diff --git a/CMakeLists.txt b/CMakeLists.txt
index d5418ea..c3e250f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -32,6 +32,10 @@ if(BUILD_EXAMPLES)
     set(EXAM_HMAP hmap_example)
     add_executable(${EXAM_HMAP} examples/hmap_example.cpp)
     target_link_libraries(${EXAM_HMAP} ${PROJECT_NAME})
+
+    set(EXAM_HVEC hvec_example)
+    add_executable(${EXAM_HVEC} examples/hvec_example.cpp)
+    target_link_libraries(${EXAM_HVEC} ${PROJECT_NAME})
 endif()
 
 include(GNUInstallDirs)
diff --git a/examples/hvec_example.cpp b/examples/hvec_example.cpp
new file mode 100644
index 0000000..4ed1d59
--- /dev/null
+++ b/examples/hvec_example.cpp
@@ -0,0 +1,47 @@
+#include <print>
+#include <vector>
+
+#include <snipplib/containers/snplib_hvec.h>
+
+using namespace snplib;
+
+struct visitor {
+    using types = std::tuple<std::string, unsigned long>;
+
+    void operator()(auto& v)
+    {
+        using val_t = std::decay_t<decltype(v)>;
+
+        if constexpr (std::ranges::input_range<val_t>) {
+            std::println("range val = {}", v);
+        } else {
+            std::println("val = {}", v);
+        }
+    }
+};
+
+
+int main()
+{
+    HeterogenVec vec;
+
+    vec.push(1.1);
+    vec.push(std::string{"AAA"});
+    vec.push(100UL);
+    vec.push(200UL);
+    vec.push(300UL);
+
+    std::vector<char> v{'q', 'w', 'e'};
+
+    vec.emplace<std::string>(std::from_range_t{}, v);
+
+    vec.visit(visitor{});
+    vec.visitRange(visitor{});
+
+    vec.clear();
+
+    std::println("\n\tafter clear() ...");
+    vec.visit(visitor{});
+
+    return 0;
+}
diff --git a/include/snipplib/containers/snplib_hvec.h b/include/snipplib/containers/snplib_hvec.h
index 8211559..7c63704 100644
--- a/include/snipplib/containers/snplib_hvec.h
+++ b/include/snipplib/containers/snplib_hvec.h
@@ -15,11 +15,20 @@ namespace details
 template <typename OT, typename TT, size_t... Is>
 concept snplib_all_func_oper_c = requires(OT obj) { (obj(std::declval<std::tuple_element_t<Is, TT>&>()), ...); };
 
+template <typename OT, typename TT, size_t... Is>
+concept snplib_all_func_oper_range_c =
+    requires(OT obj) { (obj(std::declval<std::vector<std::tuple_element_t<Is, TT>>&>()), ...); };
+
 template <typename OT, typename TT>
 struct snplib_check_all_func_oper_t {
     static constexpr bool value = false;
 };
 
+template <typename OT, typename TT>
+struct snplib_check_all_func_oper_range_t {
+    static constexpr bool value = false;
+};
+
 template <typename OT, typename TT>
     requires requires { typename std::tuple_size<TT>::type; }
 struct snplib_check_all_func_oper_t<OT, TT> {
@@ -28,10 +37,21 @@ struct snplib_check_all_func_oper_t<OT, TT> {
     }(std::make_index_sequence<std::tuple_size<TT>::value>{});
 };
 
+template <typename OT, typename TT>
+    requires requires { typename std::tuple_size<TT>::type; }
+struct snplib_check_all_func_oper_range_t<OT, TT> {
+    static constexpr bool value = []<std::size_t... Is>(std::index_sequence<Is...>) {
+        return snplib_all_func_oper_range_c<OT, TT, Is...>;
+    }(std::make_index_sequence<std::tuple_size<TT>::value>{});
+};
+
 
 template <typename OT, typename TT>
 static constexpr bool snplib_check_all_func_oper_v = snplib_check_all_func_oper_t<OT, TT>::value;
 
+template <typename OT, typename TT>
+static constexpr bool snplib_check_all_func_oper_range_v = snplib_check_all_func_oper_range_t<OT, TT>::value;
+
 }  // namespace details
 
 
@@ -42,6 +62,13 @@ concept snplib_hvec_visitor_c = requires {
     requires details::snplib_check_all_func_oper_v<T, typename T::types>;
 };
 
+template <typename T>
+concept snplib_hvec_range_visitor_c = requires {
+    requires snplib_tuple_c<typename T::types>;
+
+    requires details::snplib_check_all_func_oper_range_v<T, typename T::types>;
+};
+
 
 class HeterogenVec
 {
@@ -128,7 +155,7 @@ public:
                 }
             });
 
-            _copyFunc.emplace_back([](HeterogenVec* from, HeterogenVec* to) {
+            _copyFunc.emplace_back([](const HeterogenVec* from, HeterogenVec* to) {
                 if (_values<v_t>.contains(from)) {
                     _values<v_t>[to] = _values<v_t>[from];
                 }
@@ -139,16 +166,33 @@ public:
         _values<v_t>[this].push_back(std::forward<VT>(value));
     }
 
+    template <typename VT, typename... CtorArgTs>
+    void emplace(CtorArgTs&&... args)
+    {
+        push(VT(std::forward<CtorArgTs>(args)...));
+    }
 
+    // per element visiting
     template <snplib_hvec_visitor_c VT>
     void visit(VT&& visitor)
     {
-        auto invoke_per_type = [&visitor, this]<typename T>() {
+        auto invoke_per_elem = [&visitor, this]<typename T>() {
             for (auto& elem : _values<T>[this]) {
                 visitor(elem);
             }
         };
 
+        [&invoke_per_elem]<size_t... Is>(std::index_sequence<Is...>) {
+            (invoke_per_elem.template operator()<std::tuple_element_t<Is, typename VT::types>>(), ...);
+        }(std::make_index_sequence<std::tuple_size_v<typename VT::types>>{});
+    }
+
+    // per range of type visiting
+    template <snplib_hvec_visitor_c VT>
+    void visitRange(VT&& visitor)
+    {
+        auto invoke_per_type = [&visitor, this]<typename T>() { visitor(_values<T>[this]); };
+
         [&invoke_per_type]<size_t... Is>(std::index_sequence<Is...>) {
             (invoke_per_type.template operator()<std::tuple_element_t<Is, typename VT::types>>(), ...);
         }(std::make_index_sequence<std::tuple_size_v<typename VT::types>>{});
diff --git a/include/snipplib/network/snplib_network.h b/include/snipplib/network/snplib_network.h
index ee7964f..00cbc25 100644
--- a/include/snipplib/network/snplib_network.h
+++ b/include/snipplib/network/snplib_network.h
@@ -1,6 +1,8 @@
 #pragma once
 
+#include <set>
 #include "../concepts/snplib_concepts.h"
+#include "../containers/snplib_hvec.h"
 
 namespace snplib
 {
@@ -44,9 +46,9 @@ concept snplib_net_session_c = std::derived_from<T, std::enable_shared_from_this
 
     snplib_net_connection_c<typename T::connection_t>;
 
-    { t.start(std::declval<typename T::connection_t>()) } -> snplib_async_retval_c;
+    { t.startSession(std::declval<typename T::connection_t>()) } -> snplib_async_retval_c;
 
-    t.stop();
+    t.stopSession();
 };
 
 
@@ -84,7 +86,7 @@ protected:
 };
 
 template <typename T>
-concept snplib_netserver_c = requires(T t) {
+concept snplib_netserver_c = std::derived_from<T, snplib_netserver_iface_t> && requires(T t) {
     // static constexpr member
     std::formattable<decltype(T::id), char>;
     []() { [[maybe_unused]] static constexpr auto val = T::id; }();
@@ -97,4 +99,50 @@ concept snplib_netserver_c = requires(T t) {
 
     { t.disconnectClients() } -> snplib_error_c;
 };
+
+
+
+/*                          SINGLE-PROTO*/
+
+template <snplib_net_listener_c ListenerT>
+class snplib_generic_netserver_t
+{
+public:
+    typedef std::error_code error_t;
+
+    using session_t = typename ListenerT::session_t;
+
+    snplib_generic_netserver_t(std::unique_ptr<ListenerT> listener) : _listener(std::move(listener)) {}
+
+    error_t start()
+    {
+        auto err = _listener->start();
+        if (err) {
+            return snplib_deduced_error(err, std::make_error_code(std::errc::io_error));
+        }
+
+        startListen();
+    }
+
+    error_t stop()
+    {
+        _listener->stop();
+
+        return {};
+    }
+
+protected:
+    std::unique_ptr<ListenerT> _listener{};
+    std::set<std::weak_ptr<session_t>> _sessions{};
+
+    void startListen()
+    {
+        auto sess = co_await _listener->accept();
+        if (sess) {
+            _sessions.insert(sess);
+        }
+    }
+};
+
+
 }  // namespace snplib
\ No newline at end of file