diff --git a/.jules/bolt.md b/.jules/bolt.md
index 9e4d903..c82a56b 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -8,3 +8,7 @@
 ## 2024-05-11 - [XML Lookup Optimization]
 **Learning:** Repeatedly calling `pugi::xml_node::find_child_by_attribute` to look up prayer times by `dayofyear` is an O(N) linear search bottleneck that slows down `zaman` class instantiations.
 **Action:** Replaced it with an O(1) array lookup. Since `dayofyear` acts as a sequential 0-based index (0-365), we can cache the `const char*` text of each `prayertimes` node into a static `cached_nodes[400]` array using a magic static block. This reduced instantiation time nearly by half.
+
+## 2026-05-16 - [Optimize String Formatting via Stack Buffer]
+**Learning:** In heavily called string formatting functions like `td_to_vakt`, multiple `std::to_string` allocations and string concatenations (`+`) cause severe memory allocation bottlenecks.
+**Action:** Using a manual, fixed-size stack character buffer (e.g., `char buf[6]`) and direct ASCII arithmetic (`'0' + value`) avoids temporary object creation and yields a significant performance improvement.
diff --git a/run_tests b/run_tests
deleted file mode 100755
index 6d4062d..0000000
Binary files a/run_tests and /dev/null differ
diff --git a/src/src-class/Zaman.cpp b/src/src-class/Zaman.cpp
index d65d370..dd1bab8 100644
--- a/src/src-class/Zaman.cpp
+++ b/src/src-class/Zaman.cpp
@@ -70,7 +70,25 @@ unsigned int zaman::vakt_to_td(const std::string& vakt)
 
 std::string zaman::td_to_vakt(unsigned int td)
 {
-	return std::to_string(int(td / 60) % 12) + ":" + std::to_string(int(td % 60));
+	// ⚡ Bolt Optimizasyonu: std::to_string ve std::string birleştirme tahsisatlarını manuel karakter arabelleği ile engelle
+	int h = int(td / 60) % 12;
+	int m = int(td % 60);
+	char buf[6];
+	int i = 0;
+	if (h >= 10) {
+		buf[i++] = '0' + (h / 10);
+		buf[i++] = '0' + (h % 10);
+	} else {
+		buf[i++] = '0' + h;
+	}
+	buf[i++] = ':';
+	if (m >= 10) {
+		buf[i++] = '0' + (m / 10);
+		buf[i++] = '0' + (m % 10);
+	} else {
+		buf[i++] = '0' + m;
+	}
+	return std::string(buf, i);
 }
 
 void zaman::vkt_h_v_d()
@@ -89,36 +107,19 @@ void zaman::vkt_h_v_d()
 
 	char buffer[5];
 
-	static const pugi::xml_node* cached_nodes = []() {
-		static pugi::xml_document doc;
-		if (!doc.load_file("include/XML/Vakitler.xml") && !doc.load_file("vakitler.xml")) {
-			throw std::runtime_error("XML load failed");
-		}
-		pugi::xml_node node = doc.child("cityinfo");
-		if (!node) {
-			throw std::runtime_error("Missing cityinfo node");
-		}
-
-		// ⚡ Bolt Optimizasyonu: XML düğümlerini 'dayofyear' özniteliğine göre önbelleğe alarak O(1) erişim sağla (O(N) doğrusal arama yerine)
-		// Her nesne örneği oluşturulduğunda O(N) doğrusal arama darboğazını ortadan kaldırır
-		static pugi::xml_node nodes[400];
-		for (pugi::xml_node pt = node.child("prayertimes"); pt; pt = pt.next_sibling("prayertimes")) {
+	// ⚡ Bolt Optimizasyonu: XML düğümlerini 'dayofyear' özniteliğine göre önbelleğe alarak O(1) erişim sağla (O(N) doğrusal arama yerine)
+	// Her nesne örneği oluşturulduğunda O(N) doğrusal arama darboğazını ortadan kaldırır
+	static const char** cached_nodes_ptr = []() {
+		static const char* nodes[400] = {nullptr};
+		for (pugi::xml_node pt = zaman::sehir.child("prayertimes"); pt; pt = pt.next_sibling("prayertimes")) {
 			int day = pt.attribute("dayofyear").as_int(-1);
 			if (day >= 0 && day < 400) {
-				nodes[day] = pt;
+				nodes[day] = pt.text().get();
 			}
 		}
 		return nodes;
 	}();
-
-	static const char* cached_nodes[400] = {nullptr};
-	static bool cached_nodes_init = []() {
-		for (pugi::xml_node pt = cached_sehir.child("prayertimes"); pt; pt = pt.next_sibling("prayertimes")) {
-			int day = std::atoi(pt.attribute("dayofyear").value());
-			if (day >= 0 && day < 400) cached_nodes[day] = pt.text().get();
-		}
-		return true;
-	}();
+	const char* const* cached_nodes = cached_nodes_ptr;
 
 	zaman::xml_bu_gun = (zaman::h_rakam_gun_senenin >= 0 && zaman::h_rakam_gun_senenin < 400 && cached_nodes[zaman::h_rakam_gun_senenin]) ? cached_nodes[zaman::h_rakam_gun_senenin] : "";