diff --git a/Include/Fledasty/Strings/UTF8String.h b/Include/Fledasty/Strings/UTF8String.h
index 797385e..7d3d077 100644
--- a/Include/Fledasty/Strings/UTF8String.h
+++ b/Include/Fledasty/Strings/UTF8String.h
@@ -37,6 +37,8 @@ typedef struct {
 FledastyError fledasty_utf8_string_initialize(FledastyUtf8String *new_string, unsigned char *character_string, size_t character_string_length);
 FledastyError fledasty_utf8_string_destroy(FledastyUtf8String *current_string);
 
+FledastyError fledasty_utf8_string_append(FledastyUtf8String *current_string, unsigned char *character_string, size_t character_string_length);
+
 FledastyUtf8String fledasty_utf8_string_encode(uint32_t *unicode, const size_t size);
 uint32_t *fledasty_utf8_string_decode(FledastyUtf8String *current_string, size_t *unicode_string_length);
 
diff --git a/Src/Strings/UTF8String.c b/Src/Strings/UTF8String.c
index 2a7bec6..f2aa758 100644
--- a/Src/Strings/UTF8String.c
+++ b/Src/Strings/UTF8String.c
@@ -24,6 +24,7 @@
  * -----------------------------------------------------------------------------
  */
 #include "../../Include/Fledasty/Strings/UTF8String.h"
+#include "Fledasty/Utils/Error.h"
 
 #include <Hallocy/Core/Allocator.h>
 #include <Hallocy/Core/Memory.h>
@@ -39,7 +40,7 @@ FledastyError fledasty_utf8_string_initialize(FledastyUtf8String *new_string, un
         new_string->size = 0;
         new_string->capacity = 10;
 
-        new_string->character_string = hallocy_malloc(new_string->capacity);
+        new_string->character_string = (unsigned char*)hallocy_malloc(new_string->capacity);
     } else {
         if (!fledasty_utf8_string_validate(character_string, character_string_length)) {
             return FLEDASTY_ERROR_INVALID_VALUE;
@@ -48,7 +49,7 @@ FledastyError fledasty_utf8_string_initialize(FledastyUtf8String *new_string, un
         new_string->size = character_string_length;
         new_string->capacity = new_string->size + new_string->size;
 
-        new_string->character_string = hallocy_malloc(new_string->capacity);
+        new_string->character_string = (unsigned char*)hallocy_malloc(new_string->capacity);
         for (size_t index = 0; index < new_string->size; index += 1) {
             new_string->character_string[index] = character_string[index];
         }
@@ -72,6 +73,24 @@ FledastyError fledasty_utf8_string_destroy(FledastyUtf8String *current_string) {
     return FLEDASTY_ERROR_NONE;
 }
 
+FledastyError fledasty_utf8_string_append(FledastyUtf8String *current_string, unsigned char *character_string, size_t character_string_length) {
+    if (current_string == NULL || character_string == NULL || character_string_length == 0) {
+        return FLEDASTY_ERROR_INVALID_POINTER;
+    }
+
+    if (current_string->capacity <= current_string->size + character_string_length) {
+        current_string->capacity += current_string->capacity;
+        current_string->character_string = (unsigned char*)hallocy_realloc(current_string->character_string, current_string->capacity * sizeof(unsigned char));
+    }
+
+    hallocy_copy_memory(current_string->character_string + (current_string->size - 1), character_string, character_string_length);
+
+    current_string->size += character_string_length;
+    current_string->character_string[current_string->size] = '\0';
+
+    return FLEDASTY_ERROR_NONE;
+}
+
 FledastyUtf8String fledasty_utf8_string_encode(uint32_t *unicode, const size_t size) {
     FledastyUtf8String utf8_string;
     fledasty_utf8_string_initialize(&utf8_string, NULL, 0);
@@ -85,7 +104,7 @@ FledastyUtf8String fledasty_utf8_string_encode(uint32_t *unicode, const size_t s
         if (unicode[index] <= 0x00007F) {
             if (utf8_string.capacity <= string_index) {
                 utf8_string.capacity += utf8_string.capacity;
-                utf8_string.character_string = hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
+                utf8_string.character_string = (unsigned char*)hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
             }
 
             utf8_string.character_string[string_index] = unicode[index];
@@ -93,7 +112,7 @@ FledastyUtf8String fledasty_utf8_string_encode(uint32_t *unicode, const size_t s
         } else if (unicode[index] <= 0x0007FF) {          
             if (utf8_string.capacity <= string_index + 2) {
                 utf8_string.capacity += utf8_string.capacity;
-                utf8_string.character_string = hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
+                utf8_string.character_string = (unsigned char*)hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
             }
 
             utf8_string.character_string[string_index] = 0xC0 | ((unicode[index] >> 6) & 0x07);
@@ -102,7 +121,7 @@ FledastyUtf8String fledasty_utf8_string_encode(uint32_t *unicode, const size_t s
         } else if (unicode[index] <= 0x00FFFF) {
             if (utf8_string.capacity <= string_index + 3) {
                 utf8_string.capacity += utf8_string.capacity;
-                utf8_string.character_string = hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
+                utf8_string.character_string = (unsigned char*)hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
             }
 
             utf8_string.character_string[string_index] = 0xE0 | ((unicode[index] >> 12) & 0x07);
@@ -112,7 +131,7 @@ FledastyUtf8String fledasty_utf8_string_encode(uint32_t *unicode, const size_t s
         } else if (unicode[index] <= 0x10FFFF) {
             if (utf8_string.capacity <= string_index + 4) {
                 utf8_string.capacity += utf8_string.capacity;
-                utf8_string.character_string = hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
+                utf8_string.character_string = (unsigned char*)hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
             }
 
             utf8_string.character_string[string_index] = 0xF0 | ((unicode[index] >> 18) & 0x07);
@@ -126,7 +145,7 @@ FledastyUtf8String fledasty_utf8_string_encode(uint32_t *unicode, const size_t s
     utf8_string.size = string_index;
     if (utf8_string.capacity <= utf8_string.size + 1) {
         utf8_string.capacity += utf8_string.capacity;
-        utf8_string.character_string = hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
+        utf8_string.character_string = (unsigned char*)hallocy_realloc(utf8_string.character_string, utf8_string.capacity);
     }
 
     utf8_string.character_string[utf8_string.size] = '\0';
@@ -140,7 +159,7 @@ uint32_t *fledasty_utf8_string_decode(FledastyUtf8String *current_string, size_t
 
     (*unicode_string_length) = 0;
     size_t index = 0;
-    uint32_t *unicode_string = hallocy_malloc(current_string->size * sizeof(uint32_t));
+    uint32_t *unicode_string = (uint32_t*)hallocy_malloc(current_string->size * sizeof(uint32_t));
     while (index < current_string->size) {
         if ((current_string->character_string[index] & 0xF0) == 0xF0) {
             unicode_string[*unicode_string_length] = ((current_string->character_string[index] & 0x07) << 18) | ((current_string->character_string[index + 1] & 0x3F) << 12) | ((current_string->character_string[index + 2] & 0x3F) << 6) | (current_string->character_string[index + 3] & 0x3F);
diff --git a/Tests/Main.c b/Tests/Main.c
index 0c7a3e6..35a54a9 100644
--- a/Tests/Main.c
+++ b/Tests/Main.c
@@ -229,6 +229,9 @@ int main() {
     printf("%s\n", test_string);
     printf("%s\n", test_utf8_string.character_string);
 
+    fledasty_utf8_string_append(&test_utf8_string, (unsigned char*)"😀", 4);
+    printf("%s\n", test_utf8_string.character_string);
+
     size_t unicode_length = 0;
     uint32_t *unicode = fledasty_utf8_string_decode(&test_utf8_string, &unicode_length);
     FledastyUtf8String encoded_string = fledasty_utf8_string_encode(unicode, unicode_length);