diff --git a/include/dxfeed_graal_cpp_api/api/DXFeedSubscription.hpp b/include/dxfeed_graal_cpp_api/api/DXFeedSubscription.hpp
index a8fe18b8..316ca5d3 100644
--- a/include/dxfeed_graal_cpp_api/api/DXFeedSubscription.hpp
+++ b/include/dxfeed_graal_cpp_api/api/DXFeedSubscription.hpp
@@ -75,6 +75,10 @@ class DXFeedSubscription : public std::enable_shared_from_this<DXFeedSubscriptio
 
     bool isClosedImpl() noexcept;
 
+    void addSymbolImpl(const char *symbol) noexcept;
+
+    void removeSymbolImpl(const char *symbol) noexcept;
+
   public:
     std::string toString() const { return fmt::format("DXFeedSubscription{{{}}}", handler_.toString()); }
 
@@ -194,6 +198,20 @@ class DXFeedSubscription : public std::enable_shared_from_this<DXFeedSubscriptio
         closeImpl();
     }
 
+    /**
+     * Adds listener for events.
+     * Event lister can be added only when subscription is not producing any events.
+     * The subscription must be either empty
+     * (its set of @ref ::getSymbols() "symbols" is empty or not @ref ::attach() "attached" to any feed
+     * (its set of change listeners is empty).
+     *
+     * This method does nothing if this subscription is closed.
+     *
+     * @tparam EventListener The listener type. Listener can be callable with signature: `void(const
+     * std::vector<std::shared_ptr<EventType>&)`
+     * @param listener The event listener
+     * @return The listener id
+     */
     template <typename EventListener>
     std::size_t addEventListener(EventListener &&listener) noexcept
 #if __cpp_concepts
@@ -205,31 +223,59 @@ class DXFeedSubscription : public std::enable_shared_from_this<DXFeedSubscriptio
         return onEvent_ += listener;
     }
 
+    /**
+     * Removes listener for events.
+     *
+     * @param listenerId The listener id
+     */
     void removeEventListener(std::size_t listenerId) noexcept { onEvent_ -= listenerId; }
 
+    /**
+     * Returns a reference to an incoming events' handler (delegate), to which listeners can be added and removed.
+     *
+     * @return The incoming events' handler (delegate)
+     */
     const auto &onEvent() noexcept { return onEvent_; }
 
+    template <typename Symbol> void addSymbol(Symbol &&symbol) noexcept {
+        if constexpr (isDebug) {
+            debug("{}::addSymbol(symbol = {})", toString(), symbol);
+        }
+
+        if constexpr (std::is_same_v<std::decay_t<Symbol>, std::string>) {
+            addSymbolImpl(symbol.c_str());
+        }
 #if __cpp_lib_string_view
-    void addSymbol(std::string_view symbol) noexcept;
+        else if constexpr (std::is_same_v<std::decay_t<Symbol>, std::string_view>) {
+            addSymbolImpl(symbol.data());
+        }
 #endif
+        else {
+            addSymbolImpl(symbol);
+        }
+    }
 
-    void addSymbol(const char *symbol) noexcept;
-
-    void addSymbol(const std::string &symbol) noexcept;
-
-    template <typename SymbolsCollection> void addSymbols(SymbolsCollection &&collection) noexcept;
-
-    template <typename Symbol> void addSymbols(std::initializer_list<Symbol> collection) noexcept;
-
-    template <typename Symbol> void removeSymbol(Symbol &&symbol) noexcept;
+    template <typename Symbol> void removeSymbol(Symbol &&symbol) noexcept {
+        if constexpr (isDebug) {
+            debug("{}::removeSymbol(symbol = {})", toString(), symbol);
+        }
 
+        if constexpr (std::is_same_v<std::decay_t<Symbol>, std::string>) {
+            removeSymbolImpl(symbol.c_str());
+        }
 #if __cpp_lib_string_view
-    void removeSymbol(std::string_view symbol) noexcept;
+        else if constexpr (std::is_same_v<std::decay_t<Symbol>, std::string_view>) {
+            removeSymbolImpl(symbol.data());
+        }
 #endif
+        else {
+            removeSymbolImpl(symbol);
+        }
+    }
 
-    void removeSymbol(const char *symbol) noexcept;
+    template <typename SymbolsCollection> void addSymbols(SymbolsCollection &&collection) noexcept;
 
-    void removeSymbol(const std::string &symbol) noexcept;
+    template <typename Symbol> void addSymbols(std::initializer_list<Symbol> collection) noexcept;
 
     template <typename SymbolsCollection> void removeSymbols(SymbolsCollection &&collection) noexcept;
 
diff --git a/include/dxfeed_graal_cpp_api/internal/Isolate.hpp b/include/dxfeed_graal_cpp_api/internal/Isolate.hpp
index 39fbd89b..9671d777 100644
--- a/include/dxfeed_graal_cpp_api/internal/Isolate.hpp
+++ b/include/dxfeed_graal_cpp_api/internal/Isolate.hpp
@@ -249,7 +249,9 @@ class Isolate final {
     }
 
     template <typename F, typename R>
+#if __cpp_concepts
         requires std::convertible_to<R, std::invoke_result_t<F &&, GraalIsolateThreadHandle>>
+#endif
     auto runIsolatedOrElse(F &&f, R defaultValue) {
         return std::visit(
             [defaultValue =
@@ -280,7 +282,9 @@ class Isolate final {
 template <typename F> auto runIsolated(F &&f) { return Isolate::getInstance()->runIsolated(std::forward<F>(f)); }
 
 template <typename F, typename R>
+#if __cpp_concepts
     requires std::convertible_to<R, std::invoke_result_t<F &&, GraalIsolateThreadHandle>>
+#endif
 auto runIsolatedOrElse(F &&f, R defaultValue) {
     return Isolate::getInstance()->runIsolatedOrElse(std::forward<F>(f), std::move(defaultValue));
 }
diff --git a/samples/cpp/PrintQuoteEvents/src/main.cpp b/samples/cpp/PrintQuoteEvents/src/main.cpp
index 0abc29ea..77cb5f69 100644
--- a/samples/cpp/PrintQuoteEvents/src/main.cpp
+++ b/samples/cpp/PrintQuoteEvents/src/main.cpp
@@ -21,6 +21,11 @@ auto cApiStateToString(dxfc_dxendpoint_state_t state) {
     return "";
 }
 
+#if !defined(__PRETTY_FUNCTION__) && !defined(__GNUC__)
+#define __PRETTY_FUNCTION__ __FUNCSIG__
+#endif
+
+
 int main() {
     {
         using namespace std::string_literals;
diff --git a/src/api/DXFeedSubscription.cpp b/src/api/DXFeedSubscription.cpp
index 6a4dff0f..f542c0f6 100644
--- a/src/api/DXFeedSubscription.cpp
+++ b/src/api/DXFeedSubscription.cpp
@@ -6,6 +6,7 @@
 #include <dxfeed_graal_cpp_api/api.hpp>
 
 #include <memory>
+#include <typeinfo>
 
 namespace dxfcpp {
 
@@ -25,27 +26,13 @@ void DXFeedSubscription::detach(std::shared_ptr<DXFeed> feed) noexcept {
     feed->detachSubscription(shared_from_this());
 }
 
-#if __cpp_lib_string_view
-void DXFeedSubscription::addSymbol(std::string_view symbol) noexcept {
+template <typename Symbol> auto symbolDataRetriever(Symbol &&s) {
     if constexpr (isDebug) {
-        debug("{}::addSymbol(symbol = {})", toString(), symbol);
+        debug("{}", typeid(decltype(s)).name());
     }
-
-    runIsolatedOrElse(
-        [handler = bit_cast<dxfg_subscription_t *>(handler_.get()), symbol](auto threadHandle) {
-            dxfg_string_symbol_t s{{STRING}, symbol.data()};
-
-            return dxfg_DXFeedSubscription_addSymbol(threadHandle, handler, (dxfg_symbol_t *)&s) == 0;
-        },
-        false);
 }
-#endif
-
-void DXFeedSubscription::addSymbol(const char *symbol) noexcept {
-    if constexpr (isDebug) {
-        debug("{}::addSymbol(symbol = {})", toString(), symbol);
-    }
 
+void DXFeedSubscription::addSymbolImpl(const char *symbol) noexcept {
     runIsolatedOrElse(
         [handler = bit_cast<dxfg_subscription_t *>(handler_.get()), symbol](auto threadHandle) {
             dxfg_string_symbol_t s{{STRING}, symbol};
@@ -55,41 +42,7 @@ void DXFeedSubscription::addSymbol(const char *symbol) noexcept {
         false);
 }
 
-void DXFeedSubscription::addSymbol(const std::string &symbol) noexcept {
-    if constexpr (isDebug) {
-        debug("{}::addSymbol(symbol = {})", toString(), symbol);
-    }
-
-    runIsolatedOrElse(
-        [handler = bit_cast<dxfg_subscription_t *>(handler_.get()), symbol](auto threadHandle) {
-            dxfg_string_symbol_t s{{STRING}, symbol.c_str()};
-
-            return dxfg_DXFeedSubscription_addSymbol(threadHandle, handler, (dxfg_symbol_t *)&s) == 0;
-        },
-        false);
-}
-
-#if __cpp_lib_string_view
-void DXFeedSubscription::removeSymbol(std::string_view symbol) noexcept {
-    if constexpr (isDebug) {
-        debug("{}::removeSymbol(symbol = {})", toString(), symbol);
-    }
-
-    runIsolatedOrElse(
-        [handler = bit_cast<dxfg_subscription_t *>(handler_.get()), symbol](auto threadHandle) {
-            dxfg_string_symbol_t s{{STRING}, symbol.data()};
-
-            return dxfg_DXFeedSubscription_removeSymbol(threadHandle, handler, (dxfg_symbol_t *)&s) == 0;
-        },
-        false);
-}
-#endif
-
-void DXFeedSubscription::removeSymbol(const char *symbol) noexcept {
-    if constexpr (isDebug) {
-        debug("{}::removeSymbol(symbol = {})", toString(), symbol);
-    }
-
+void DXFeedSubscription::removeSymbolImpl(const char *symbol) noexcept {
     runIsolatedOrElse(
         [handler = bit_cast<dxfg_subscription_t *>(handler_.get()), symbol](auto threadHandle) {
             dxfg_string_symbol_t s{{STRING}, symbol};
@@ -99,20 +52,6 @@ void DXFeedSubscription::removeSymbol(const char *symbol) noexcept {
         false);
 }
 
-void DXFeedSubscription::removeSymbol(const std::string &symbol) noexcept {
-    if constexpr (isDebug) {
-        debug("{}::removeSymbol(symbol = {})", toString(), symbol);
-    }
-
-    runIsolatedOrElse(
-        [handler = bit_cast<dxfg_subscription_t *>(handler_.get()), symbol](auto threadHandle) {
-            dxfg_string_symbol_t s{{STRING}, symbol.c_str()};
-
-            return dxfg_DXFeedSubscription_removeSymbol(threadHandle, handler, (dxfg_symbol_t *)&s) == 0;
-        },
-        false);
-}
-
 void DXFeedSubscription::closeImpl() noexcept {
     if (!handler_) {
         return;