diff --git a/include/jwt/detail/meta.hpp b/include/jwt/detail/meta.hpp
index 10f71c7..8f19d75 100644
--- a/include/jwt/detail/meta.hpp
+++ b/include/jwt/detail/meta.hpp
@@ -134,7 +134,12 @@ struct is_sequence_concept: std::false_type
 template <typename T>
 struct is_sequence_concept<T,
   void_t<
-    std::enable_if_t<std::is_array<std::decay_t<T>>::value>
+    std::enable_if_t<std::is_array<std::decay_t<T>>::value>,
+
+    std::enable_if_t<
+      std::is_constructible<jwt::string_view, 
+                            std::remove_reference_t<decltype(*std::begin(std::declval<T&>()))>>::value
+    >
   >
   >: std::true_type
 {
@@ -147,8 +152,11 @@ struct is_sequence_concept<T,
       std::is_base_of<
         std::forward_iterator_tag,
         typename std::remove_reference_t<T>::iterator::iterator_category
-      >::value
-    >,
+      >::value>,
+
+      std::enable_if_t<
+        std::is_constructible<jwt::string_view, typename std::remove_reference_t<T>::value_type>::value
+      >,
 
     decltype(
       std::declval<T&>().begin(),
diff --git a/include/jwt/exceptions.hpp b/include/jwt/exceptions.hpp
index 3c5af44..a614f15 100644
--- a/include/jwt/exceptions.hpp
+++ b/include/jwt/exceptions.hpp
@@ -2,6 +2,7 @@
 #define CPP_JWT_EXCEPTIONS_HPP
 
 #include <new>
+#include <string>
 
 namespace jwt {
 
@@ -42,6 +43,18 @@ public:
   }
 };
 
+/**
+ */
+class VerificationError final: public std::runtime_error
+{
+public:
+  /**
+   */
+  VerificationError(std::string msg)
+    : std::runtime_error(std::move(msg))
+  {
+  }
+};
 
 } // END namespace jwt
 
diff --git a/include/jwt/impl/jwt.ipp b/include/jwt/impl/jwt.ipp
index ea1095e..bf6a260 100644
--- a/include/jwt/impl/jwt.ipp
+++ b/include/jwt/impl/jwt.ipp
@@ -2,6 +2,7 @@
 #define JWT_IPP
 
 #include "jwt/detail/meta.hpp"
+#include <algorithm>
 
 namespace jwt {
 
@@ -100,6 +101,9 @@ void jwt_payload::decode(const string_view enc_str, std::error_code& ec) noexcep
     ec = DecodeErrc::JsonParseError;
     return;
   }
+
+  //validate the fields
+  //TODO:
   return;
 }
 
@@ -140,15 +144,12 @@ std::string jwt_signature::encode(const jwt_header& header,
   return jwt_msg;
 }
 
-bool jwt_signature::verify(const jwt_header& header,
+verify_result_t jwt_signature::verify(const jwt_header& header,
                            const string_view hdr_pld_sign,
                            const string_view jwt_sign)
 {
-  //TODO: is bool the right choice ?
   verify_func_t verify_fn = get_verify_algorithm_impl(header);
-  verify_fn(key_, hdr_pld_sign, jwt_sign);
-
-  return true;
+  return verify_fn(key_, hdr_pld_sign, jwt_sign);
 }
 
 
@@ -399,19 +400,57 @@ jwt_object decode(const string_view enc_str,
   set_decode_params(dparams, std::forward<Args>(args)...);
 
   jwt_object obj;
-
   auto parts = jwt_object::three_parts(enc_str);
+
   //throws decode error
   obj.header(jwt_header{parts[0]});
+
   //throws decode error
   obj.payload(jwt_payload{parts[1]});
 
+  //TODO: Should be part of jwt_object::verify
+  if (dparams.verify) {
+    //Verify if the algorithm set in the header
+    //is any of the one expected by the client.
+    auto fitr = std::find_if(algos.get().begin(), algos.get().end(),
+                             [&](const auto& elem) {
+                                return jwt::str_to_alg(elem) == obj.header().algo();
+                             });
+
+    if (fitr == algos.get().end()) {
+      throw VerificationError("Provided algorithms do not match with header");
+    }
+
+    //Check for the expiry timings
+    if (obj.payload().has_claim("exp")) {
+      auto curr_time = std::chrono::duration_cast<
+                          std::chrono::seconds>(std::chrono::system_clock::now().time_since_epoch()).count();
+      auto p_exp = obj.payload()
+                      .get_claim_value(registered_claims::expiration)
+                      .get<uint64_t>();
+
+      std::cout << curr_time << " :: " << p_exp << std::endl;
+
+      if (p_exp < curr_time) {
+        throw VerificationError("Token expired");
+      }
+    } 
+  }
+
   jwt_signature jsign{key};
  
   // Length of the encoded header and payload only.
   // Addition of '1' to account for the '.' character.
   auto l = parts[0].length() + 1 + parts[1].length();
-  auto res = jsign.verify(obj.header(), enc_str.substr(0, l), parts[2]);
+
+  verify_result_t res = jsign.verify(obj.header(), enc_str.substr(0, l), parts[2]);
+  if (res.second) {
+    throw VerificationError(res.second.message());
+  }
+
+  if (!res.first) {
+    throw VerificationError("Verification failed due to unknown reason");
+  }
 
   return obj; 
 }
diff --git a/include/jwt/jwt.hpp b/include/jwt/jwt.hpp
index 16ebcae..689ddfb 100644
--- a/include/jwt/jwt.hpp
+++ b/include/jwt/jwt.hpp
@@ -306,6 +306,7 @@ public: // Exposed APIs
   {
     // Duplicate claim names not allowed
     // if overwrite flag is set to true.
+    std::cout << "Adding claim: "  << claim_names_.size() << std::endl;
     auto itr = claim_names_.find(cname);
     if (itr != claim_names_.end() && !overwrite) {
       return false;
@@ -327,10 +328,49 @@ public: // Exposed APIs
     return add_claim(
         cname,
         std::chrono::duration_cast<
-          std::chrono::seconds>(tp.time_since_epoch()).count()
+          std::chrono::seconds>(tp.time_since_epoch()).count(),
+        overwrite
         );
   }
 
+  /**
+   */
+  template <typename T>
+  bool add_claim(enum registered_claims cname, T&& cvalue, bool overwrite=false)
+  {
+    return add_claim(
+        reg_claims_to_str(cname),
+        std::forward<T>(cvalue),
+        overwrite
+        );
+  }
+
+  /**
+   */
+  bool add_claim(enum registered_claims cname, system_time_t tp, bool overwrite=false)
+  {
+    return add_claim(
+        reg_claims_to_str(cname),
+        std::chrono::duration_cast<
+          std::chrono::seconds>(tp.time_since_epoch()).count(),
+        overwrite
+        );
+  }
+
+  /**
+   */
+  decltype(auto) get_claim_value(const string_view cname) const
+  {
+    return payload_[cname.data()];
+  }
+
+  /**
+   */
+  decltype(auto) get_claim_value(enum registered_claims cname) const
+  {
+    return get_claim_value(reg_claims_to_str(cname));
+  }
+
   /**
    */
   bool remove_claim(const string_view cname)
@@ -346,11 +386,30 @@ public: // Exposed APIs
 
   /**
    */
-  bool has_claim(const std::string& cname) const noexcept
+  bool remove_claim(enum registered_claims cname)
   {
+    return remove_claim(reg_claims_to_str(cname));
+  }
+
+  /**
+   */
+  //TODO: Not all libc++ version agrees with this
+  //because count() is not made const for is_transparent
+  //based overload
+  bool has_claim(const string_view cname) const noexcept
+  {
+    std::cout << "CSZ: " << claim_names_.size() << std::endl;
+    for (auto c : claim_names_) std::cout << "Claim: " << c << std::endl;
     return claim_names_.count(cname);
   }
 
+  /**
+   */
+  bool has_claim(enum registered_claims cname) const noexcept
+  {
+    return has_claim(reg_claims_to_str(cname));
+  }
+
   /**
    */
   template <typename T>
@@ -451,7 +510,7 @@ public: // Exposed APIs
 
   /*!
    */
-  bool verify(const jwt_header& header,
+  verify_result_t verify(const jwt_header& header,
               const string_view hdr_pld_sign,
               const string_view jwt_sign);
 
@@ -573,10 +632,25 @@ public: // Exposed APIs
    */
   jwt_object& add_claim(const string_view name, system_time_t time_point);
 
+  /**
+   */
+  template <typename T>
+  jwt_object& add_claim(enum registered_claims cname, T&& value)
+  {
+    return add_claim(reg_claims_to_str(cname), std::forward<T>(value));
+  }
+
   /**
    */
   jwt_object& remove_claim(const string_view name);
 
+  /**
+   */
+  jwt_object& remove_claim(enum registered_claims cname)
+  {
+    return remove_claim(reg_claims_to_str(cname));
+  }
+
   /**
    */
   std::string signature() const;
diff --git a/include/jwt/test/test_jwt_object b/include/jwt/test/test_jwt_object
index ffbb701..b970955 100755
Binary files a/include/jwt/test/test_jwt_object and b/include/jwt/test/test_jwt_object differ
diff --git a/include/jwt/test/test_jwt_object.cc b/include/jwt/test/test_jwt_object.cc
index 50c1032..69deda1 100644
--- a/include/jwt/test/test_jwt_object.cc
+++ b/include/jwt/test/test_jwt_object.cc
@@ -2,6 +2,7 @@
 #include <map>
 #include <string>
 #include <chrono>
+#include <ctime>
 #include <unordered_map>
 #include "jwt/jwt.hpp"
 
@@ -74,15 +75,18 @@ MIGkAgEBBDBeLCgapjZmvTatMHaYX3A02+0Ys3Tr8kda+E9DFnmCSiCOEig519fT
      .add_claim("where", "airport")
      .add_claim("time_str", "8:18pm 24 Nov 2017")
      .add_claim("id", 1)
+     .add_claim("exp", std::chrono::system_clock::now())
      ;
 
   std::cout << "pem sign " << obj.signature() << std::endl;
+  std::cout << "Get claim value for exp: " << obj.payload().get_claim_value("exp") << std::endl;
+  sleep(4);
   auto dec_obj = jwt::decode(obj.signature(), pub_key, algorithms({"es256"}));
   std::cout << dec_obj.payload() << std::endl;
 }
 
 int main() {
-  basic_jwt_object_test();
+  //basic_jwt_object_test();
   jwt_object_pem_test();
   return 0;
 }