diff --git a/include/Arg.hpp b/include/Arg.hpp
index 4809ff1..96c0cba 100644
--- a/include/Arg.hpp
+++ b/include/Arg.hpp
@@ -17,6 +17,7 @@ class Arg {
     Arg& help(const std::string& help);
     Arg& required(bool is_required);
     Arg& is_flag();
+    Arg& accepts_many();
     Arg& default_value(const std::string& default_val);
     Arg& from_env(const char* env_var_name);
     Arg& auto_env();
@@ -33,6 +34,7 @@ class Arg {
     std::string help_;
     bool is_required_;
     bool is_flag_;
+    bool accepts_many_;
     std::string env_name_;
     bool auto_env_;
     // std::string auto_env_name_;
@@ -80,7 +82,7 @@ class Arg {
       this->is_required_ = is_required;
     }
 
-    // takes_value_
+    // is_flag_
     [[nodiscard]] inline bool get__is_flag() const {
       return this->is_flag_;
     }
@@ -88,6 +90,14 @@ class Arg {
       this->is_flag_ = takes_value;
     }
 
+    // accepts_many_
+    [[nodiscard]] inline bool get__accepts_many() const {
+      return this->accepts_many_;
+    }
+    inline void set__accepts_many(const bool& accepts_many) {
+      this->accepts_many_ = accepts_many;
+    }
+    
     // env_name_
     [[nodiscard]] inline const std::string& get__env_name() const {
       return this->env_name_;
@@ -107,7 +117,7 @@ class Arg {
     // auto_env_name_
     // [[nodiscard]] inline const std::string get__auto_env_name() const {
     //   std::string env_name = PROGRAM_NAME() + '_' + this->get__name();
-    //   std::transform(env_name.begin(), env_name.end(), env_name.begin(), [](const unsigned char& c) { return std::toupper(c); });
+    //   to_upper(env_name);
     //   return env_name;
     // }
 
diff --git a/include/Parser.hpp b/include/Parser.hpp
index fc8d483..dd7b0c7 100644
--- a/include/Parser.hpp
+++ b/include/Parser.hpp
@@ -3,46 +3,108 @@
 #include "Arg.hpp"
 #include "utils.hpp"
 
+#include <optional>
+#include <string_view>
+#include <type_traits>
+#include <system_error>
+#include <cstdlib>
+#include <charconv>
 #include <iostream>
 #include <optional>
 #include <string>
-#include <unordered_map>
 #include <vector>
 
+template<typename T>
+struct Parse {
+    static std::optional<T> parse(std::string_view s) {
+        if constexpr (std::is_integral_v<T>) {
+            T value;
+            auto [ptr, ec] = std::from_chars(s.data(), s.data() + s.size(), value);
+            if (ec == std::errc()) return value;
+            return std::nullopt;
+        }
+        else if constexpr (std::is_same_v<T, float>) {
+            char* end = nullptr;
+            float value = std::strtof(s.data(), &end);
+            if (end == s.data() + s.size()) return value;
+            return std::nullopt;
+        }
+        else if constexpr (std::is_same_v<T, double>) {
+            char* end = nullptr;
+            double value = std::strtod(s.data(), &end);
+            if (end == s.data() + s.size()) return value;
+            return std::nullopt;
+        }
+        else if constexpr (std::is_same_v<T, long double>) {
+            char* end = nullptr;
+            long double value = std::strtold(s.data(), &end);
+            if (end == s.data() + s.size()) return value;
+            return std::nullopt;
+        }
+        else {
+            static_assert(sizeof(T) == 0, "No Parse<T> specialization defined for this type");
+        }
+    }
+};
+
+template<>
+struct Parse<std::string> {
+    static std::optional<std::string> parse(std::string_view s) {
+        return std::string(s);
+    }
+};
+
+template<>
+struct Parse<bool> {
+    static std::optional<bool> parse(std::string_view s) {
+      auto as_int = Parse<int>::parse(s).value();
+      return as_int;
+    }
+};
+
+template<typename T>
+concept Parseable = requires(std::string_view s) {
+    { Parse<T>::parse(s) } -> std::convertible_to<std::optional<T>>;
+};
+
 class ClapParser {
   public:
     void add_arg(const Arg& arg);
     void parse(const int& argc, char* argv[]);
     void print_help() const;
 
-    template <typename T> inline std::optional<T> get_one_as(const std::string& name) {
+    template <typename T>
+    requires Parseable<T>
+    inline std::optional<T> get_one_as(const std::string& name) {
         Arg* arg = ok_or(ClapParser::find_arg(*this, "--" + name), []{ return std::nullopt; });
 
-        if (auto arg_value = arg->get__value(); arg_value) {
-            T value;
-            std::istringstream(*arg_value) >> value;
-            return value;
-        }
-        return std::nullopt;
+        // if (auto arg_value = arg->get__value(); arg_value) {
+        //     T value;
+        //     std::istringstream(*arg_value) >> value;
+        //     return value;
+        // }
+        // return std::nullopt;
+
+        return Parse<T>::parse(arg->get__value().value());
     }
 
     static void print_parser(std::ostream& os, const ClapParser& parser, int indent);
     friend std::ostream& operator<<(std::ostream& os, const ClapParser& parser);
   private:
     std::vector<Arg> args_;
-    std::unordered_map<std::string, std::string> values_;
     std::string program_name_;
 
     // Helper methods
-    inline bool is_option(const std::string& token) const ;
-    inline bool is_long_option(const std::string& token) const ;
-    inline bool is_short_option(const std::string& token) const ;
+    static bool is_option(const std::string& token);
+    static bool is_long_option(const std::string& token);
+    static bool is_short_option(const std::string& token);
     static std::optional<Arg*> find_arg(ClapParser& parser, const std::string& name);
     std::vector<Arg> get_positional_args() const;
     void apply_defaults();
 
-    void parse_options(const std::vector<std::string>& args);
+    void parse_cli_args(const std::vector<std::string>& args);
     void check_env();
     void parse_positional_args(const std::vector<std::string>& args);
+    static void parse_value_for_non_flag(Arg* arg, size_t& cli_index, const std::vector<std::string>& args);
     void handle_missing_positional(const Arg& arg);
 };
diff --git a/include/utils.hpp b/include/utils.hpp
index cfd0dec..387a618 100644
--- a/include/utils.hpp
+++ b/include/utils.hpp
@@ -1,9 +1,10 @@
 #pragma once
 
+#include <algorithm>
 #include <optional>
+#include <sstream>
 #include <stdexcept>
 #include <string>
-#include <sstream>
 
 template <typename T, typename E>
 inline T ok_or(std::optional<T> opt, E&& err) {
@@ -44,3 +45,7 @@ inline void print_indent(std::ostream& os, int indent_level) {
     for (int i = 0; i < indent_level; ++i)
         os << '\t';
 }
+
+inline void to_upper(std::string &s) {
+    std::ranges::transform(s, s.begin(), [](const unsigned char& c) { return std::toupper(c); });
+}
diff --git a/src/Arg.cpp b/src/Arg.cpp
index b7766e9..ac18a58 100644
--- a/src/Arg.cpp
+++ b/src/Arg.cpp
@@ -12,6 +12,7 @@ Arg::Arg(const std::string& name) :
     help_(""),
     is_required_(false),
     is_flag_(false),
+    accepts_many_(false),
     env_name_(""),
     auto_env_(false),
     default_value_(""),
@@ -31,11 +32,15 @@ Arg& Arg::required(bool is_required) {
     is_required_ = is_required;
     return *this;
 }
-Arg& Arg::is_flag()  {
+Arg& Arg::is_flag() {
     is_flag_ = true;
     default_value_ = "0";
     return *this;
 }
+Arg& Arg::accepts_many() {
+    accepts_many_ = true;
+    return *this;
+}
 Arg& Arg::default_value(const std::string& default_value) {
     default_value_ = default_value;
     return *this;
@@ -69,6 +74,7 @@ void Arg::print_arg(std::ostream& os, const Arg& arg, int indent) {
     print_indent(os, indent + 1); os << "help: \"" << arg.help_ << "\",\n";
     print_indent(os, indent + 1); os << "required: " << std::boolalpha << arg.is_required_ << ",\n";
     print_indent(os, indent + 1); os << "is_flag: " << std::boolalpha << arg.is_flag_ << ",\n";
+    print_indent(os, indent + 1); os << "accepts_many: " << std::boolalpha << arg.accepts_many_ << ",\n";
     print_indent(os, indent + 1); os << "default: \"" << arg.default_value_ << "\",\n";
     print_indent(os, indent + 1); os << "value: ";
     if (arg.value_)
diff --git a/src/Parser.cpp b/src/Parser.cpp
index dcdfc44..a4cc87f 100644
--- a/src/Parser.cpp
+++ b/src/Parser.cpp
@@ -3,11 +3,13 @@
 #include "utils.hpp"
 
 #include <cctype>
+#include <cstddef>
 #include <cstdlib>
 #include <iostream>
 #include <stdexcept>
 #include <string>
 #include <algorithm>
+#include <vector>
 
 void ClapParser::parse(const int& argc, char* argv[]) {
     const std::string& raw_program_name = argv[0];
@@ -22,8 +24,7 @@ void ClapParser::parse(const int& argc, char* argv[]) {
 
     this->apply_defaults();
     this->check_env();
-    this->parse_options(args); // parse from cli (argc, argv)
-    // parse_positional_args(args);
+    this->parse_cli_args(args); // parse from cli (argc, argv)
 
     // Validate all arguments that need values received them
     for (const auto& arg : args_) {
@@ -36,7 +37,7 @@ void ClapParser::parse(const int& argc, char* argv[]) {
 
 void ClapParser::add_arg(const Arg& arg) { args_.emplace_back(arg); }
 
-void ClapParser::parse_options(const std::vector<std::string>& args) {
+void ClapParser::parse_cli_args(const std::vector<std::string>& args) {
     for (size_t i = 0; i < args.size(); ++i) {
         const auto& token = args.at(i);
 
@@ -46,24 +47,38 @@ void ClapParser::parse_options(const std::vector<std::string>& args) {
         }
 
         auto arg = ok_or_throw_str(ClapParser::find_arg(*this, token), "unknown option: \'" + token);
+
         if (!arg->get__is_flag()) {
-            if (i + 1 < args.size() && !is_option(args[i + 1])) {
-                arg->set__value(args.at(i + 1));
-                i++; // Skip the value in the next iteration
-            }  else {
-                throw std::runtime_error("option '" + token + "' requires a value but none was provided");
-            }
+            ClapParser::parse_value_for_non_flag(arg, i, args);
         } else {
             arg->set__value("1");
         }
     }
 }
 
+void ClapParser::parse_value_for_non_flag(Arg* arg, size_t& cli_index, const std::vector<std::string>& args) {
+    if (cli_index + 1 < args.size() && !is_option(args.at(cli_index + 1))) {
+        if (arg->get__accepts_many()) {
+            std::string value;
+            while (cli_index + 1 < args.size() && !is_option(args.at(cli_index + 1))) {
+                value += args.at(cli_index + 1) + ' ';
+                cli_index++;
+            }
+            arg->set__value(value);
+        } else {
+            arg->set__value(args.at(cli_index + 1));
+            cli_index++; // Skip the value in the next iteration
+        }
+    }  else {
+        throw std::runtime_error("option '" + arg->get__name() + "' requires a value but none was provided");
+    }
+}
+
 void ClapParser::check_env() {
     for (auto& arg : args_) {
         if (arg.get__auto_env()) {
             std::string env_name = this->program_name_ + '_' + arg.get__name();
-            std::transform(env_name.begin(), env_name.end(), env_name.begin(), [](const unsigned char& c) { return std::toupper(c); });
+            to_upper(env_name);
             auto value_from_env = std::getenv(env_name.c_str());
             if (value_from_env) {
                 arg.set__value(value_from_env);
@@ -78,45 +93,17 @@ void ClapParser::check_env() {
     }
 };
 
-// void ClapParser::parse_positional_args(const std::vector<std::string>& args) {
-//     std::vector<std::string> positional_args;
-
-//     // Collect positional arguments (tokens not starting with '-')
-//     for (const auto& token : args) {
-//         if (!is_option(token)) {
-//             positional_args.push_back(token);
-//         }
-//     }
-
-//     // Assign positional arguments to their respective slots
-//     auto positional_specs = get_positional_args();
-//     for (size_t j = 0; j < positional_specs.size(); ++j) {
-//         if (j < positional_args.size()) {
-//             values_[positional_specs[j].name()] = positional_specs[j].convert(positional_args[j]);
-//         } else {
-//             handle_missing_positional(positional_specs[j]);
-//         }
-//     }
-// }
-
-void ClapParser::handle_missing_positional(const Arg& arg) {
-    if (arg.get__is_required()) {
-        throw std::runtime_error("missing required positional argument: " + arg.get__name());
-    }
-    if (arg.has_default()) {
-        values_[arg.get__name()] = std::string(arg.get__default_value());
-    }
+bool ClapParser::is_option(const std::string& token) {
+    return token.substr(0, 2) == "--" || (token[0] == '-' && token.size() > 1);
 }
-
-  inline bool ClapParser::is_option(const std::string& token) const {
-      return token.substr(0, 2) == "--" || (token[0] == '-' && token.size() > 1);
-  }
   
-  inline bool ClapParser::is_long_option(const std::string& token) const { return token.substr(0, 2) == "--"; }
+bool ClapParser::is_long_option(const std::string& token) {
+    return token.substr(0, 2) == "--";
+}
   
-  inline bool ClapParser::is_short_option(const std::string& token) const {
-      return token[0] == '-' && token.size() > 1 && token[1] != '-';
-  }
+bool ClapParser::is_short_option(const std::string& token) {
+    return token[0] == '-' && token.size() > 1 && token[1] != '-';
+}
 
 void ClapParser::print_help() const {
     std::cout << "Usage: " << this->program_name_ << " [OPTIONS]";
@@ -202,10 +189,6 @@ void ClapParser::print_parser(std::ostream& os, const ClapParser& parser, int in
     }
     print_indent(os, indent + 1); os << "],\n";
 
-    print_indent(os, indent + 1); os << "values: {\n";
-    for (const auto& [key, val] : parser.values_) {
-        print_indent(os, indent + 2); os << "\"" << key << "\": \"" << val << "\",\n";
-    }
     print_indent(os, indent + 1); os << "}\n";
 
     print_indent(os, indent); os << "}";
diff --git a/tests/test_combo.cpp b/tests/test_combo.cpp
index b07170d..9aa7ab0 100644
--- a/tests/test_combo.cpp
+++ b/tests/test_combo.cpp
@@ -27,6 +27,7 @@ int main(int argc, char* argv[]) {
   auto actual_val = ok_or_throw_str(p.get_one_as<int>("val"), "test argument: 'val' is missing");
   auto actual_boolean = ok_or_throw_str(p.get_one_as<bool>("flag"), "test argument: 'flag' is missing");
 
+  std::cerr << p << '\n';
   assert(actual_val == expected_val);
   assert(actual_boolean == expected_boolean);
   return 0;
diff --git a/tests/test_priority.cpp b/tests/test_priority.cpp
index 49d3c89..722a4a6 100644
--- a/tests/test_priority.cpp
+++ b/tests/test_priority.cpp
@@ -2,7 +2,6 @@
 #include "Parser.hpp"
 #include "Arg.hpp"
 #include "utils.hpp"
-#include <cstdio>
 #include <cstdlib>
 #include <cassert>
 #include <iostream>