[ {attrs}?]>{contents}[ {required}?]</label>',
-    "LABEL_REQUIRED" => '<span class="required">*</span>',
-
-    // ErrorList
-    "ERRORLIST" => '<ul class="errorlist">{items}</ul>',
-    "ERRORLIST_ITEM" => '<li>{content}</li>',
-
-    // Widgets
-    "TEXTAREA" => '<textarea name="{name}" [{attrs}?]>[{value}?]</textarea>',
-    "INPUT" => '<input type="{type}" name="{name}" [{attrs}?] [value="{value}?"]/>',
-
-    "SELECT" => '<select name="{name}"[ {attrs}?]>{options}</select>',
-    "SELECT_ITEM" => '<option value="{value}"[ {attrs}?]>{label}</option>',
-
-    "CHECKBOX_SELECT_MULTIPLE" => '<div>{options}</div>',
-    "CHECKBOX_SELECT_MULTIPLE_ITEM" => '<label for="{for}">%s {label}</label>',
-
-    "RADIOSELECT" => '<div>{options}</div>',
-    "RADIOSELECT_ITEM" => '<label for="{for}">%s {label}</label>',
-);
diff --git a/src/templates/bootstrap4/checkbox.html b/src/templates/bootstrap4/checkbox.html
new file mode 100644
index 0000000..13a48ac
--- /dev/null
+++ b/src/templates/bootstrap4/checkbox.html
@@ -0,0 +1 @@
+{% include 'multiple_input_option.html' %}
\ No newline at end of file
diff --git a/src/templates/bootstrap4/file.html b/src/templates/bootstrap4/file.html
new file mode 100644
index 0000000..6969e76
--- /dev/null
+++ b/src/templates/bootstrap4/file.html
@@ -0,0 +1,5 @@
+<label class="custom-file">
+    {% set attrs = attrs|merge({'class': 'custom-file-input'}) %}
+    {% include 'input.html' %}
+    <span class="custom-file-control"></span>
+</label>
\ No newline at end of file
diff --git a/src/templates/bootstrap4/multiple_input.html b/src/templates/bootstrap4/multiple_input.html
new file mode 100644
index 0000000..933b66f
--- /dev/null
+++ b/src/templates/bootstrap4/multiple_input.html
@@ -0,0 +1,5 @@
+<div id="{{attrs.id}}" class="custom-controls-stacked">
+    {% for option in options %}
+        {% include option.template with option only %}
+    {% endfor %}
+</div>
\ No newline at end of file
diff --git a/src/templates/bootstrap4/multiple_input_option.html b/src/templates/bootstrap4/multiple_input_option.html
new file mode 100644
index 0000000..1fe14fc
--- /dev/null
+++ b/src/templates/bootstrap4/multiple_input_option.html
@@ -0,0 +1,6 @@
+<label for="{{for|e}}" class="custom-control custom-{{ type|e }}">
+    {% set attrs = attrs|merge({'class': 'custom-control-input'}) %}
+    {% include 'input.html' %}
+    <span class="custom-control-indicator"></span>
+    <span class="custom-control-description">{{ label|e }}</span>
+</label>
\ No newline at end of file
diff --git a/src/templates/default/attrs.html b/src/templates/default/attrs.html
new file mode 100644
index 0000000..878ba67
--- /dev/null
+++ b/src/templates/default/attrs.html
@@ -0,0 +1 @@
+{% for name, value in attrs %} {{ name }}="{{ value|e }}"{% endfor %}
\ No newline at end of file
diff --git a/src/templates/default/checkbox.html b/src/templates/default/checkbox.html
new file mode 100644
index 0000000..3c0c8a9
--- /dev/null
+++ b/src/templates/default/checkbox.html
@@ -0,0 +1 @@
+{% include 'input.html' %}
\ No newline at end of file
diff --git a/src/templates/default/checkbox_select.html b/src/templates/default/checkbox_select.html
new file mode 100644
index 0000000..86f1a99
--- /dev/null
+++ b/src/templates/default/checkbox_select.html
@@ -0,0 +1 @@
+{% include 'multiple_input.html' %}
\ No newline at end of file
diff --git a/src/templates/default/checkbox_select_option.html b/src/templates/default/checkbox_select_option.html
new file mode 100644
index 0000000..13a48ac
--- /dev/null
+++ b/src/templates/default/checkbox_select_option.html
@@ -0,0 +1 @@
+{% include 'multiple_input_option.html' %}
\ No newline at end of file
diff --git a/src/templates/default/email.html b/src/templates/default/email.html
new file mode 100644
index 0000000..3c0c8a9
--- /dev/null
+++ b/src/templates/default/email.html
@@ -0,0 +1 @@
+{% include 'input.html' %}
\ No newline at end of file
diff --git a/src/templates/default/error_list.html b/src/templates/default/error_list.html
new file mode 100644
index 0000000..5622853
--- /dev/null
+++ b/src/templates/default/error_list.html
@@ -0,0 +1 @@
+<ul class="errorlist">{% for error in errors %}<li>{{error|e}}</li>{% endfor %}</ul>
\ No newline at end of file
diff --git a/src/templates/default/file.html b/src/templates/default/file.html
new file mode 100644
index 0000000..3c0c8a9
--- /dev/null
+++ b/src/templates/default/file.html
@@ -0,0 +1 @@
+{% include 'input.html' %}
\ No newline at end of file
diff --git a/src/templates/default/hidden.html b/src/templates/default/hidden.html
new file mode 100644
index 0000000..3c0c8a9
--- /dev/null
+++ b/src/templates/default/hidden.html
@@ -0,0 +1 @@
+{% include 'input.html' %}
\ No newline at end of file
diff --git a/src/templates/default/input.html b/src/templates/default/input.html
new file mode 100644
index 0000000..32e3036
--- /dev/null
+++ b/src/templates/default/input.html
@@ -0,0 +1 @@
+<input type="{{type|e}}" name="{{name|e}}"{% if value is not empty %} value="{{value|e}}"{% endif %}{% include 'attrs.html' with attrs %}/>
\ No newline at end of file
diff --git a/src/templates/default/label.html b/src/templates/default/label.html
new file mode 100644
index 0000000..2ac0f4f
--- /dev/null
+++ b/src/templates/default/label.html
@@ -0,0 +1 @@
+<label for="{{for|e}}"{% include 'attrs.html' with attrs %}>{{contents|e}}{% if required %} <span class="required">*</span>{% endif %}</label>
\ No newline at end of file
diff --git a/src/templates/default/multiple_input.html b/src/templates/default/multiple_input.html
new file mode 100644
index 0000000..fa8174e
--- /dev/null
+++ b/src/templates/default/multiple_input.html
@@ -0,0 +1,5 @@
+<ul id="{{attrs.id}}">
+    {% for option in options %}
+        <li>{% include option.template with option only %}</li>
+    {% endfor %}
+</ul>
\ No newline at end of file
diff --git a/src/templates/default/multiple_input_option.html b/src/templates/default/multiple_input_option.html
new file mode 100644
index 0000000..26d96b6
--- /dev/null
+++ b/src/templates/default/multiple_input_option.html
@@ -0,0 +1 @@
+<label for="{{for|e}}">{% include 'input.html' %} {{label|e}}</label>
\ No newline at end of file
diff --git a/src/templates/default/number.html b/src/templates/default/number.html
new file mode 100644
index 0000000..3c0c8a9
--- /dev/null
+++ b/src/templates/default/number.html
@@ -0,0 +1 @@
+{% include 'input.html' %}
\ No newline at end of file
diff --git a/src/templates/default/password.html b/src/templates/default/password.html
new file mode 100644
index 0000000..3c0c8a9
--- /dev/null
+++ b/src/templates/default/password.html
@@ -0,0 +1 @@
+{% include 'input.html' %}
\ No newline at end of file
diff --git a/src/templates/default/radio_select.html b/src/templates/default/radio_select.html
new file mode 100644
index 0000000..86f1a99
--- /dev/null
+++ b/src/templates/default/radio_select.html
@@ -0,0 +1 @@
+{% include 'multiple_input.html' %}
\ No newline at end of file
diff --git a/src/templates/default/radio_select_option.html b/src/templates/default/radio_select_option.html
new file mode 100644
index 0000000..13a48ac
--- /dev/null
+++ b/src/templates/default/radio_select_option.html
@@ -0,0 +1 @@
+{% include 'multiple_input_option.html' %}
\ No newline at end of file
diff --git a/src/templates/default/select.html b/src/templates/default/select.html
new file mode 100644
index 0000000..312f353
--- /dev/null
+++ b/src/templates/default/select.html
@@ -0,0 +1,5 @@
+<select name="{{name|e}}"{% include 'attrs.html' with attrs %}>
+    {% for option in options %}
+        {% include option.template with option only %}
+    {% endfor %}
+</select>
\ No newline at end of file
diff --git a/src/templates/default/select_option.html b/src/templates/default/select_option.html
new file mode 100644
index 0000000..4efd53c
--- /dev/null
+++ b/src/templates/default/select_option.html
@@ -0,0 +1 @@
+<option value="{{value|e}}"{% include 'attrs.html' with attrs %}>{{label|e}}</option>
\ No newline at end of file
diff --git a/src/templates/default/text.html b/src/templates/default/text.html
new file mode 100644
index 0000000..3c0c8a9
--- /dev/null
+++ b/src/templates/default/text.html
@@ -0,0 +1 @@
+{% include 'input.html' %}
\ No newline at end of file
diff --git a/src/templates/default/textarea.html b/src/templates/default/textarea.html
new file mode 100644
index 0000000..dd9e452
--- /dev/null
+++ b/src/templates/default/textarea.html
@@ -0,0 +1 @@
+<textarea name="{{name|e}}"{% include "attrs.html" with attrs %}>{% if value is not empty %}{{value|e}}{% endif %}</textarea>
\ No newline at end of file
diff --git a/src/templates/default/url.html b/src/templates/default/url.html
new file mode 100644
index 0000000..3c0c8a9
--- /dev/null
+++ b/src/templates/default/url.html
@@ -0,0 +1 @@
+{% include 'input.html' %}
\ No newline at end of file
diff --git a/tests/unit/Errors/ErrorListTest.php b/tests/unit/Errors/ErrorListTest.php
index 5235fea..e65ac7d 100644
--- a/tests/unit/Errors/ErrorListTest.php
+++ b/tests/unit/Errors/ErrorListTest.php
@@ -13,17 +13,4 @@ public function testToString()
         $expected = '<ul class="errorlist"><li>1</li><li>2</li><li>3</li></ul>';
         $this->assertEquals((string) $error, $expected);
     }
-
-    public function testAsUL()
-    {
-        $error = new ErrorList(array(1, 2, 3));
-        $expected = '<ul class="errorlist"><li>1</li><li>2</li><li>3</li></ul>';
-        $this->assertEquals($error->asUL(), $expected);
-    }
-
-    public function testAsULEmptyArray()
-    {
-        $error = new ErrorList();
-        $this->assertEquals($error->asUL(), '');
-    }
 }
diff --git a/tests/unit/Fields/BoundFieldTest.php b/tests/unit/Fields/BoundFieldTest.php
index 7d70429..c0135b6 100644
--- a/tests/unit/Fields/BoundFieldTest.php
+++ b/tests/unit/Fields/BoundFieldTest.php
@@ -169,16 +169,21 @@ public function testLabelTagWithAttrs()
     }
 
 
-    public function testChoices()
+    public function testOptions()
     {
-        $field = new ChoiceField(["choices" => array("option1" => "Option1", "option2" => "Option2")]);
+        $field = new ChoiceField(["choices" => array("option1" => "Option1")]);
         $bound = new BoundField($this->simple_form, $field, "name");
 
-        $expected = array(
-            '<option value="option1">Option1</option>',
-            '<option value="option2">Option2</option>'
-        );
-
-        $this->assertEquals($expected, $bound->choices);
+        $expected = array(array(
+            "for" => "id_name_1",
+            "type" => null,
+            "name" => "name",
+            "value" => "option1",
+            "label" => "Option1",
+            "attrs" => array(),
+            "template" => "select_option.html"
+        ));
+
+        $this->assertEquals($expected, $bound->options);
     }
 }
diff --git a/tests/unit/PHPFormConfigTest.php b/tests/unit/PHPFormConfigTest.php
index d0c9bd4..ac96e16 100644
--- a/tests/unit/PHPFormConfigTest.php
+++ b/tests/unit/PHPFormConfigTest.php
@@ -26,20 +26,6 @@ public function testGetMessage()
         $this->assertNull($instance->getMessage("Inexistent"));
     }
 
-    public function testGetITemplate()
-    {
-        $this->assertEquals(PHPFormConfig::getITemplate("LABEL_REQUIRED"), '<span class="required">*</span>');
-        $this->assertNull(PHPFormConfig::getITemplate("Inexistent"));
-    }
-
-    public function testGetTemplate()
-    {
-        $instance = PHPFormConfig::getInstance();
-
-        $this->assertEquals($instance->getTemplate("LABEL_REQUIRED"), '<span class="required">*</span>');
-        $this->assertNull($instance->getTemplate("Inexistent"));
-    }
-
     public function testSetIMessages()
     {
         PHPFormConfig::setIMessages(array(
@@ -64,29 +50,4 @@ public function testSetMessages()
         $this->assertEquals("Invalid 2", $instance->getMessage("Invalid 2"));
         $this->assertEquals("Invalid 3", $instance->getMessage("Invalid 3"));
     }
-
-    public function testSetITemplates()
-    {
-        PHPFormConfig::setITemplates(array(
-            "Invalid 2" => "Invalid 2",
-            "Invalid 3" => "Invalid 3",
-        ));
-
-        $this->assertEquals('<span class="required">*</span>', PHPFormConfig::getITemplate("LABEL_REQUIRED"));
-        $this->assertEquals("Invalid 2", PHPFormConfig::getITemplate("Invalid 2"));
-        $this->assertEquals("Invalid 3", PHPFormConfig::getITemplate("Invalid 3"));
-    }
-
-    public function testSetTemplates()
-    {
-        $instance = PHPFormConfig::getInstance();
-        $instance->setTemplates(array(
-            "Invalid 2" => "Invalid 2",
-            "Invalid 3" => "Invalid 3",
-        ));
-
-        $this->assertEquals('<span class="required">*</span>', $instance->getTemplate("LABEL_REQUIRED"));
-        $this->assertEquals("Invalid 2", $instance->getTemplate("Invalid 2"));
-        $this->assertEquals("Invalid 3", $instance->getTemplate("Invalid 3"));
-    }
 }
diff --git a/tests/unit/Renderers/TwigRendererTest.php b/tests/unit/Renderers/TwigRendererTest.php
new file mode 100644
index 0000000..40f0c60
--- /dev/null
+++ b/tests/unit/Renderers/TwigRendererTest.php
@@ -0,0 +1,47 @@
+<?php
+namespace PHPForm\Unit\Renderers;
+
+use PHPUnit\Framework\TestCase;
+use Twig_TemplateWrapper;
+
+use PHPForm\Renderers\TwigRenderer;
+
+class TwigRendererTest extends TestCase
+{
+    public function setUp()
+    {
+        $this->renderer = new TwigRenderer(__DIR__ . "/templates/pack1", __DIR__ . "/templates/pack2");
+    }
+
+    public function testGetTempate()
+    {
+        $result = $this->renderer->getTemplate("template.html");
+        $this->assertInstanceOf(Twig_TemplateWrapper::class, $result);
+    }
+
+    public function testRender()
+    {
+        $result = $this->renderer->render("template.html", array("name" => "test"));
+        $expected = "Pack2 template test";
+
+        $this->assertEquals($expected, $result);
+    }
+
+    public function testRenderFallback()
+    {
+        $result = $this->renderer->render("template2.html", array("name" => "test"));
+        $expected = "Pack1 template2 test";
+
+        $this->assertEquals($expected, $result);
+    }
+
+    public function testRenderWithOnlyFallbackDefined()
+    {
+        $renderer = new TwigRenderer(__DIR__ . "/templates/pack1");
+
+        $result = $renderer->render("template.html", array("name" => "test"));
+        $expected = "Pack1 template test";
+
+        $this->assertEquals($expected, $result);
+    }
+}
diff --git a/tests/unit/Renderers/templates/pack1/template.html b/tests/unit/Renderers/templates/pack1/template.html
new file mode 100644
index 0000000..c6ce9c9
--- /dev/null
+++ b/tests/unit/Renderers/templates/pack1/template.html
@@ -0,0 +1 @@
+Pack1 template {{name}}
\ No newline at end of file
diff --git a/tests/unit/Renderers/templates/pack1/template2.html b/tests/unit/Renderers/templates/pack1/template2.html
new file mode 100644
index 0000000..1bebaa9
--- /dev/null
+++ b/tests/unit/Renderers/templates/pack1/template2.html
@@ -0,0 +1 @@
+Pack1 template2 {{name}}
\ No newline at end of file
diff --git a/tests/unit/Renderers/templates/pack2/template.html b/tests/unit/Renderers/templates/pack2/template.html
new file mode 100644
index 0000000..47c930f
--- /dev/null
+++ b/tests/unit/Renderers/templates/pack2/template.html
@@ -0,0 +1 @@
+Pack2 template {{name}}
\ No newline at end of file
diff --git a/tests/unit/Utils/Attributes.php b/tests/unit/Utils/Attributes.php
index 8fb7779..048ab15 100644
--- a/tests/unit/Utils/Attributes.php
+++ b/tests/unit/Utils/Attributes.php
@@ -1,5 +1,5 @@
 <?php
-namespace PHPForm\Unit\Validators;
+namespace PHPForm\Unit\Utils;
 
 use PHPUnit\Framework\TestCase;
 
@@ -7,14 +7,6 @@
 
 class AttributesTest extends TestCase
 {
-    public function testFlatatt()
-    {
-        $attrs = array("name" => "name", "type" => "text");
-        $this->assertEquals(Attributes::flatatt($attrs), 'name="name" type="text"');
-        $this->assertEquals(Attributes::flatatt(array()), '');
-        $this->assertEquals(Attributes::flatatt("string"), '');
-    }
-
     public function testPrettyName()
     {
         $this->assertEquals(Attributes::prettyName("label_name"), 'Label name');
diff --git a/tests/unit/Widgets/CheckboxInputTest.php b/tests/unit/Widgets/CheckboxInputTest.php
index dcefcb0..12833db 100644
--- a/tests/unit/Widgets/CheckboxInputTest.php
+++ b/tests/unit/Widgets/CheckboxInputTest.php
@@ -15,13 +15,13 @@ public function setUp()
     public function testGetContext()
     {
         $context = $this->widget->getContext("name", 10);
-        $this->assertEquals('checked="checked" id="id_name"', $context['attrs']);
+        $this->assertArraySubset(array("checked" => "checked"), $context['attrs']);
     }
 
     public function testGetContextWithFalseValue()
     {
         $context = $this->widget->getContext("name", false);
-        $this->assertEquals('id="id_name"', $context['attrs']);
+        $this->assertArrayNotHasKey("checked", $context['attrs']);
     }
 
     public function testRender()
diff --git a/tests/unit/Widgets/CheckboxSelectMultipleTest.php b/tests/unit/Widgets/CheckboxSelectMultipleTest.php
index ae495aa..2ee4eaa 100644
--- a/tests/unit/Widgets/CheckboxSelectMultipleTest.php
+++ b/tests/unit/Widgets/CheckboxSelectMultipleTest.php
@@ -15,14 +15,14 @@ public function setUp()
     public function testRender()
     {
         $expected =
-            '<div>' .
-                '<label for="id_name_1">' .
+            '<ul id="id_name">' .
+                '<li><label for="id_name_1">' .
                     '<input id="id_name_1" name="name[]" type="checkbox" value="option1"/> option1' .
-                '</label>' .
-                '<label for="id_name_2">' .
+                '</label></li>' .
+                '<li><label for="id_name_2">' .
                     '<input id="id_name_2" name="name[]" type="checkbox" value="option2"/> option2'.
-                '</label>' .
-            '</div>';
+                '</label></li>' .
+            '</ul>';
 
         $this->assertXmlStringEqualsXmlString($expected, $this->widget->render("name", null));
     }
@@ -30,14 +30,14 @@ public function testRender()
     public function testRenderChecked()
     {
         $expected =
-            '<div>' .
-                '<label for="id_name_1">' .
+            '<ul id="id_name">' .
+                '<li><label for="id_name_1">' .
                     '<input id="id_name_1" name="name[]" type="checkbox" checked="checked" value="option1"/> option1' .
-                '</label>' .
-                '<label for="id_name_2">' .
+                '</label></li>' .
+                '<li><label for="id_name_2">' .
                     '<input id="id_name_2" name="name[]" type="checkbox" value="option2"/> option2'.
-                '</label>' .
-            '</div>';
+                '</label></li>' .
+            '</ul>';
 
         $this->assertXmlStringEqualsXmlString($expected, $this->widget->render("name", "option1"));
     }
@@ -52,20 +52,20 @@ public function testRenderMultipleChecked()
         ]);
 
         $expected =
-            '<div>' .
-                '<label for="id_name_1">' .
+            '<ul id="id_name">' .
+                '<li><label for="id_name_1">' .
                     '<input id="id_name_1" name="name[]" type="checkbox" value="option1"/> option1' .
-                '</label>' .
-                '<label for="id_name_2">' .
+                '</label></li>' .
+                '<li><label for="id_name_2">' .
                     '<input id="id_name_2" name="name[]" type="checkbox" checked="checked" value="option2"/> option2'.
-                '</label>' .
-                '<label for="id_name_3">' .
+                '</label></li>' .
+                '<li><label for="id_name_3">' .
                     '<input id="id_name_3" name="name[]" type="checkbox" checked="checked" value="option3"/> option3'.
-                '</label>' .
-                '<label for="id_name_4">' .
+                '</label></li>' .
+                '<li><label for="id_name_4">' .
                     '<input id="id_name_4" name="name[]" type="checkbox" value="option4"/> option4'.
-                '</label>' .
-            '</div>';
+                '</label></li>' .
+            '</ul>';
 
         $this->assertXmlStringEqualsXmlString($expected, $widget->render("name", ["option2", "option3"]));
     }
diff --git a/tests/unit/Widgets/ChoiceWidgetTest.php b/tests/unit/Widgets/ChoiceWidgetTest.php
index ad514f1..3f1ba14 100644
--- a/tests/unit/Widgets/ChoiceWidgetTest.php
+++ b/tests/unit/Widgets/ChoiceWidgetTest.php
@@ -19,12 +19,15 @@ public function setUp()
         $this->widget = $this->getMockForAbstractClass(ChoiceWidget::class, array($attrs));
     }
 
-    public function testFormatValue()
+    public function testSetChoices()
     {
-        // $this->assertEquals([], $this->widget->formatValue(""));
-        // $this->assertEquals([], $this->widget->formatValue(null));
-        // $this->assertEquals([], $this->widget->formatValue([]));
-        // $this->assertEquals(["1", "2"], $this->widget->formatValue([1, 2]));
-        $this->assertEquals(1, 1);
+        $choices = array(
+            "option1" => "Option 1",
+            "option2" => "Option 2",
+        );
+
+        $this->widget->setChoices($choices);
+
+        $this->assertAttributeEquals($choices, "choices", $this->widget);
     }
 }
diff --git a/tests/unit/Widgets/InputTest.php b/tests/unit/Widgets/InputTest.php
index 2cfdaaf..30ab75f 100644
--- a/tests/unit/Widgets/InputTest.php
+++ b/tests/unit/Widgets/InputTest.php
@@ -18,7 +18,7 @@ public function testRender()
     {
         $stub = $this->getMockForAbstractClass(Input::class);
         $result = $stub->render("name", "value");
-        $expected = '<input type="NULL" id="id_name" name="name" value="value"/>';
+        $expected = '<input type="" id="id_name" name="name" value="value"/>';
         $this->assertXmlStringEqualsXmlString($result, $expected);
     }
 
@@ -26,15 +26,15 @@ public function testRenderWithoutValue()
     {
         $stub = $this->getMockForAbstractClass(Input::class);
         $result = $stub->render("name", null);
-        $expected = '<input type="NULL" id="id_name" name="name" />';
+        $expected = '<input type="" id="id_name" name="name" />';
         $this->assertXmlStringEqualsXmlString($result, $expected);
     }
 
     public function testRenderWithExtraAttrs()
     {
         $stub = $this->getMockForAbstractClass(Input::class);
-        $result = $stub->render("name", "value", array("class" => "input"));
-        $expected = '<input type="NULL" id="id_name" name="name" value="value" class="input"/>';
+        $result = $stub->render("name", "value", null, array("class" => "input"));
+        $expected = '<input type="" id="id_name" name="name" value="value" class="input"/>';
         $this->assertXmlStringEqualsXmlString($result, $expected);
     }
 }
diff --git a/tests/unit/Widgets/RadioSelectTest.php b/tests/unit/Widgets/RadioSelectTest.php
index b4e5bac..b73afe4 100644
--- a/tests/unit/Widgets/RadioSelectTest.php
+++ b/tests/unit/Widgets/RadioSelectTest.php
@@ -15,14 +15,14 @@ public function setUp()
     public function testRender()
     {
         $expected =
-            '<div>' .
-                '<label for="id_name_1">' .
+            '<ul id="id_name">' .
+                '<li><label for="id_name_1">' .
                     '<input id="id_name_1" name="name" type="radio" value="option1"/> option1' .
-                '</label>' .
-                '<label for="id_name_2">' .
+                '</label></li>' .
+                '<li><label for="id_name_2">' .
                     '<input id="id_name_2" name="name" type="radio" value="option2"/> option2'.
-                '</label>' .
-            '</div>';
+                '</label></li>' .
+            '</ul>';
 
         $this->assertXmlStringEqualsXmlString($expected, $this->widget->render("name", null));
     }
@@ -30,14 +30,14 @@ public function testRender()
     public function testRenderChecked()
     {
         $expected =
-            '<div>' .
-                '<label for="id_name_1">' .
+            '<ul id="id_name">' .
+                '<li><label for="id_name_1">' .
                     '<input id="id_name_1" name="name" type="radio" checked="checked" value="option1"/> option1' .
-                '</label>' .
-                '<label for="id_name_2">' .
+                '</label></li>' .
+                '<li><label for="id_name_2">' .
                     '<input id="id_name_2" name="name" type="radio" value="option2"/> option2'.
-                '</label>' .
-            '</div>';
+                '</label></li>' .
+            '</ul>';
 
         $this->assertXmlStringEqualsXmlString($expected, $this->widget->render("name", "option1"));
         $this->assertXmlStringEqualsXmlString($expected, $this->widget->render("name", ["option1", "option2"]));
diff --git a/tests/unit/Widgets/URLInputTest.php b/tests/unit/Widgets/URLInputTest.php
index 912577b..e8c517a 100644
--- a/tests/unit/Widgets/URLInputTest.php
+++ b/tests/unit/Widgets/URLInputTest.php
@@ -7,17 +7,20 @@
 
 class URLInputTest extends TestCase
 {
+    public function setUp()
+    {
+        $this->widget = new URLInput();
+    }
+
     public function testGetContext()
     {
-        $widget = new URLInput();
-        $context = $widget->getContext("name", "url");
+        $context = $this->widget->getContext("name", "url");
         $this->assertEquals($context["type"], "url");
     }
 
     public function testRender()
     {
-        $widget = new URLInput();
-        $render = $widget->render("name", "url");
-        $this->assertXmlStringEqualsXmlString($render, '<input type="url" id="id_name" name="name" value="url"/>');
+        $expected = $this->widget->render("name", "url");
+        $this->assertXmlStringEqualsXmlString($expected, '<input type="url" id="id_name" name="name" value="url"/>');
     }
 }
diff --git a/tests/unit/Widgets/WidgetTest.php b/tests/unit/Widgets/WidgetTest.php
deleted file mode 100644
index e69de29..0000000