diff --git a/Makefile b/Makefile
index 7857110..18a14e7 100644
--- a/Makefile
+++ b/Makefile
@@ -2,21 +2,25 @@
 
 CC = g++
 CFLAGS_DEFAULT = -march=native -std=c++23
-CFLAGS_DEBUG   = -Wall -Werror -Wno-uninitialized -O0 -fanalyzer -ggdb -fsanitize=address -fsanitize=undefined -fno-sanitize-recover=all -fsanitize=float-divide-by-zero -fsanitize=float-cast-overflow -fno-sanitize=null -fno-sanitize=alignment
-CFLAGS_RELEASE = -static-libgcc -static-libstdc++ -static -Ofast -fdevirtualize-speculatively -fdata-sections -ffunction-sections -Wl,-gc-sections -Wl,-strip-all -Wl,-strip-discarded -flto -s -D_FORTIFY_SOURCE=2
+CFLAGS_DEBUG   = -Wall -Werror -Wno-uninitialized -Wno-analyzer-use-of-uninitialized-value -fanalyzer -ggdb
+CFLAGS_DEBUG_S = -O0 -fsanitize=address -fsanitize=undefined -fno-sanitize-recover=all -fsanitize=float-divide-by-zero -fsanitize=float-cast-overflow
+CFLAGS_DEBUG_F = -O1 -D_FORTIFY_SOURCE=3
+CFLAGS_RELEASE = -static-libgcc -static-libstdc++ -static -Ofast -fdevirtualize-speculatively -fdata-sections -ffunction-sections -Wl,-gc-sections -Wl,-strip-all -Wl,-strip-discarded -flto -s -D_FORTIFY_SOURCE=3
 
 SOURCES = src/stadium.hpp src/stadium.cpp src/kldr.hpp
 SOURCES_TEST = src/test.cpp
 #LINKED_LIBS = -l
 OUTPUT_LIB = libstadium.so
-OUTPUT_TEST_BIN = libstadiumtest
+OUTPUT_TEST_BIN_S = libstadiumtest_sanitizer
+OUTPUT_TEST_BIN_F = libstadiumtest_fortified
 
 
 default: clean release_test
 
 
 debug_test: $(SOURCES) $(SOURCES_TEST)
-	$(CC) $(CFLAGS_DEFAULT) $(CFLAGS_DEBUG) $(SOURCES) $(SOURCES_TEST) -o $(OUTPUT_TEST_BIN)
+	$(CC) $(CFLAGS_DEFAULT) $(CFLAGS_DEBUG) $(CFLAGS_DEBUG_S) $(SOURCES) $(SOURCES_TEST) -o $(OUTPUT_TEST_BIN_S)
+	$(CC) $(CFLAGS_DEFAULT) $(CFLAGS_DEBUG) $(CFLAGS_DEBUG_F) $(SOURCES) $(SOURCES_TEST) -o $(OUTPUT_TEST_BIN_F)
 	#$(LINKED_LIBS)
 
 debug: $(SOURCES)
@@ -30,5 +34,4 @@ release: $(SOURCES)
 
 
 clean:
-	rm -f $(OUTPUT_LIB)
-	rm -f $(OUTPUT_TEST_BIN)
\ No newline at end of file
+	rm -f $(OUTPUT_LIB) $(OUTPUT_TEST_BIN_S) $(OUTPUT_TEST_BIN_F)
\ No newline at end of file
diff --git a/libstadiumtest b/libstadiumtest
deleted file mode 100755
index 2361656..0000000
Binary files a/libstadiumtest and /dev/null differ
diff --git a/src/kldr.hpp b/src/kldr.hpp
index 921aaa6..2dd0242 100644
--- a/src/kldr.hpp
+++ b/src/kldr.hpp
@@ -166,22 +166,20 @@ class KLDRArray {
 			return false;
 		}
 
-		// Add new cell to array, fast version without keys check
+		// Add new cell to array, fast version without key checks
 		void AddF (KeyT key, LengthT length, void* data) {
 			this->Keys.push_back(key);
 			this->Lengths.push_back(length);
 			void* newData = operator new(length); // Yes, allocating memory for void pointer really looks like this
-			std::copy((uint8_t*)data, (uint8_t*)data + length, (uint8_t*)newData); // Dirty hacks, YES!
+			std::copy((char*)data, (char*)data + length, (char*)newData); // Dirty hacks, YES!
 			this->Values.push_back(newData);
 			// NOTICE: there is `std::is_pod<SomeType>()`, so may be we can use one more template to make this a little more safe (may be)
 		}
 
+		// Add new cell to array, but only if key is unique
 		void Add (KeyT key, LengthT length, void* data) {
-			for (size_t i = 0; i < this->CellsAmount(); i++) {
-				if (this->Keys[i] == key) {
+			if (this->KeyExists(key))
 					throw std::invalid_argument("supplied key already exist");
-				}
-			}
 			this->AddF(key, length, data);
 		}