diff --git a/Core/Src/main.c b/Core/Src/main.c
index ed1037d..f8e0a4c 100644
--- a/Core/Src/main.c
+++ b/Core/Src/main.c
@@ -47,7 +47,7 @@ typedef enum {
 #define STDERR_FILENO 2
 
 #define BOOTLOADER_RCC_CSR_ENTRY_MASK (RCC_CSR_WWDGRSTF | RCC_CSR_IWDGRSTF | RCC_CSR_SFTRSTF | RCC_CSR_PINRSTF)
-#define BOOTLOADER_SIZE (20 * 1024)
+#define BOOTLOADER_SIZE 0x4C00
 #define USER_PROGRAM (FLASH_BASE + BOOTLOADER_SIZE)
 /* USER CODE END PD */
 
@@ -127,95 +127,6 @@ void start_user_program() {
 
 uint8_t ack[] = {0x01};
 uint8_t nack[] = {0xFE};
-void receive() {
-	UpdateTarget target;
-
-	HAL_UART_Receive(&huart1, &target, 1, 1000);
-	HAL_UART_Transmit(&huart1, ack, sizeof(ack), HAL_MAX_DELAY);
-
-	uint8_t length_buffer[2];
-	HAL_UART_Receive(&huart1, length_buffer, sizeof(length_buffer), HAL_MAX_DELAY);
-	HAL_UART_Transmit(&huart1, length_buffer, sizeof(length_buffer), HAL_MAX_DELAY);
-	uint16_t length = length_buffer[0] + (length_buffer[1] << 8);
-
-	uint8_t* data = malloc(length);
-	HAL_UART_Receive(&huart1, data, length, 1000);
-
-	// Calculate the CRC of the data and send it back
-	// @todo Figure how we can actually use the hardware crc
-	/* uint32_t crc = HAL_CRC_Calculate(&hcrc, (uint32_t*)data, length); */
-	uint32_t crc = crc32(data, length);
-	uint8_t c[] = {crc, crc >> 8, crc >> 16, crc >> 24};
-	HAL_UART_Transmit(&huart1, c, sizeof(c), HAL_MAX_DELAY);
-
-	switch (target) {
-		case TARGET_I2C: {
-			 // Unlock flash
-			 HAL_FLASH_Unlock();
-			 HAL_UART_Transmit(&huart1, ack, sizeof(ack), HAL_MAX_DELAY);
-
-			 // Erase flash
-			 uint32_t error = 0;
-			 FLASH_EraseInitTypeDef erase = {
-				 .TypeErase = FLASH_TYPEERASE_PAGES,
-				 .PageAddress = (uint32_t)0x8005000,
-				 .NbPages = ceil(length/1024.0f),
-			 };
-			 HAL_FLASHEx_Erase(&erase, &error);
-
-			 // Write to flash
-			 for (int i = 0; i < length/2; ++i) {
-				 if (HAL_FLASH_Program(FLASH_TYPEPROGRAM_HALFWORD, 0x8005000 + i*2, ((uint16_t*)data)[i])) {
-					 return;
-				 }
-				 uint8_t progress[] = {(i*2) & 0xFF, (i*2) >> 8};
-				 HAL_UART_Transmit(&huart1, progress, sizeof(progress), HAL_MAX_DELAY);
-			 }
-			 uint8_t progress[] = {(length) & 0xFF, (length) >> 8};
-			 HAL_UART_Transmit(&huart1, progress, sizeof(progress), HAL_MAX_DELAY);
-
-			 // Done
-			 HAL_FLASH_Lock();
-			 HAL_UART_Transmit(&huart1, ack, sizeof(ack), HAL_MAX_DELAY);
-
-			 should_start_user_program = 1;
-
-			 break;
-		 }
-
-		default:
-			 printf("Target not implemented!\n\r");
-			 break;
-
-	}
-}
-
-uint8_t byte;
-void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart) {
-	if (huart->Instance == USART1) {
-		static uint8_t command_mode = 0;
-
-		if (command_mode) {
-			switch (byte) {
-				// Upload firmware
-				case 'u':
-					HAL_UART_Transmit(&huart1, ack, sizeof(ack), HAL_MAX_DELAY);
-					receive();
-					break;
-
-				default:
-					HAL_UART_Transmit(&huart1, nack, sizeof(nack), HAL_MAX_DELAY);
-					break;
-			}
-			command_mode = 0;
-		} else if (byte == 0xFF) {
-			command_mode = 1;
-			HAL_UART_Transmit(&huart1, ack, sizeof(ack), HAL_MAX_DELAY);
-		}
-
-		HAL_UART_Receive_IT(&huart1, &byte, 1);
-	}
-}
 
 uint8_t i2c_data;
 void HAL_I2C_SlaveRxCpltCallback(I2C_HandleTypeDef *hi2c) {
@@ -266,14 +177,14 @@ void HAL_I2C_SlaveRxCpltCallback(I2C_HandleTypeDef *hi2c) {
 				uint32_t error = 0;
 				FLASH_EraseInitTypeDef erase = {
 					.TypeErase = FLASH_TYPEERASE_PAGES,
-					.PageAddress = (uint32_t)0x8005000,
+					.PageAddress = (uint32_t)USER_PROGRAM,
 					.NbPages = ceil(length/1024.0f),
 				};
 				HAL_FLASHEx_Erase(&erase, &error);
 
 				// Write to flash
 				for (int i = 0; i < length/2; ++i) {
-					if (HAL_FLASH_Program(FLASH_TYPEPROGRAM_HALFWORD, 0x8005000 + i*2, ((uint16_t*)data)[i])) {
+					if (HAL_FLASH_Program(FLASH_TYPEPROGRAM_HALFWORD, USER_PROGRAM + i*2, ((uint16_t*)data)[i])) {
 						break;
 					}
 				}
@@ -452,7 +363,6 @@ int main(void)
 	}
 
 	printf("\tAwaiting command\n\r");
-	HAL_UART_Receive_IT(&huart1, &byte, 1);
 	HAL_I2C_Slave_Receive_IT(&hi2c1, &i2c_data, 1);
 
 	// Run the bootloader
diff --git a/Makefile b/Makefile
index 6958ab4..02eb4f4 100644
--- a/Makefile
+++ b/Makefile
@@ -20,7 +20,7 @@ TARGET = bootloader
 # building variables
 ######################################
 # debug build?
-DEBUG = 1
+DEBUG = 0
 # optimization
 OPT = -Os