diff --git a/about.png b/about.png
index d7cf03f..b1dc22c 100644
Binary files a/about.png and b/about.png differ
diff --git a/lib/headers/expressions/container.hpp b/lib/headers/expressions/container.hpp
index 79398a8..e555821 100644
--- a/lib/headers/expressions/container.hpp
+++ b/lib/headers/expressions/container.hpp
@@ -8,22 +8,10 @@
 #include <expressions/result.hpp>
 
 namespace expressions {
-    class container : public std::enable_shared_from_this<container> {
+    struct container {
         std::string regex_;
         std::vector<std::string> arguments_{};
 
-    public:
-        /**
-         * Expression constructor
-         *
-         * @param regex
-         * @param arguments
-         */
-        container(
-            std::string regex,
-            std::vector<std::string> arguments
-        );
-
         /**
          * Get the regex
          *
@@ -46,8 +34,8 @@ namespace expressions {
          * @param input
          * @return
          */
-        std::shared_ptr<result>
-        query(const std::string &input);
+        result
+        query(const std::string &input) const;
 
         /**
          * Creates a expression from strings
@@ -55,7 +43,7 @@ namespace expressions {
          * @param input
          * @return std::shared_ptr<expression>
          */
-        static std::shared_ptr<container>
+        static container
         from_string(const std::string &input);
     };
 }
diff --git a/lib/headers/expressions/result.hpp b/lib/headers/expressions/result.hpp
index d0fc89a..e62711a 100644
--- a/lib/headers/expressions/result.hpp
+++ b/lib/headers/expressions/result.hpp
@@ -2,24 +2,13 @@
 
 #include <memory>
 #include <unordered_map>
+#include <optional>
 
 namespace expressions {
-    class result : public std::enable_shared_from_this<result> {
+    struct result {
         bool _matches = false;
         std::unordered_map<std::string, std::string> _bindings;
 
-    public:
-        /**
-         * Expression result constructor
-         *
-         * @param matches
-         * @param bindings
-         */
-        result(
-            bool matches,
-            std::unordered_map<std::string, std::string> bindings
-        );
-
         /**
          * Get matches
          *
@@ -35,5 +24,14 @@ namespace expressions {
          */
         std::unordered_map<std::string, std::string>
         bindings() const;
+
+        /**
+         * Get parameter
+         *
+         * @param name
+         * @return
+         */
+        std::string
+        get(const std::string & name) const;
     };
 }
diff --git a/lib/sources/container.cpp b/lib/sources/container.cpp
index aec90cb..c8fcb80 100644
--- a/lib/sources/container.cpp
+++ b/lib/sources/container.cpp
@@ -1,10 +1,6 @@
 #include <expressions/container.hpp>
 
 namespace expressions {
-    container::container(std::string regex, std::vector<std::string> arguments)
-        : regex_(std::move(regex)), arguments_(std::move(arguments)) {
-    }
-
     std::string container::get_regex() const {
         return regex_;
     }
@@ -13,7 +9,7 @@ namespace expressions {
         return arguments_;
     }
 
-    std::shared_ptr<result> container::query(const std::string &input) {
+    result container::query(const std::string &input) const {
         std::unordered_map<std::string, std::string> _bindings;
         const std::regex _pattern(regex_);
         bool _matches = false;
@@ -26,10 +22,10 @@ namespace expressions {
                 ++_iterator;
             }
         }
-        return std::make_shared<result>(_matches, _bindings);
+        return { ._matches = _matches, ._bindings = _bindings  };
     }
 
-    std::shared_ptr<container> container::from_string(const std::string &input) {
+    container container::from_string(const std::string &input) {
         std::size_t _open = input.find('{');
         std::size_t _close = input.find('}');
         std::size_t _position = 0;
@@ -38,14 +34,14 @@ namespace expressions {
         std::string _regex;
 
         if (_open == std::string::npos && _close == std::string::npos)
-            return std::make_shared<container>(std::string{input.data()}, _arguments);
+            return { .regex_ = std::string{ input }, .arguments_ = _arguments };
 
         while (_open != std::string::npos && _close != std::string::npos) {
             _regex.append(input.substr(_position, _open - _position));
             std::string _value{input.substr(_open + 1, _close - _open - 1)};
 
             if (std::find(_arguments.begin(), _arguments.end(), _value) != _arguments.end())
-                throw std::runtime_error("groups can't be repeated ... ");
+                throw std::runtime_error("The provided input contains repeated arguments.");
 
             _regex.append(R"(([a-zA-Z0-9\-_]+))");
             _arguments.emplace_back(_value);
@@ -53,11 +49,11 @@ namespace expressions {
             _position = _close + 1;
             _open = input.find('{', _close);
             _close = input.find('}', _open);
-
-            if (_open == std::string::npos && _close == std::string::npos && _position != input.size())
-                _regex.append(input.substr(_position, input.size() - _position));
         }
 
-        return std::make_shared<container>(_regex, _arguments);
+        if (_position != input.size())
+            _regex.append(input.substr(_position, input.size() - _position));
+
+        return { .regex_ = _regex , .arguments_ = _arguments };
     }
 }
diff --git a/lib/sources/result.cpp b/lib/sources/result.cpp
index b52d781..752148a 100644
--- a/lib/sources/result.cpp
+++ b/lib/sources/result.cpp
@@ -1,10 +1,6 @@
 #include <expressions/result.hpp>
 
 namespace expressions {
-    result::result(const bool matches, std::unordered_map<std::string, std::string> bindings)
-    : _matches(matches), _bindings(std::move(bindings)) {
-    }
-
     bool result::matches() const {
         return _matches;
     }
@@ -12,4 +8,11 @@ namespace expressions {
     std::unordered_map<std::string, std::string> result::bindings() const {
         return _bindings;
     }
+
+    std::string
+    result::get(const std::string &name) const {
+        if (_bindings.contains(name))
+            return _bindings.at(name);
+        throw std::runtime_error("The provided argument doesn't exists");
+    }
 }
diff --git a/tests/implementation_test.cc b/tests/implementation_test.cc
index b27ac4a..d9cc5dc 100644
--- a/tests/implementation_test.cc
+++ b/tests/implementation_test.cc
@@ -5,21 +5,23 @@ TEST(Expressions, Assertions) {
     using namespace expressions;
 
     const auto _non_empty_expression = container::from_string("/users/{user}/details");
-    ASSERT_FALSE(_non_empty_expression->get_arguments().empty());
-    ASSERT_EQ(_non_empty_expression->get_arguments().size(), 1);
-    ASSERT_EQ(_non_empty_expression->get_arguments().at(0), "user");
+
+    ASSERT_FALSE(_non_empty_expression.get_arguments().empty());
+    ASSERT_EQ(_non_empty_expression.get_arguments().size(), 1);
+    ASSERT_EQ(_non_empty_expression.get_arguments().at(0), "user");
 
     const auto _empty_expression = container::from_string("/ping");
-    ASSERT_TRUE(_empty_expression->get_arguments().empty());
-    ASSERT_EQ(_empty_expression->get_regex(), "/ping");
+    ASSERT_TRUE(_empty_expression.get_arguments().empty());
+    ASSERT_EQ(_empty_expression.get_regex(), "/ping");
+
+    const auto _non_empty_string_expression_result = _non_empty_expression.query("/users/80bdc6d1-524e-411a-b316-976a65a3ed3c/details");
 
-    const auto _non_empty_string_expression_result = _non_empty_expression->query("/users/80bdc6d1-524e-411a-b316-976a65a3ed3c/details");
-    ASSERT_TRUE(_non_empty_string_expression_result->matches());
-    ASSERT_FALSE(_non_empty_string_expression_result->bindings().empty());
-    ASSERT_EQ(_non_empty_string_expression_result->bindings().at("user"), "80bdc6d1-524e-411a-b316-976a65a3ed3c");
+    ASSERT_TRUE(_non_empty_string_expression_result.matches());
+    ASSERT_FALSE(_non_empty_string_expression_result.bindings().empty());
+    ASSERT_EQ(_non_empty_string_expression_result.get("user"), "80bdc6d1-524e-411a-b316-976a65a3ed3c");
 
-    const auto _non_empty_integer_expression_result = _non_empty_expression->query("/users/1337/details");
-    ASSERT_TRUE(_non_empty_integer_expression_result->matches());
-    ASSERT_FALSE(_non_empty_integer_expression_result->bindings().empty());
-    ASSERT_EQ(_non_empty_integer_expression_result->bindings().at("user"), "1337");
+    const auto _non_empty_integer_expression_result = _non_empty_expression.query("/users/1337/details");
+    ASSERT_TRUE(_non_empty_integer_expression_result.matches());
+    ASSERT_FALSE(_non_empty_integer_expression_result.bindings().empty());
+    ASSERT_EQ(_non_empty_integer_expression_result.get("user"), "1337");
 }