diff --git a/examples/nxp/rt1020-make-baremetal/Makefile b/examples/nxp/rt1020-evk-make-baremetal-builtin/Makefile
similarity index 62%
rename from examples/nxp/rt1020-make-baremetal/Makefile
rename to examples/nxp/rt1020-evk-make-baremetal-builtin/Makefile
index 1b5533fe32..3807cff296 100644
--- a/examples/nxp/rt1020-make-baremetal/Makefile
+++ b/examples/nxp/rt1020-evk-make-baremetal-builtin/Makefile
@@ -2,22 +2,22 @@ CFLAGS  = -W -Wall -Wextra -Werror -Wundef -Wshadow -Wdouble-promotion
 CFLAGS += -Wformat-truncation -fno-common -Wconversion -Wno-sign-conversion
 CFLAGS += -g3 -Os -ffunction-sections -fdata-sections
 CFLAGS += -I. -Icmsis_core/CMSIS/Core/Include -Icmsis_mcu/devices/MIMXRT1021 #-DCPU_MIMXRT1021DAG5A
-CFLAGS += -mcpu=cortex-m7 -mthumb -mfloat-abi=hard -mfpu=fpv5-sp-d16
-LDFLAGS ?= -Tlink.ld -nostdlib -nostartfiles --specs nano.specs -lc -lgcc -Wl,--gc-sections -Wl,-Map=$@.map
-# cmsis_mcu/devices/MIMXRT1021/gcc/MIMXRT1021xxxxx_ram.ld
-# cmsis_mcu/devices/MIMXRT1021/system_MIMXRT1021.c
+CFLAGS += -mcpu=cortex-m7 -mthumb -mfloat-abi=hard -mfpu=fpv5-d16
+LDFLAGS ?= -Tlink_ram.ld -nostdlib -nostartfiles --specs nano.specs -lc -lgcc -Wl,--gc-sections -Wl,-Map=$@.map 
 
 SOURCES = main.c syscalls.c sysinit.c
 SOURCES += cmsis_mcu/devices/MIMXRT1021/gcc/startup_MIMXRT1021.S
+CFLAGS += -D__ATOLLIC__ -D__STARTUP_CLEAR_BSS	# Make startup code work as expected
 
 # Mongoose-specific. See https://mongoose.ws/documentation/#build-options
-SOURCES += mongoose.c
+SOURCES += mongoose.c #net.c packed_fs.c
 CFLAGS += -DMG_ENABLE_TCPIP=1 -DMG_ARCH=MG_ARCH_NEWLIB -DMG_ENABLE_CUSTOM_MILLIS=1
-CFLAGS += -DMG_ENABLE_CUSTOM_RANDOM=1 #-DMG_ENABLE_PACKED_FS=1
+CFLAGS += -DMG_ENABLE_CUSTOM_RANDOM=1 -DMG_ENABLE_PACKED_FS=1 -DMG_ENABLE_DRIVER_IMXRT1020=1
+
 CFLAGS += $(CFLAGS_EXTRA)
 
 # Example specific build options. See README.md
-#CFLAGS += -DHTTP_URL=\"http://0.0.0.0/\" -DHTTPS_URL=\"https://0.0.0.0/\"
+CFLAGS += -DHTTP_URL=\"http://0.0.0.0/\" -DHTTPS_URL=\"https://0.0.0.0/\"
 
 ifeq ($(OS),Windows_NT)
   RM = cmd /C del /Q /F /S
@@ -32,6 +32,7 @@ firmware.bin: firmware.elf
 
 firmware.elf: cmsis_core cmsis_mcu $(SOURCES) hal.h link.ld Makefile
 	arm-none-eabi-gcc $(SOURCES) $(CFLAGS) $(LDFLAGS) -o $@
+	arm-none-eabi-size $@
 
 flash: firmware.bin
 	st-flash --reset write $< 0x8000000
@@ -56,8 +57,16 @@ endif
 DEVICE_URL ?= https://dash.vcon.io/api/v3/devices/4
 update: firmware.bin
 	curl --fail-with-body -su :$(VCON_API_KEY) $(DEVICE_URL)/ota --data-binary @$<
+	curl -su :$(VCON_API_KEY) https://dash.vcon.io/api/v3/devices/4/rpc/swd.exec -d '{"req":"init"}'
+	curl -su :$(VCON_API_KEY) https://dash.vcon.io/api/v3/devices/4/rpc/swd.exec -d '{"req":"wm,e000edf0,a05f0003 wm,e000edfc,1 wm,e000ed0c,5fa0004"}'
+	curl -su :$(VCON_API_KEY) https://dash.vcon.io/api/v3/devices/4/rpc/swd.exec -d '{"req":"init"}'
+	PC=`curl -su :$(VCON_API_KEY) $(DEVICE_URL)/rpc/swd.exec -d '{"req":"rm,4"}' | jq -r .resp[5:]` && \
+	SP=`curl -su :$(VCON_API_KEY) $(DEVICE_URL)/rpc/swd.exec -d '{"req":"rm,0"}' | jq -r .resp[5:]` && \
+	REQ="wm,e000ed08,0 wr,d,$$SP wr,f,$$PC" && \
+	curl -su :$(VCON_API_KEY) $(DEVICE_URL)/rpc/swd.exec -d '{"req":"'"$$REQ"'"}'
+	curl -su :$(VCON_API_KEY) $(DEVICE_URL)/rpc/swd.exec -d '{"req":"wm,e000edf0,a05f0001"}'
 
-test update: CFLAGS += -DUART_DEBUG=USART1
+test update: CFLAGS += -DUART_DEBUG=LPUART2
 test: update
 	curl --fail-with-body -su :$(VCON_API_KEY) $(DEVICE_URL)/tx?t=5 | tee /tmp/output.txt
 	grep 'READY, IP:' /tmp/output.txt       # Check for network init
diff --git a/examples/nxp/rt1020-evk-make-baremetal-builtin/hal.h b/examples/nxp/rt1020-evk-make-baremetal-builtin/hal.h
new file mode 100644
index 0000000000..eb9dffa5e3
--- /dev/null
+++ b/examples/nxp/rt1020-evk-make-baremetal-builtin/hal.h
@@ -0,0 +1,288 @@
+// Copyright (c) 2023 Cesanta Software Limited
+// All rights reserved
+// https://www.nxp.com/webapp/Download?colCode=IMXRT1020RM
+// https://cache.nxp.com/secured/assets/documents/en/user-guide/MIMXRT1020EVKHUG.pdf
+
+#pragma once
+
+#include "MIMXRT1021.h"
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+
+#define BIT(x) (1UL << (x))
+#define SETBITS(R, CLEARMASK, SETMASK) (R) = ((R) & ~(CLEARMASK)) | (SETMASK)
+#define PIN(bank, num) ((((bank) - '0') << 8) | (num))
+#define PINNO(pin) (pin & 255)
+#define PINBANK(pin) (pin >> 8)
+
+// Use LED for blinking, GPIO_AD_B0_05. GPIO1.5 (schematics)
+#define LED PIN('1', 5)
+
+#ifndef UART_DEBUG
+#define UART_DEBUG LPUART1
+#endif
+
+// No settable constants, see sysinit.c
+#define SYS_FREQUENCY 500000000UL
+
+static inline void spin(volatile uint32_t count) {
+  while (count--) (void) 0;
+}
+
+enum { CLOCK_OFF = 0U, CLOCK_ON_RUN = 1U, CLOCK_ON_RUN_WAIT = 3U };
+static inline void clock_periph(uint32_t index, uint32_t shift, uint32_t val) {
+  volatile uint32_t *r = &CCM->CCGR0;
+  SETBITS(r[index], 3UL << shift, val << shift);
+}
+
+// which peripheral feeds the pin
+static inline void gpio_mux_config(uint16_t index, uint8_t af) {
+  IOMUXC->SW_MUX_CTL_PAD[index] = af;
+}
+
+// which pin feeds the peripheral (2nd stage)
+static inline void periph_mux_config(uint16_t index, uint8_t in) {
+  IOMUXC->SELECT_INPUT[index] = in;
+}
+
+enum { GPIO_MODE_INPUT, GPIO_MODE_OUTPUT };
+enum { GPIO_OTYPE_PUSH_PULL, GPIO_OTYPE_OPEN_DRAIN };
+enum { GPIO_SPEED_LOW, GPIO_SPEED_MEDIUM, GPIO_SPEED_MEDIUM_, GPIO_SPEED_HIGH };
+enum { GPIO_PULL_NONE, GPIO_PULL_DOWN, GPIO_PULL_UP };
+static inline GPIO_Type *gpio_bank(uint16_t pin) {
+  static const GPIO_Type *g[] = {NULL, GPIO1, GPIO2, GPIO3, NULL, GPIO5};
+  return (GPIO_Type *) g[PINBANK(pin)];
+}
+
+// pin driver/pull-up/down configuration (ignore "keeper")
+static inline void gpio_pad_config(uint16_t index, uint8_t type, uint8_t speed,
+                                   uint8_t pull) {
+  bool dopull = pull > 0;
+  if (dopull) --pull;
+  IOMUXC->SW_PAD_CTL_PAD[index] =
+      IOMUXC_SW_PAD_CTL_PAD_SPEED(speed) | IOMUXC_SW_PAD_CTL_PAD_ODE(type) |
+      IOMUXC_SW_PAD_CTL_PAD_SRE(speed >= GPIO_SPEED_HIGH) |
+      IOMUXC_SW_PAD_CTL_PAD_PUE(1) | IOMUXC_SW_PAD_CTL_PAD_PKE(dopull) |
+      IOMUXC_SW_PAD_CTL_PAD_PUS(pull) | IOMUXC_SW_PAD_CTL_PAD_DSE(7);
+}
+
+static inline void gpio_init(uint16_t pin, uint8_t mode, uint8_t type,
+                             uint8_t speed, uint8_t pull) {
+  GPIO_Type *gpio = gpio_bank(pin);
+  uint8_t bit = (uint8_t) PINNO(pin);
+  uint32_t mask = (uint32_t) BIT(PINNO(pin));
+
+  clock_periph(4, CCM_CCGR4_CG1_SHIFT, CLOCK_ON_RUN_WAIT);  // iomuxc_ipg_clk_s
+  switch (PINBANK(pin)) {
+    case 1:
+      gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_00 + bit, 5);
+      gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_00 + bit, type, speed,
+                      pull);
+      clock_periph(1, CCM_CCGR1_CG13_SHIFT, CLOCK_ON_RUN_WAIT);
+      break;
+    case 2:
+      gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_EMC_00 + bit, 5);
+      gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_EMC_00 + bit, type, speed,
+                      pull);
+      clock_periph(0, CCM_CCGR0_CG15_SHIFT, CLOCK_ON_RUN_WAIT);
+      break;
+    case 3:
+      gpio_mux_config(bit < 13
+                          ? kIOMUXC_SW_MUX_CTL_PAD_GPIO_EMC_32 + bit
+                          : kIOMUXC_SW_MUX_CTL_PAD_GPIO_SD_B0_00 + bit - 13,
+                      5);
+      gpio_pad_config(bit < 13
+                          ? kIOMUXC_SW_PAD_CTL_PAD_GPIO_EMC_32 + bit
+                          : kIOMUXC_SW_PAD_CTL_PAD_GPIO_SD_B0_00 + bit - 13,
+                      type, speed, pull);
+      clock_periph(2, CCM_CCGR2_CG13_SHIFT, CLOCK_ON_RUN_WAIT);
+      break;
+    case 5:
+      // TODO(): support sw_mux
+      clock_periph(1, CCM_CCGR1_CG15_SHIFT, CLOCK_ON_RUN_WAIT);
+      break;
+    default:
+      break;
+  }
+
+  gpio->IMR &= ~mask;
+  if (mode == GPIO_MODE_INPUT) {
+    gpio->GDIR &= ~mask;
+  } else {
+    gpio->GDIR |= mask;
+  }
+}
+static inline void gpio_input(uint16_t pin) {
+  gpio_init(pin, GPIO_MODE_INPUT, GPIO_OTYPE_PUSH_PULL, GPIO_SPEED_MEDIUM,
+            GPIO_PULL_NONE);
+}
+static inline void gpio_output(uint16_t pin) {
+  gpio_init(pin, GPIO_MODE_OUTPUT, GPIO_OTYPE_PUSH_PULL, GPIO_SPEED_MEDIUM,
+            GPIO_PULL_NONE);
+}
+
+static inline bool gpio_read(uint16_t pin) {
+  GPIO_Type *gpio = gpio_bank(pin);
+  uint32_t mask = (uint32_t) BIT(PINNO(pin));
+  return gpio->DR & mask;
+}
+static inline void gpio_write(uint16_t pin, bool value) {
+  GPIO_Type *gpio = gpio_bank(pin);
+  uint32_t mask = (uint32_t) BIT(PINNO(pin));
+  if (value) {
+    gpio->DR |= mask;
+  } else {
+    gpio->DR &= ~mask;
+  }
+}
+static inline void gpio_toggle(uint16_t pin) {
+  gpio_write(pin, !gpio_read(pin));
+}
+
+// 14.5 Table 14-4: uart_clk_root
+// see sysinit.c for clocks, (14.7.9: defaults to PLL3/6/1 = 80MHz)
+static inline void uart_init(LPUART_Type *uart, unsigned long baud) {
+  uint8_t af = 2;                           // Alternate function
+  uint16_t mr = 0, pr = 0, mt = 0, pt = 0;  // pins
+  uint32_t freq = 80000000;                 // uart_clk_root frequency
+  if (uart == LPUART1)
+    mt = kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_06,
+    pt = kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_06,
+    mr = kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_07,
+    pr = kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_07;
+  if (uart == LPUART2)
+    mt = kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B1_08,
+    pt = kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B1_08,
+    mr = kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B1_09,
+    pr = kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B1_09;
+
+  if (uart == LPUART1) clock_periph(5, CCM_CCGR5_CG12_SHIFT, CLOCK_ON_RUN_WAIT);
+  if (uart == LPUART2) clock_periph(0, CCM_CCGR0_CG14_SHIFT, CLOCK_ON_RUN_WAIT);
+  clock_periph(4, CCM_CCGR4_CG1_SHIFT, CLOCK_ON_RUN_WAIT);  // iomuxc_ipg_clk_s
+  gpio_mux_config(mt, af);
+  gpio_pad_config(pt, GPIO_OTYPE_PUSH_PULL, GPIO_SPEED_MEDIUM, GPIO_PULL_UP);
+  gpio_mux_config(mr, af);
+  gpio_pad_config(pr, GPIO_OTYPE_PUSH_PULL, GPIO_SPEED_MEDIUM, GPIO_PULL_UP);
+
+  uart->GLOBAL |= LPUART_GLOBAL_RST_MASK;  // reset, CTRL = 0, defaults
+  uart->GLOBAL &= ~LPUART_GLOBAL_RST_MASK;
+  SETBITS(uart->BAUD,
+          LPUART_BAUD_OSR_MASK | LPUART_BAUD_SBR_MASK | LPUART_BAUD_SBNS_MASK,
+          LPUART_BAUD_OSR(16 - 1) |
+              LPUART_BAUD_SBR(freq / (16 * baud)));  // Rx sample at 16x
+  SETBITS(uart->CTRL,
+          LPUART_CTRL_PE_MASK | LPUART_CTRL_M_MASK | LPUART_CTRL_ILT_MASK |
+              LPUART_CTRL_IDLECFG_MASK,
+          LPUART_CTRL_IDLECFG(1) | LPUART_CTRL_ILT(1) |
+              LPUART_BAUD_SBNS(0));  // no parity, idle 2 chars after 1 stop bit
+  uart->CTRL |= LPUART_CTRL_TE_MASK | LPUART_CTRL_RE_MASK;
+}
+
+static inline void uart_write_byte(LPUART_Type *uart, uint8_t byte) {
+  uart->DATA = byte;
+  while ((uart->STAT & LPUART_STAT_TDRE_MASK) == 0) spin(1);
+}
+static inline void uart_write_buf(LPUART_Type *uart, char *buf, size_t len) {
+  while (len-- > 0) uart_write_byte(uart, *(uint8_t *) buf++);
+}
+static inline int uart_read_ready(LPUART_Type *uart) {
+  (void) uart;
+  return uart->STAT & LPUART_STAT_RDRF_MASK;
+}
+static inline uint8_t uart_read_byte(LPUART_Type *uart) {
+  return (uint8_t) (uart->DATA & 255);
+}
+
+// TODO(NXP): get RNG usage specs
+static inline void rng_init(void) {
+}
+#include <stdlib.h>
+static inline uint32_t rng_read(void) {
+  return (uint32_t) rand();
+}
+
+// - PHY has no xtal, XI driven from ENET_REF_CLK1 (labeled as ENET_TX_CLK
+// (GPIO_AD_B0_08)), generated by the MCU
+// - PHY RST connected to GPIO1.4 (GPIO_AD_B0_04); INTRP/NAND_TREE connected to
+// GPIO1.22 (GPIO_AD_B1_06)
+// - 37.4 REF_CLK1 is RMII mode reference clock for Rx, Tx, and SMI; it is I/O
+// - 11.4.2 IOMUXC_GPR_GPR1 bit 17: ENET_REF_CLK_DIR --> 1 ENET_REF_CLK is
+// output driven by ref_enetpll0
+// - 14.6.1.3.4 Ethernet PLL (PLL6)
+static inline void ethernet_init(void) {
+  gpio_init(PIN('1', 4), GPIO_MODE_OUTPUT, GPIO_OTYPE_PUSH_PULL,
+            GPIO_SPEED_MEDIUM, GPIO_PULL_UP);  // set GPIO1.4 as GPIO (PHY \RST)
+  gpio_write(PIN('1', 4), 0);                  // reset PHY
+
+  gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_08,
+                  4);  // set for ENET_REF_CLK1
+  IOMUXC->SW_MUX_CTL_PAD[kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_08] |=
+      IOMUXC_SW_MUX_CTL_PAD_SION(1);  // loop signal back from pin
+  periph_mux_config(kIOMUXC_ENET_RMII_SELECT_INPUT,
+                    1);  // drive peripheral from B0_08, so RMII clock is taken
+                         // from ENET_REF_CLK1
+  gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_08, GPIO_OTYPE_PUSH_PULL,
+                  GPIO_SPEED_HIGH, GPIO_PULL_UP);
+  gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_09, 0);  // set for RXDATA1
+  periph_mux_config(kIOMUXC_ENET_RX_DATA1_SELECT_INPUT,
+                    1);  // drive peripheral from B0_09
+  gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_09, GPIO_OTYPE_PUSH_PULL,
+                  GPIO_SPEED_HIGH, GPIO_PULL_UP);
+  gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_10, 0);  // set for RXDATA0
+  periph_mux_config(kIOMUXC_ENET_RX_DATA0_SELECT_INPUT,
+                    1);  // drive peripheral from B0_10
+  gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_10, GPIO_OTYPE_PUSH_PULL,
+                  GPIO_SPEED_HIGH, GPIO_PULL_UP);
+  gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_11, 0);  // set for CRS
+  periph_mux_config(kIOMUXC_ENET_RX_EN_SELECT_INPUT,
+                    1);  // drive peripheral from B0_11
+  gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_11, GPIO_OTYPE_PUSH_PULL,
+                  GPIO_SPEED_HIGH, GPIO_PULL_UP);
+  gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_12, 0);  // set for RXERR
+  periph_mux_config(kIOMUXC_ENET_RX_ERR_SELECT_INPUT,
+                    1);  // drive peripheral from B0_12
+  gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_12, GPIO_OTYPE_PUSH_PULL,
+                  GPIO_SPEED_HIGH, GPIO_PULL_UP);
+  gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_13, 0);  // set for TXEN
+  gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_13, GPIO_OTYPE_PUSH_PULL,
+                  GPIO_SPEED_HIGH, GPIO_PULL_UP);
+  gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_14, 0);  // set for TXDATA0
+  gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_14, GPIO_OTYPE_PUSH_PULL,
+                  GPIO_SPEED_HIGH, GPIO_PULL_UP);
+  gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_15, 0);  // set for TXDATA1
+  gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_15, GPIO_OTYPE_PUSH_PULL,
+                  GPIO_SPEED_HIGH, GPIO_PULL_UP);
+  gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_EMC_40, 4);  // set for MDIO
+  periph_mux_config(kIOMUXC_ENET_MDIO_SELECT_INPUT,
+                    2);  // drive peripheral from EMC_40
+  gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_EMC_40, GPIO_OTYPE_PUSH_PULL,
+                  GPIO_SPEED_MEDIUM, GPIO_PULL_UP);
+  gpio_mux_config(kIOMUXC_SW_MUX_CTL_PAD_GPIO_EMC_41, 4);  // set for MDC
+  gpio_pad_config(kIOMUXC_SW_PAD_CTL_PAD_GPIO_EMC_41, GPIO_OTYPE_PUSH_PULL,
+                  GPIO_SPEED_MEDIUM, GPIO_PULL_UP);
+
+  gpio_init(PIN('1', 22), GPIO_MODE_OUTPUT, GPIO_OTYPE_PUSH_PULL,
+            GPIO_SPEED_MEDIUM,
+            GPIO_PULL_UP);      // set GPIO1.22 as GPIO (PHY INTRP/NAND_TREE)
+  gpio_write(PIN('1', 22), 1);  // prevent NAND_TREE
+  // 14.8.9 Use 500MHz reference and generate 50MHz. This is done at sysinit.c,
+  // as we use this source to clock the core
+  spin(10000);                 // keep PHY RST low for a while
+  gpio_write(PIN('1', 4), 1);  // deassert RST
+  gpio_init(PIN('1', 22), GPIO_MODE_INPUT, 0, GPIO_SPEED_MEDIUM,
+            GPIO_PULL_UP);  // setup IRQ (pulled-up)(not used)
+
+  IOMUXC_GPR->GPR1 |=
+      IOMUXC_GPR_GPR1_ENET_REF_CLK_DIR(1);  // Set ENET_REF_CLK1 as output
+  clock_periph(1, CCM_CCGR1_CG5_SHIFT, CLOCK_ON_RUN_WAIT);  // enet_ipg_clk
+  NVIC_EnableIRQ(ENET_IRQn);  // Setup Ethernet IRQ handler
+}
+
+// Helper macro for MAC generation
+#define GENERATE_LOCALLY_ADMINISTERED_MAC() \
+  { 2, 0, 2, 5, 7, 91 }
+//    *((uint32_t *)(uintptr_t)&uid[0]) = OCOTP->CFG0;
+//    *((uint32_t *)(uintptr_t)&uid[4]) = OCOTP->CFG1;
diff --git a/examples/nxp/rt1020-make-baremetal/link.ld b/examples/nxp/rt1020-evk-make-baremetal-builtin/link.ld
similarity index 100%
rename from examples/nxp/rt1020-make-baremetal/link.ld
rename to examples/nxp/rt1020-evk-make-baremetal-builtin/link.ld
diff --git a/examples/nxp/rt1020-make-baremetal/link2.ld b/examples/nxp/rt1020-evk-make-baremetal-builtin/link2.ld
similarity index 100%
rename from examples/nxp/rt1020-make-baremetal/link2.ld
rename to examples/nxp/rt1020-evk-make-baremetal-builtin/link2.ld
diff --git a/examples/nxp/rt1020-evk-make-baremetal-builtin/link_ram.ld b/examples/nxp/rt1020-evk-make-baremetal-builtin/link_ram.ld
new file mode 100644
index 0000000000..1240f1d27e
--- /dev/null
+++ b/examples/nxp/rt1020-evk-make-baremetal-builtin/link_ram.ld
@@ -0,0 +1,16 @@
+ENTRY(Reset_Handler);
+MEMORY {
+  itcram(rx)       : ORIGIN = 0x00000000, LENGTH = 64k
+  dtcram(rw)       : ORIGIN = 0x20000000, LENGTH = 64k
+  ocram(rw)        : ORIGIN = 0x20200000, LENGTH = 128k   # This is cached !
+}
+__StackTop = ORIGIN(dtcram) + LENGTH(dtcram);
+
+SECTIONS {
+  .irq  : { KEEP(*(.isr_vector)) }  > itcram
+  .text : { *(.text* .text.*) *(.rodata*) ; } > itcram
+  .data : { __data_start__ = .; *(.data SORT(.data.*)) __data_end__ = .; } > dtcram AT > itcram
+  __etext = LOADADDR(.data);
+  .bss  : { __bss_start__ = .; *(.bss SORT(.bss.*) COMMON) __bss_end__ = .; } > dtcram
+  _end = .;
+}
diff --git a/examples/nxp/rt1020-make-baremetal/main.c b/examples/nxp/rt1020-evk-make-baremetal-builtin/main.c
similarity index 73%
rename from examples/nxp/rt1020-make-baremetal/main.c
rename to examples/nxp/rt1020-evk-make-baremetal-builtin/main.c
index c7d12673ca..9f60d034bf 100644
--- a/examples/nxp/rt1020-make-baremetal/main.c
+++ b/examples/nxp/rt1020-evk-make-baremetal-builtin/main.c
@@ -3,7 +3,7 @@
 
 #include "hal.h"
 #include "mongoose.h"
-// #include "net.h"
+#include "net.h"
 
 #define BLINK_PERIOD_MS 1000  // LED blinking period in millis
 
@@ -22,26 +22,17 @@ void mg_random(void *buf, size_t len) {  // Use on-board RNG
     memcpy((char *) buf + n, &r, n + sizeof(r) > len ? len - n : sizeof(r));
   }
 }
-
 static void timer_fn(void *arg) {
-  //gpio_toggle(LED);                                      // Blink LED
-  //struct mg_tcpip_if *ifp = arg;                         // And show
-  //const char *names[] = {"down", "up", "req", "ready"};  // network stats
-  //MG_INFO(("Ethernet: %s, IP: %M, rx:%u, tx:%u, dr:%u, er:%u",
-  //         names[ifp->state], mg_print_ip4, &ifp->ip, ifp->nrecv, ifp->nsent,
-  //         ifp->ndrop, ifp->nerr));
-  MG_INFO(("%p", arg));
+  gpio_toggle(LED);                                      // Blink LED
+  struct mg_tcpip_if *ifp = arg;                         // And show
+  const char *names[] = {"down", "up", "req", "ready"};  // network stats
+  MG_INFO(("Ethernet: %s, IP: %M, rx:%u, tx:%u, dr:%u, er:%u",
+           names[ifp->state], mg_print_ip4, &ifp->ip, ifp->nrecv, ifp->nsent,
+           ifp->ndrop, ifp->nerr));
 }
 
 int main(void) {
   gpio_output(LED);               // Setup blue LED
-
-  for (;;) {
-    gpio_toggle(LED);
-    spin(99999);
-  }
-
-
   uart_init(UART_DEBUG, 115200);  // Initialise debug printf
   ethernet_init();                // Initialise ethernet pins
   MG_INFO(("Starting, CPU freq %g MHz", (double) SystemCoreClock / 1000000));
@@ -49,17 +40,15 @@ int main(void) {
   struct mg_mgr mgr;        // Initialise
   mg_mgr_init(&mgr);        // Mongoose event manager
   mg_log_set(MG_LL_DEBUG);  // Set log level
-  mg_timer_add(&mgr, BLINK_PERIOD_MS, MG_TIMER_REPEAT, timer_fn, NULL);
 
-#if 0
   // Initialise Mongoose network stack
-  struct mg_tcpip_driver_stm32_data driver_data = {.mdc_cr = 4};
+  struct mg_tcpip_driver_imxrt1020_data driver_data = {.mdc_cr = 4};
   struct mg_tcpip_if mif = {.mac = GENERATE_LOCALLY_ADMINISTERED_MAC(),
                             // Uncomment below for static configuration:
                             // .ip = mg_htonl(MG_U32(192, 168, 0, 223)),
                             // .mask = mg_htonl(MG_U32(255, 255, 255, 0)),
                             // .gw = mg_htonl(MG_U32(192, 168, 0, 1)),
-                            .driver = &mg_tcpip_driver_stm32,
+                            .driver = &mg_tcpip_driver_imxrt1020,
                             .driver_data = &driver_data};
   mg_tcpip_init(&mgr, &mif);
   mg_timer_add(&mgr, BLINK_PERIOD_MS, MG_TIMER_REPEAT, timer_fn, &mif);
@@ -70,8 +59,7 @@ int main(void) {
   }
 
   MG_INFO(("Initialising application..."));
-  web_init(&mgr);
-#endif
+//  web_init(&mgr);
 
   MG_INFO(("Starting event loop"));
   for (;;) {
diff --git a/examples/nxp/rt1020-make-baremetal/mongoose.c b/examples/nxp/rt1020-evk-make-baremetal-builtin/mongoose.c
similarity index 100%
rename from examples/nxp/rt1020-make-baremetal/mongoose.c
rename to examples/nxp/rt1020-evk-make-baremetal-builtin/mongoose.c
diff --git a/examples/nxp/rt1020-make-baremetal/mongoose.h b/examples/nxp/rt1020-evk-make-baremetal-builtin/mongoose.h
similarity index 100%
rename from examples/nxp/rt1020-make-baremetal/mongoose.h
rename to examples/nxp/rt1020-evk-make-baremetal-builtin/mongoose.h
diff --git a/examples/nxp/rt1020-evk-make-baremetal-builtin/net.c b/examples/nxp/rt1020-evk-make-baremetal-builtin/net.c
new file mode 120000
index 0000000000..fe0e6f06e7
--- /dev/null
+++ b/examples/nxp/rt1020-evk-make-baremetal-builtin/net.c
@@ -0,0 +1 @@
+../../device-dashboard/net.c
\ No newline at end of file
diff --git a/examples/nxp/rt1020-evk-make-baremetal-builtin/net.h b/examples/nxp/rt1020-evk-make-baremetal-builtin/net.h
new file mode 120000
index 0000000000..9de896ef4e
--- /dev/null
+++ b/examples/nxp/rt1020-evk-make-baremetal-builtin/net.h
@@ -0,0 +1 @@
+../../device-dashboard/net.h
\ No newline at end of file
diff --git a/examples/nxp/rt1020-evk-make-baremetal-builtin/packed_fs.c b/examples/nxp/rt1020-evk-make-baremetal-builtin/packed_fs.c
new file mode 120000
index 0000000000..e06bf09258
--- /dev/null
+++ b/examples/nxp/rt1020-evk-make-baremetal-builtin/packed_fs.c
@@ -0,0 +1 @@
+../../device-dashboard/packed_fs.c
\ No newline at end of file
diff --git a/examples/nxp/rt1020-make-baremetal/syscalls.c b/examples/nxp/rt1020-evk-make-baremetal-builtin/syscalls.c
similarity index 95%
rename from examples/nxp/rt1020-make-baremetal/syscalls.c
rename to examples/nxp/rt1020-evk-make-baremetal-builtin/syscalls.c
index a7c8d622c6..6fef1007c4 100644
--- a/examples/nxp/rt1020-make-baremetal/syscalls.c
+++ b/examples/nxp/rt1020-evk-make-baremetal-builtin/syscalls.c
@@ -9,12 +9,12 @@ int _fstat(int fd, struct stat *st) {
 }
 
 void *_sbrk(int incr) {
-  extern char __end__;
+  extern char _end;
   static unsigned char *heap = NULL;
   unsigned char *prev_heap;
   unsigned char x = 0, *heap_end = (unsigned char *)((size_t) &x - 512);
   (void) x;
-  if (heap == NULL) heap = (unsigned char *) &__end__;
+  if (heap == NULL) heap = (unsigned char *) &_end;
   prev_heap = heap;
   if (heap + incr > heap_end) return (void *) -1;
   heap += incr;
diff --git a/examples/nxp/rt1020-evk-make-baremetal-builtin/sysinit.c b/examples/nxp/rt1020-evk-make-baremetal-builtin/sysinit.c
new file mode 100644
index 0000000000..d60a5254e2
--- /dev/null
+++ b/examples/nxp/rt1020-evk-make-baremetal-builtin/sysinit.c
@@ -0,0 +1,106 @@
+// Copyright (c) 2023 Cesanta Software Limited
+// All rights reserved
+//
+// This file contains essentials required by the CMSIS:
+// uint32_t SystemCoreClock - holds the system core clock value
+// SystemInit() - initialises the system, e.g. sets up clocks
+
+#include "hal.h"
+
+uint32_t SystemCoreClock = SYS_FREQUENCY;
+
+// - 14.4, Figure 14-2: clock tree
+// - 14.7.4: ARM_PODF defaults to /1
+// - 14.7.5: AHB_PODF defaults to /1; PERIPH_CLK_SEL defaults to derive clock
+// from pre_periph_clk_sel
+// - 14.7.6: PRE_PERIPH_CLK_SEL defaults to derive clock from PLL2 PFD3.
+// - (For 528MHz operation, we need to set it to derive clock from PLL2, but
+// this chip max is 500 MHz).
+// - 14.6.1.3.1 System PLL (PLL2); 13.3.2.2 PLLs; 14.6.1.4 Phase Fractional
+// Dividers (PFD)
+// - 14.8.2: PLL2 is powered off and bypassed to 24MHz
+// - 14.8.11: PFD defaults to 18/16 but Figure 14-2 shows half the value
+// ("divider")
+// - For 500MHz operation, we need to set PRE_PERIPH_CLK_SEL to derive clock
+// from divided PLL6
+// - 14.8.9: configure PLL6 to generate a 500MHz clock
+// - Datasheet 4.1.3: System frequency/Bus frequency max 500/125MHz respectively
+// (AHB/IPG)
+// - MCUXpresso: IPG_CLK_ROOT <= 125MHz; PERCLK_CLK_ROOT <= 62.5MHz
+// - Datasheet 4.8.4.1.1/2: the processor clock frequency must exceed twice the
+// ENET_RX_CLK/ENET_TX_CLK frequency.
+// - Datasheet 4.8.4.2: no details for RMII (above is for MII), assumed 50MHz
+// min processor clock
+// - Datasheet 4.1.3, Table 11: "Overdrive" run mode requires 1.25V core voltage
+// minimum
+void SystemInit(void) {  // Called automatically by startup code (ints masked)
+  SCB->CPACR |= ((3UL << 10 * 2) | (3UL << 11 * 2));  // Enable FPU
+  asm("DSB");
+  asm("ISB");
+  // 53.4.2: Disable watchdog after reset (unlocked)
+  RTWDOG->CS &= ~RTWDOG_CS_EN_MASK;
+  RTWDOG->TOVAL = 0xFFFF;
+  while (RTWDOG->CS & RTWDOG_CS_ULK_MASK) spin(1);  // wait for lock
+  while ((RTWDOG->CS & RTWDOG_CS_RCS_MASK) == 0)
+    spin(1);  // wait for new config
+  // Set VDD_SOC to 1.25V
+  SETBITS(DCDC->REG3, DCDC_REG3_TRG_MASK, DCDC_REG3_TRG(0x12));
+  while ((DCDC->REG0 & DCDC_REG0_STS_DC_OK_MASK) == 0)
+    spin(1);  // Wait for DCDC_STS_DC_OK
+  // 14.8.9 Init 500MHz reference, clock the M7 core with it, generate 50MHz for
+  // ENET and RMII.
+  SETBITS(CCM_ANALOG->PLL_ENET, CCM_ANALOG_PLL_ENET_BYPASS_CLK_SRC_MASK,
+          CCM_ANALOG_PLL_ENET_BYPASS_MASK |
+              CCM_ANALOG_PLL_ENET_BYPASS_CLK_SRC(0));  // bypass to 24MHz osc
+  SETBITS(
+      CCM_ANALOG->PLL_ENET,
+      CCM_ANALOG_PLL_ENET_DIV_SELECT_MASK | CCM_ANALOG_PLL_ENET_POWERDOWN_MASK,
+      CCM_ANALOG_PLL_ENET_DIV_SELECT(1) | CCM_ANALOG_PLL_ENET_ENABLE_MASK |
+          CCM_ANALOG_PLL_ENET_ENET_500M_REF_EN_MASK);  // setup PLL
+  while ((CCM_ANALOG->PLL_ENET & CCM_ANALOG_PLL_ENET_LOCK_MASK) == 0)
+    spin(1);  // wait until it is stable
+  CCM_ANALOG->PLL_ENET &=
+      ~CCM_ANALOG_PLL_ENET_BYPASS_MASK;  // Disable Bypass (switch to PLL)
+  SETBITS(CCM->CBCDR, CCM_CBCDR_IPG_PODF_MASK,
+          CCM_CBCDR_IPG_PODF(3));  // Set IPG divider /4 (125MHz)
+  SETBITS(CCM->CSCMR1, CCM_CSCMR1_PERCLK_PODF_MASK,
+          CCM_CSCMR1_PERCLK_PODF(1));  // Set PERCLK divider /2 (62.5MHz)
+  SETBITS(CCM->CBCMR, CCM_CBCMR_PRE_PERIPH_CLK_SEL_MASK,
+          CCM_CBCMR_PRE_PERIPH_CLK_SEL(3));  // run from 500MHz clock
+  // 14.5 Table 14-4: uart_clk_root
+  // 14.4: uart_clk_root = PLL3/6 or OSC; CCM_CSCDR1 (14.7.9) defaults to
+  // PLL3/6/1
+  CCM_ANALOG->PLL_USB1 |= CCM_ANALOG_PLL_USB1_POWER_MASK;  // Power PLL on
+  while ((CCM_ANALOG->PLL_USB1 & CCM_ANALOG_PLL_USB1_LOCK_MASK) == 0)
+    spin(1);  // wait until it is stable
+  CCM_ANALOG->PLL_USB1 &=
+      ~CCM_ANALOG_PLL_USB1_BYPASS_MASK;  // Disable Bypass (switch to PLL)
+  rng_init();                            // Initialise random number generator
+  // NXP startup code calls SystemInit BEFORE initializing RAM...
+  SysTick_Config(SYS_FREQUENCY / 1000);  // Sys tick every 1ms
+}
+
+#if 0
+__attribute__((section(".cfg"), used)) uint32_t __cfg[] = {0x1234abcd};
+
+extern uint32_t __isr_vector[];
+extern uint32_t __ivt_boot_data[];
+
+__attribute__((section(".ivt"), used)) uint32_t __ivt[8] = {
+    0x412000d1,                  // header: 41 - version, 2000 size, d1 tag
+    (uint32_t) __isr_vector,     // entry
+    0,                           // reserved
+    0,                           // dcd
+    (uint32_t) __ivt_boot_data,  // boot data
+    (uint32_t) __ivt,            // this is us - ivt absolute address
+    0,                           // csf absolute address
+    0,                           // reserved for HAB
+};
+
+__attribute__((section(".ivt"), used)) uint32_t __ivt_boot_data[] = {
+    0,          // boot start location
+    64 * 1024,  // size
+    0,          // Plugin flag
+    0Xffffffff  // empty - extra data word
+};
+#endif
diff --git a/examples/nxp/rt1020-make-baremetal/sysinit2.c b/examples/nxp/rt1020-evk-make-baremetal-builtin/sysinit2.c
similarity index 100%
rename from examples/nxp/rt1020-make-baremetal/sysinit2.c
rename to examples/nxp/rt1020-evk-make-baremetal-builtin/sysinit2.c
diff --git a/examples/nxp/rt1020-make-baremetal/hal.h b/examples/nxp/rt1020-make-baremetal/hal.h
deleted file mode 100644
index 7ce32e1057..0000000000
--- a/examples/nxp/rt1020-make-baremetal/hal.h
+++ /dev/null
@@ -1,166 +0,0 @@
-// Copyright (c) 2023 Cesanta Software Limited
-// All rights reserved
-// https://www.nxp.com/webapp/Download?colCode=IMXRT1020RM
-// https://cache.nxp.com/secured/assets/documents/en/user-guide/MIMXRT1020EVKHUG.pdf
-
-#pragma once
-
-#include "MIMXRT1021.h"
-// #include "drivers/fsl_clock.h"
-
-#include <stdbool.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-
-#define BIT(x) (1UL << (x))
-#define SETBITS(R, CLEARMASK, SETMASK) (R) = ((R) & ~(CLEARMASK)) | (SETMASK)
-#define PIN(bank, num) ((((bank) - 'A') << 8) | (num))
-#define PINNO(pin) (pin & 255)
-#define PINBANK(pin) (pin >> 8)
-
-#define LED PIN('A', 6)  // Use LED for blinking, GPIO_AD_B0_06. RM tbl 9-1
-
-#ifndef UART_DEBUG
-#define UART_DEBUG LPUART1
-#endif
-
-#define SYS_FREQUENCY 16000000
-
-static inline void spin(volatile uint32_t count) {
-  while (count--) (void) 0;
-}
-
-static inline GPIO_Type *gpio_bank(uint16_t pin) {
-  switch (PINBANK(pin)) {
-    case 1: return (GPIO_Type *) GPIO1_BASE;
-    case 2: return (GPIO_Type *) GPIO2_BASE;
-    case 3: return (GPIO_Type *) GPIO3_BASE;
-    case 5: return (GPIO_Type *) GPIO5_BASE;
-    default: return NULL;
-  }
-}
-
-enum { GPIO_MODE_INPUT, GPIO_MODE_OUTPUT, GPIO_MODE_AF, GPIO_MODE_ANALOG };
-// enum { GPIO_OTYPE_PUSH_PULL, GPIO_OTYPE_OPEN_DRAIN };
-// enum { GPIO_PULL_NONE, GPIO_PULL_UP, GPIO_PULL_DOWN };
-
-#if 0
-static inline void CLOCK_ControlGate(clock_ip_name_t name,
-                                     clock_gate_value_t value) {
-  uint32_t index = ((uint32_t) name) >> 8U;
-  uint32_t shift = ((uint32_t) name) & 0x1FU;
-  volatile uint32_t *reg;
-  assert(index <= 6UL);
-  reg = (volatile uint32_t *) ((uint32_t) ((volatile uint32_t *) &CCM->CCGR0) +
-                               sizeof(volatile uint32_t *) * index);
-  SDK_ATOMIC_LOCAL_CLEAR_AND_SET(reg, (3UL << shift),
-                                 (((uint32_t) value) << shift));
-}
-
-static inline void CLOCK_EnableClock(clock_ip_name_t name) {
-  CLOCK_ControlGate(name, kCLOCK_ClockNeededRunWait);
-}
-#endif
-
-enum { CLOCK_OFF = 0U, CLOCK_ON_RUN = 1U, CLOCK_ON_RUN_WAIT = 3U };
-static inline void clock_periph(uint32_t index, uint32_t shift, uint32_t val) {
-  volatile uint32_t *r = &CCM->CCGR0;
-  SETBITS(r[index], 3UL << shift, val << shift);
-}
-
-static inline void gpio_init(uint16_t pin, uint8_t mode) {
-  GPIO_Type *gpio = gpio_bank(pin);
-  uint32_t mask = (uint32_t) BIT(PINNO(pin));
-
-  // Enable clock
-  switch (PINBANK(pin)) {
-    case 1: clock_periph(1, CCM_CCGR1_CG13_SHIFT, CLOCK_ON_RUN_WAIT); break;
-    case 2: clock_periph(0, CCM_CCGR0_CG15_SHIFT, CLOCK_ON_RUN_WAIT); break;
-    case 3: clock_periph(2, CCM_CCGR2_CG13_SHIFT, CLOCK_ON_RUN_WAIT); break;
-    case 5: clock_periph(1, CCM_CCGR1_CG15_SHIFT, CLOCK_ON_RUN_WAIT); break;
-    default: break;
-  }
-
-  gpio->IMR &= ~mask;
-  if (mode == GPIO_MODE_INPUT) {
-    gpio->GDIR &= ~mask;
-  } else {
-    gpio->GDIR |= mask;
-  }
-}
-static inline void gpio_input(uint16_t pin) {
-  gpio_init(pin, GPIO_MODE_INPUT);
-}
-static inline void gpio_output(uint16_t pin) {
-  gpio_init(pin, GPIO_MODE_OUTPUT);
-}
-static inline bool gpio_read(uint16_t pin) {
-  GPIO_Type *gpio = gpio_bank(pin);
-  uint32_t mask = (uint32_t) BIT(PINNO(pin));
-  return gpio->DR & mask;
-}
-static inline void gpio_write(uint16_t pin, bool value) {
-  GPIO_Type *gpio = gpio_bank(pin);
-  uint32_t mask = (uint32_t) BIT(PINNO(pin));
-  if (value) {
-    gpio->DR |= mask;
-  } else {
-    gpio->DR &= ~mask;
-  }
-}
-static inline void gpio_toggle(uint16_t pin) {
-  gpio_write(pin, !gpio_read(pin));
-}
-
-static inline void uart_init(LPUART_Type *uart, unsigned long baud) {
-  (void) uart, (void) baud;
-}
-#if 0
-
-static inline void uart_init(LPUART_Type *uart, unsigned long baud) {
-  uint8_t af = 7;           // Alternate function
-  uint16_t rx = 0, tx = 0;  // pins
-  uint32_t freq = 0;        // Bus frequency. UART1 is on APB2, rest on APB1
-
-  if (uart == USART1) freq = APB2_FREQUENCY, RCC->APB2ENR |= BIT(4);
-  if (uart == USART2) freq = APB1_FREQUENCY, RCC->APB1ENR |= BIT(17);
-  if (uart == USART3) freq = APB1_FREQUENCY, RCC->APB1ENR |= BIT(18);
-
-  if (uart == USART1) tx = PIN('A', 9), rx = PIN('A', 10);
-  if (uart == USART2) tx = PIN('A', 2), rx = PIN('A', 3);
-  if (uart == USART3) tx = PIN('D', 8), rx = PIN('D', 9);
-
-  gpio_init(tx, GPIO_MODE_AF, GPIO_OTYPE_PUSH_PULL, GPIO_SPEED_HIGH, 0, af);
-  gpio_init(rx, GPIO_MODE_AF, GPIO_OTYPE_PUSH_PULL, GPIO_SPEED_HIGH, 0, af);
-  uart->CR1 = 0;                          // Disable this UART
-  uart->BRR = freq / baud;                // Set baud rate
-  uart->CR1 |= BIT(0) | BIT(2) | BIT(3);  // Set UE, RE, TE
-}
-#endif
-static inline void uart_write_byte(LPUART_Type *uart, uint8_t byte) {
-  // uart->TDR = byte;
-  // while ((uart->ISR & BIT(7)) == 0) spin(1);
-  (void) uart, (void) byte;
-}
-static inline void uart_write_buf(LPUART_Type *uart, char *buf, size_t len) {
-  while (len-- > 0) uart_write_byte(uart, *(uint8_t *) buf++);
-}
-static inline int uart_read_ready(LPUART_Type *uart) {
-  (void) uart;
-  // return uart->ISR & BIT(5);  // If RXNE bit is set, data is ready
-  return 0;
-}
-static inline uint8_t uart_read_byte(LPUART_Type *uart) {
-  (void) uart;
-  // return (uint8_t) (uart->RDR & 255);
-  return 0;
-}
-
-static inline void rng_init(void) {
-}
-static inline uint32_t rng_read(void) {
-  return 42;
-}
-static inline void ethernet_init(void) {
-}
diff --git a/examples/nxp/rt1020-make-baremetal/sysinit.c b/examples/nxp/rt1020-make-baremetal/sysinit.c
deleted file mode 100644
index b065eef455..0000000000
--- a/examples/nxp/rt1020-make-baremetal/sysinit.c
+++ /dev/null
@@ -1,44 +0,0 @@
-// Copyright (c) 2023 Cesanta Software Limited
-// All rights reserved
-//
-// This file contains essentials required by the CMSIS:
-// uint32_t SystemCoreClock - holds the system core clock value
-// SystemInit() - initialises the system, e.g. sets up clocks
-
-#include "hal.h"
-
-uint32_t SystemCoreClock = SYS_FREQUENCY;
-
-void SystemInit(void) {  // Called automatically by startup code
-  rng_init();            // Initialise random number generator
-  SysTick_Config(SystemCoreClock / 1000);  // Sys tick every 1ms
-}
-
-void _start(void) {
-  extern void main(void);
-  main();
-  for (;;) (void) 0;
-}
-
-__attribute__((section(".cfg"), used)) uint32_t __cfg[] = {0x1234abcd};
-
-extern uint32_t __isr_vector[];
-extern uint32_t __ivt_boot_data[];
-
-__attribute__((section(".ivt"), used)) uint32_t __ivt[8] = {
-    0x412000d1,                  // header: 41 - version, 2000 size, d1 tag
-    (uint32_t) __isr_vector,     // entry
-    0,                           // reserved
-    0,                           // dcd
-    (uint32_t) __ivt_boot_data,  // boot data
-    (uint32_t) __ivt,            // this is us - ivt absolute address
-    0,                           // csf absolute address
-    0,                           // reserved for HAB
-};
-
-__attribute__((section(".ivt"), used)) uint32_t __ivt_boot_data[] = {
-    0,          // boot start location
-    64 * 1024,  // size
-    0,          // Plugin flag
-    0Xffffffff  // empty - extra data word
-};
diff --git a/mongoose.c b/mongoose.c
index 20db1ee34c..09089d1118 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -4017,273 +4017,6 @@ struct mg_connection *mg_mqtt_listen(struct mg_mgr *mgr, const char *url,
   return c;
 }
 
-#ifdef MG_ENABLE_LINES
-#line 1 "src/net.c"
-#endif
-
-
-
-
-
-
-
-
-size_t mg_vprintf(struct mg_connection *c, const char *fmt, va_list *ap) {
-  size_t old = c->send.len;
-  mg_vxprintf(mg_pfn_iobuf, &c->send, fmt, ap);
-  return c->send.len - old;
-}
-
-size_t mg_printf(struct mg_connection *c, const char *fmt, ...) {
-  size_t len = 0;
-  va_list ap;
-  va_start(ap, fmt);
-  len = mg_vprintf(c, fmt, &ap);
-  va_end(ap);
-  return len;
-}
-
-static bool mg_atonl(struct mg_str str, struct mg_addr *addr) {
-  uint32_t localhost = mg_htonl(0x7f000001);
-  if (mg_vcasecmp(&str, "localhost") != 0) return false;
-  memcpy(addr->ip, &localhost, sizeof(uint32_t));
-  addr->is_ip6 = false;
-  return true;
-}
-
-static bool mg_atone(struct mg_str str, struct mg_addr *addr) {
-  if (str.len > 0) return false;
-  memset(addr->ip, 0, sizeof(addr->ip));
-  addr->is_ip6 = false;
-  return true;
-}
-
-static bool mg_aton4(struct mg_str str, struct mg_addr *addr) {
-  uint8_t data[4] = {0, 0, 0, 0};
-  size_t i, num_dots = 0;
-  for (i = 0; i < str.len; i++) {
-    if (str.ptr[i] >= '0' && str.ptr[i] <= '9') {
-      int octet = data[num_dots] * 10 + (str.ptr[i] - '0');
-      if (octet > 255) return false;
-      data[num_dots] = (uint8_t) octet;
-    } else if (str.ptr[i] == '.') {
-      if (num_dots >= 3 || i == 0 || str.ptr[i - 1] == '.') return false;
-      num_dots++;
-    } else {
-      return false;
-    }
-  }
-  if (num_dots != 3 || str.ptr[i - 1] == '.') return false;
-  memcpy(&addr->ip, data, sizeof(data));
-  addr->is_ip6 = false;
-  return true;
-}
-
-static bool mg_v4mapped(struct mg_str str, struct mg_addr *addr) {
-  int i;
-  uint32_t ipv4;
-  if (str.len < 14) return false;
-  if (str.ptr[0] != ':' || str.ptr[1] != ':' || str.ptr[6] != ':') return false;
-  for (i = 2; i < 6; i++) {
-    if (str.ptr[i] != 'f' && str.ptr[i] != 'F') return false;
-  }
-  // struct mg_str s = mg_str_n(&str.ptr[7], str.len - 7);
-  if (!mg_aton4(mg_str_n(&str.ptr[7], str.len - 7), addr)) return false;
-  memcpy(&ipv4, addr->ip, sizeof(ipv4));
-  memset(addr->ip, 0, sizeof(addr->ip));
-  addr->ip[10] = addr->ip[11] = 255;
-  memcpy(&addr->ip[12], &ipv4, 4);
-  addr->is_ip6 = true;
-  return true;
-}
-
-static bool mg_aton6(struct mg_str str, struct mg_addr *addr) {
-  size_t i, j = 0, n = 0, dc = 42;
-  addr->scope_id = 0;
-  if (str.len > 2 && str.ptr[0] == '[') str.ptr++, str.len -= 2;
-  if (mg_v4mapped(str, addr)) return true;
-  for (i = 0; i < str.len; i++) {
-    if ((str.ptr[i] >= '0' && str.ptr[i] <= '9') ||
-        (str.ptr[i] >= 'a' && str.ptr[i] <= 'f') ||
-        (str.ptr[i] >= 'A' && str.ptr[i] <= 'F')) {
-      unsigned long val;
-      if (i > j + 3) return false;
-      // MG_DEBUG(("%lu %lu [%.*s]", i, j, (int) (i - j + 1), &str.ptr[j]));
-      val = mg_unhexn(&str.ptr[j], i - j + 1);
-      addr->ip[n] = (uint8_t) ((val >> 8) & 255);
-      addr->ip[n + 1] = (uint8_t) (val & 255);
-    } else if (str.ptr[i] == ':') {
-      j = i + 1;
-      if (i > 0 && str.ptr[i - 1] == ':') {
-        dc = n;  // Double colon
-        if (i > 1 && str.ptr[i - 2] == ':') return false;
-      } else if (i > 0) {
-        n += 2;
-      }
-      if (n > 14) return false;
-      addr->ip[n] = addr->ip[n + 1] = 0;  // For trailing ::
-    } else if (str.ptr[i] == '%') {       // Scope ID
-      for (i = i + 1; i < str.len; i++) {
-        if (str.ptr[i] < '0' || str.ptr[i] > '9') return false;
-        addr->scope_id *= 10, addr->scope_id += (uint8_t) (str.ptr[i] - '0');
-      }
-    } else {
-      return false;
-    }
-  }
-  if (n < 14 && dc == 42) return false;
-  if (n < 14) {
-    memmove(&addr->ip[dc + (14 - n)], &addr->ip[dc], n - dc + 2);
-    memset(&addr->ip[dc], 0, 14 - n);
-  }
-
-  addr->is_ip6 = true;
-  return true;
-}
-
-bool mg_aton(struct mg_str str, struct mg_addr *addr) {
-  // MG_INFO(("[%.*s]", (int) str.len, str.ptr));
-  return mg_atone(str, addr) || mg_atonl(str, addr) || mg_aton4(str, addr) ||
-         mg_aton6(str, addr);
-}
-
-struct mg_connection *mg_alloc_conn(struct mg_mgr *mgr) {
-  struct mg_connection *c =
-      (struct mg_connection *) calloc(1, sizeof(*c) + mgr->extraconnsize);
-  if (c != NULL) {
-    c->mgr = mgr;
-    c->send.align = c->recv.align = MG_IO_SIZE;
-    c->id = ++mgr->nextid;
-  }
-  return c;
-}
-
-void mg_close_conn(struct mg_connection *c) {
-  mg_resolve_cancel(c);  // Close any pending DNS query
-  LIST_DELETE(struct mg_connection, &c->mgr->conns, c);
-  if (c == c->mgr->dns4.c) c->mgr->dns4.c = NULL;
-  if (c == c->mgr->dns6.c) c->mgr->dns6.c = NULL;
-  // Order of operations is important. `MG_EV_CLOSE` event must be fired
-  // before we deallocate received data, see #1331
-  mg_call(c, MG_EV_CLOSE, NULL);
-  MG_DEBUG(("%lu %ld closed", c->id, c->fd));
-
-  mg_tls_free(c);
-  mg_iobuf_free(&c->recv);
-  mg_iobuf_free(&c->send);
-  mg_bzero((unsigned char *) c, sizeof(*c));
-  free(c);
-}
-
-struct mg_connection *mg_connect(struct mg_mgr *mgr, const char *url,
-                                 mg_event_handler_t fn, void *fn_data) {
-  struct mg_connection *c = NULL;
-  if (url == NULL || url[0] == '\0') {
-    MG_ERROR(("null url"));
-  } else if ((c = mg_alloc_conn(mgr)) == NULL) {
-    MG_ERROR(("OOM"));
-  } else {
-    LIST_ADD_HEAD(struct mg_connection, &mgr->conns, c);
-    c->is_udp = (strncmp(url, "udp:", 4) == 0);
-    c->fd = (void *) (size_t) MG_INVALID_SOCKET;
-    c->fn = fn;
-    c->is_client = true;
-    c->fn_data = fn_data;
-    MG_DEBUG(("%lu %ld %s", c->id, c->fd, url));
-    mg_call(c, MG_EV_OPEN, (void *) url);
-    mg_resolve(c, url);
-  }
-  return c;
-}
-
-struct mg_connection *mg_listen(struct mg_mgr *mgr, const char *url,
-                                mg_event_handler_t fn, void *fn_data) {
-  struct mg_connection *c = NULL;
-  if ((c = mg_alloc_conn(mgr)) == NULL) {
-    MG_ERROR(("OOM %s", url));
-  } else if (!mg_open_listener(c, url)) {
-    MG_ERROR(("Failed: %s, errno %d", url, errno));
-    free(c);
-    c = NULL;
-  } else {
-    c->is_listening = 1;
-    c->is_udp = strncmp(url, "udp:", 4) == 0;
-    LIST_ADD_HEAD(struct mg_connection, &mgr->conns, c);
-    c->fn = fn;
-    c->fn_data = fn_data;
-    mg_call(c, MG_EV_OPEN, NULL);
-    if (mg_url_is_ssl(url)) c->is_tls = 1;  // Accepted connection must
-    MG_DEBUG(("%lu %ld %s", c->id, c->fd, url));
-  }
-  return c;
-}
-
-struct mg_connection *mg_wrapfd(struct mg_mgr *mgr, int fd,
-                                mg_event_handler_t fn, void *fn_data) {
-  struct mg_connection *c = mg_alloc_conn(mgr);
-  if (c != NULL) {
-    c->fd = (void *) (size_t) fd;
-    c->fn = fn;
-    c->fn_data = fn_data;
-    MG_EPOLL_ADD(c);
-    mg_call(c, MG_EV_OPEN, NULL);
-    LIST_ADD_HEAD(struct mg_connection, &mgr->conns, c);
-  }
-  return c;
-}
-
-struct mg_timer *mg_timer_add(struct mg_mgr *mgr, uint64_t milliseconds,
-                              unsigned flags, void (*fn)(void *), void *arg) {
-  struct mg_timer *t = (struct mg_timer *) calloc(1, sizeof(*t));
-  if (t != NULL) {
-    mg_timer_init(&mgr->timers, t, milliseconds, flags, fn, arg);
-    t->id = mgr->timerid++;
-  }
-  return t;
-}
-
-void mg_mgr_free(struct mg_mgr *mgr) {
-  struct mg_connection *c;
-  struct mg_timer *tmp, *t = mgr->timers;
-  while (t != NULL) tmp = t->next, free(t), t = tmp;
-  mgr->timers = NULL;  // Important. Next call to poll won't touch timers
-  for (c = mgr->conns; c != NULL; c = c->next) c->is_closing = 1;
-  mg_mgr_poll(mgr, 0);
-#if MG_ENABLE_FREERTOS_TCP
-  FreeRTOS_DeleteSocketSet(mgr->ss);
-#endif
-  MG_DEBUG(("All connections closed"));
-#if MG_ENABLE_EPOLL
-  if (mgr->epoll_fd >= 0) close(mgr->epoll_fd), mgr->epoll_fd = -1;
-#endif
-  mg_tls_ctx_free(mgr);
-}
-
-void mg_mgr_init(struct mg_mgr *mgr) {
-  memset(mgr, 0, sizeof(*mgr));
-#if MG_ENABLE_EPOLL
-  if ((mgr->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
-    MG_ERROR(("epoll_create1 errno %d", errno));
-#else
-  mgr->epoll_fd = -1;
-#endif
-#if MG_ARCH == MG_ARCH_WIN32 && MG_ENABLE_WINSOCK
-  // clang-format off
-  { WSADATA data; WSAStartup(MAKEWORD(2, 2), &data); }
-  // clang-format on
-#elif MG_ENABLE_FREERTOS_TCP
-  mgr->ss = FreeRTOS_CreateSocketSet();
-#elif defined(__unix) || defined(__unix__) || defined(__APPLE__)
-  // Ignore SIGPIPE signal, so if client cancels the request, it
-  // won't kill the whole process.
-  signal(SIGPIPE, SIG_IGN);
-#endif
-  mgr->dnstimeout = 3000;
-  mgr->dns4.url = "udp://8.8.8.8:53";
-  mgr->dns6.url = "udp://[2001:4860:4860::8888]:53";
-  mg_tls_ctx_init(mgr);
-}
-
 #ifdef MG_ENABLE_LINES
 #line 1 "src/net_builtin.c"
 #endif
@@ -5263,147 +4996,414 @@ void mg_tcpip_init(struct mg_mgr *mgr, struct mg_tcpip_if *ifp) {
                                            // MG_EPHEMERAL_PORT_BASE to 65535
     if (ifp->tx.ptr == NULL || ifp->recv_queue.buf == NULL) MG_ERROR(("OOM"));
   }
-}
-
-void mg_tcpip_free(struct mg_tcpip_if *ifp) {
-  free(ifp->recv_queue.buf);
-  free((char *) ifp->tx.ptr);
-}
+}
+
+void mg_tcpip_free(struct mg_tcpip_if *ifp) {
+  free(ifp->recv_queue.buf);
+  free((char *) ifp->tx.ptr);
+}
+
+int mg_mkpipe(struct mg_mgr *m, mg_event_handler_t fn, void *d, bool udp) {
+  (void) m, (void) fn, (void) d, (void) udp;
+  MG_ERROR(("Not implemented"));
+  return -1;
+}
+
+static void send_syn(struct mg_connection *c) {
+  struct connstate *s = (struct connstate *) (c + 1);
+  uint32_t isn = mg_htonl((uint32_t) mg_ntohs(c->loc.port));
+  struct mg_tcpip_if *ifp = (struct mg_tcpip_if *) c->mgr->priv;
+  uint32_t rem_ip;
+  memcpy(&rem_ip, c->rem.ip, sizeof(uint32_t));
+  tx_tcp(ifp, s->mac, rem_ip, TH_SYN, c->loc.port, c->rem.port, isn, 0, NULL,
+         0);
+}
+
+void mg_connect_resolved(struct mg_connection *c) {
+  struct mg_tcpip_if *ifp = (struct mg_tcpip_if *) c->mgr->priv;
+  uint32_t rem_ip;
+  memcpy(&rem_ip, c->rem.ip, sizeof(uint32_t));
+  c->is_resolving = 0;
+  if (ifp->eport < MG_EPHEMERAL_PORT_BASE) ifp->eport = MG_EPHEMERAL_PORT_BASE;
+  memcpy(c->loc.ip, &ifp->ip, sizeof(uint32_t));
+  c->loc.port = mg_htons(ifp->eport++);
+  MG_DEBUG(("%lu %M -> %M", c->id, mg_print_ip_port, &c->loc, mg_print_ip_port,
+            &c->rem));
+  mg_call(c, MG_EV_RESOLVE, NULL);
+  if (c->is_udp && (rem_ip == 0xffffffff || rem_ip == (ifp->ip | ~ifp->mask))) {
+    struct connstate *s = (struct connstate *) (c + 1);
+    memset(s->mac, 0xFF, sizeof(s->mac));  // global or local broadcast
+  } else if (((rem_ip & ifp->mask) == (ifp->ip & ifp->mask))) {
+    // If we're in the same LAN, fire an ARP lookup.
+    MG_DEBUG(("%lu ARP lookup...", c->id));
+    arp_ask(ifp, rem_ip);
+    settmout(c, MIP_TTYPE_ARP);
+    c->is_arplooking = 1;
+    c->is_connecting = 1;
+  } else if ((*((uint8_t *) &rem_ip) & 0xE0) == 0xE0) {
+    struct connstate *s = (struct connstate *) (c + 1);  // 224 to 239, E0 to EF
+    uint8_t mcastp[3] = {0x01, 0x00, 0x5E};              // multicast group
+    memcpy(s->mac, mcastp, 3);
+    memcpy(s->mac + 3, ((uint8_t *) &rem_ip) + 1, 3);  // 23 LSb
+    s->mac[3] &= 0x7F;
+  } else {
+    struct connstate *s = (struct connstate *) (c + 1);
+    memcpy(s->mac, ifp->gwmac, sizeof(ifp->gwmac));
+    if (c->is_udp) {
+      mg_call(c, MG_EV_CONNECT, NULL);
+    } else {
+      send_syn(c);
+      settmout(c, MIP_TTYPE_SYN);
+      c->is_connecting = 1;
+    }
+  }
+}
+
+bool mg_open_listener(struct mg_connection *c, const char *url) {
+  c->loc.port = mg_htons(mg_url_port(url));
+  return true;
+}
+
+static void write_conn(struct mg_connection *c) {
+  long len = c->is_tls ? mg_tls_send(c, c->send.buf, c->send.len)
+                       : mg_io_send(c, c->send.buf, c->send.len);
+  if (len > 0) {
+    mg_iobuf_del(&c->send, 0, (size_t) len);
+    mg_call(c, MG_EV_WRITE, &len);
+  }
+}
+
+static void init_closure(struct mg_connection *c) {
+  struct connstate *s = (struct connstate *) (c + 1);
+  if (c->is_udp == false && c->is_listening == false &&
+      c->is_connecting == false) {  // For TCP conns,
+    struct mg_tcpip_if *ifp =
+        (struct mg_tcpip_if *) c->mgr->priv;  // send TCP FIN
+    uint32_t rem_ip;
+    memcpy(&rem_ip, c->rem.ip, sizeof(uint32_t));
+    tx_tcp(ifp, s->mac, rem_ip, TH_FIN | TH_ACK, c->loc.port, c->rem.port,
+           mg_htonl(s->seq), mg_htonl(s->ack), NULL, 0);
+    settmout(c, MIP_TTYPE_FIN);
+  }
+}
+
+static void close_conn(struct mg_connection *c) {
+  struct connstate *s = (struct connstate *) (c + 1);
+  mg_iobuf_free(&s->raw);  // For TLS connections, release raw data
+  mg_close_conn(c);
+}
+
+static bool can_write(struct mg_connection *c) {
+  return c->is_connecting == 0 && c->is_resolving == 0 && c->send.len > 0 &&
+         c->is_tls_hs == 0 && c->is_arplooking == 0;
+}
+
+void mg_mgr_poll(struct mg_mgr *mgr, int ms) {
+  struct mg_connection *c, *tmp;
+  uint64_t now = mg_millis();
+  mg_tcpip_poll((struct mg_tcpip_if *) mgr->priv, now);
+  mg_timer_poll(&mgr->timers, now);
+  for (c = mgr->conns; c != NULL; c = tmp) {
+    tmp = c->next;
+    struct connstate *s = (struct connstate *) (c + 1);
+    mg_call(c, MG_EV_POLL, &now);
+    MG_VERBOSE(("%lu .. %c%c%c%c%c", c->id, c->is_tls ? 'T' : 't',
+                c->is_connecting ? 'C' : 'c', c->is_tls_hs ? 'H' : 'h',
+                c->is_resolving ? 'R' : 'r', c->is_closing ? 'C' : 'c'));
+    if (c->is_tls_hs) mg_tls_handshake(c);
+    if (can_write(c)) write_conn(c);
+    if (c->is_draining && c->send.len == 0 && s->ttype != MIP_TTYPE_FIN)
+      init_closure(c);
+    if (c->is_closing) close_conn(c);
+  }
+  (void) ms;
+}
+
+bool mg_send(struct mg_connection *c, const void *buf, size_t len) {
+  struct mg_tcpip_if *ifp = (struct mg_tcpip_if *) c->mgr->priv;
+  bool res = false;
+  uint32_t rem_ip;
+  memcpy(&rem_ip, c->rem.ip, sizeof(uint32_t));
+  if (ifp->ip == 0 || ifp->state != MG_TCPIP_STATE_READY) {
+    mg_error(c, "net down");
+  } else if (c->is_udp) {
+    struct connstate *s = (struct connstate *) (c + 1);
+    len = trim_len(c, len);   // Trimming length if necessary
+    tx_udp(ifp, s->mac, ifp->ip, c->loc.port, rem_ip, c->rem.port, buf, len);
+    res = true;
+  } else {
+    res = mg_iobuf_add(&c->send, c->send.len, buf, len);
+  }
+  return res;
+}
+#endif  // MG_ENABLE_TCPIP
+
+#ifdef MG_ENABLE_LINES
+#line 1 "src/net.c"
+#endif
+
+
+
+
+
+
+
+
+size_t mg_vprintf(struct mg_connection *c, const char *fmt, va_list *ap) {
+  size_t old = c->send.len;
+  mg_vxprintf(mg_pfn_iobuf, &c->send, fmt, ap);
+  return c->send.len - old;
+}
+
+size_t mg_printf(struct mg_connection *c, const char *fmt, ...) {
+  size_t len = 0;
+  va_list ap;
+  va_start(ap, fmt);
+  len = mg_vprintf(c, fmt, &ap);
+  va_end(ap);
+  return len;
+}
+
+static bool mg_atonl(struct mg_str str, struct mg_addr *addr) {
+  uint32_t localhost = mg_htonl(0x7f000001);
+  if (mg_vcasecmp(&str, "localhost") != 0) return false;
+  memcpy(addr->ip, &localhost, sizeof(uint32_t));
+  addr->is_ip6 = false;
+  return true;
+}
+
+static bool mg_atone(struct mg_str str, struct mg_addr *addr) {
+  if (str.len > 0) return false;
+  memset(addr->ip, 0, sizeof(addr->ip));
+  addr->is_ip6 = false;
+  return true;
+}
+
+static bool mg_aton4(struct mg_str str, struct mg_addr *addr) {
+  uint8_t data[4] = {0, 0, 0, 0};
+  size_t i, num_dots = 0;
+  for (i = 0; i < str.len; i++) {
+    if (str.ptr[i] >= '0' && str.ptr[i] <= '9') {
+      int octet = data[num_dots] * 10 + (str.ptr[i] - '0');
+      if (octet > 255) return false;
+      data[num_dots] = (uint8_t) octet;
+    } else if (str.ptr[i] == '.') {
+      if (num_dots >= 3 || i == 0 || str.ptr[i - 1] == '.') return false;
+      num_dots++;
+    } else {
+      return false;
+    }
+  }
+  if (num_dots != 3 || str.ptr[i - 1] == '.') return false;
+  memcpy(&addr->ip, data, sizeof(data));
+  addr->is_ip6 = false;
+  return true;
+}
+
+static bool mg_v4mapped(struct mg_str str, struct mg_addr *addr) {
+  int i;
+  uint32_t ipv4;
+  if (str.len < 14) return false;
+  if (str.ptr[0] != ':' || str.ptr[1] != ':' || str.ptr[6] != ':') return false;
+  for (i = 2; i < 6; i++) {
+    if (str.ptr[i] != 'f' && str.ptr[i] != 'F') return false;
+  }
+  // struct mg_str s = mg_str_n(&str.ptr[7], str.len - 7);
+  if (!mg_aton4(mg_str_n(&str.ptr[7], str.len - 7), addr)) return false;
+  memcpy(&ipv4, addr->ip, sizeof(ipv4));
+  memset(addr->ip, 0, sizeof(addr->ip));
+  addr->ip[10] = addr->ip[11] = 255;
+  memcpy(&addr->ip[12], &ipv4, 4);
+  addr->is_ip6 = true;
+  return true;
+}
+
+static bool mg_aton6(struct mg_str str, struct mg_addr *addr) {
+  size_t i, j = 0, n = 0, dc = 42;
+  addr->scope_id = 0;
+  if (str.len > 2 && str.ptr[0] == '[') str.ptr++, str.len -= 2;
+  if (mg_v4mapped(str, addr)) return true;
+  for (i = 0; i < str.len; i++) {
+    if ((str.ptr[i] >= '0' && str.ptr[i] <= '9') ||
+        (str.ptr[i] >= 'a' && str.ptr[i] <= 'f') ||
+        (str.ptr[i] >= 'A' && str.ptr[i] <= 'F')) {
+      unsigned long val;
+      if (i > j + 3) return false;
+      // MG_DEBUG(("%lu %lu [%.*s]", i, j, (int) (i - j + 1), &str.ptr[j]));
+      val = mg_unhexn(&str.ptr[j], i - j + 1);
+      addr->ip[n] = (uint8_t) ((val >> 8) & 255);
+      addr->ip[n + 1] = (uint8_t) (val & 255);
+    } else if (str.ptr[i] == ':') {
+      j = i + 1;
+      if (i > 0 && str.ptr[i - 1] == ':') {
+        dc = n;  // Double colon
+        if (i > 1 && str.ptr[i - 2] == ':') return false;
+      } else if (i > 0) {
+        n += 2;
+      }
+      if (n > 14) return false;
+      addr->ip[n] = addr->ip[n + 1] = 0;  // For trailing ::
+    } else if (str.ptr[i] == '%') {       // Scope ID
+      for (i = i + 1; i < str.len; i++) {
+        if (str.ptr[i] < '0' || str.ptr[i] > '9') return false;
+        addr->scope_id *= 10, addr->scope_id += (uint8_t) (str.ptr[i] - '0');
+      }
+    } else {
+      return false;
+    }
+  }
+  if (n < 14 && dc == 42) return false;
+  if (n < 14) {
+    memmove(&addr->ip[dc + (14 - n)], &addr->ip[dc], n - dc + 2);
+    memset(&addr->ip[dc], 0, 14 - n);
+  }
 
-int mg_mkpipe(struct mg_mgr *m, mg_event_handler_t fn, void *d, bool udp) {
-  (void) m, (void) fn, (void) d, (void) udp;
-  MG_ERROR(("Not implemented"));
-  return -1;
+  addr->is_ip6 = true;
+  return true;
 }
 
-static void send_syn(struct mg_connection *c) {
-  struct connstate *s = (struct connstate *) (c + 1);
-  uint32_t isn = mg_htonl((uint32_t) mg_ntohs(c->loc.port));
-  struct mg_tcpip_if *ifp = (struct mg_tcpip_if *) c->mgr->priv;
-  uint32_t rem_ip;
-  memcpy(&rem_ip, c->rem.ip, sizeof(uint32_t));
-  tx_tcp(ifp, s->mac, rem_ip, TH_SYN, c->loc.port, c->rem.port, isn, 0, NULL,
-         0);
+bool mg_aton(struct mg_str str, struct mg_addr *addr) {
+  // MG_INFO(("[%.*s]", (int) str.len, str.ptr));
+  return mg_atone(str, addr) || mg_atonl(str, addr) || mg_aton4(str, addr) ||
+         mg_aton6(str, addr);
 }
 
-void mg_connect_resolved(struct mg_connection *c) {
-  struct mg_tcpip_if *ifp = (struct mg_tcpip_if *) c->mgr->priv;
-  uint32_t rem_ip;
-  memcpy(&rem_ip, c->rem.ip, sizeof(uint32_t));
-  c->is_resolving = 0;
-  if (ifp->eport < MG_EPHEMERAL_PORT_BASE) ifp->eport = MG_EPHEMERAL_PORT_BASE;
-  memcpy(c->loc.ip, &ifp->ip, sizeof(uint32_t));
-  c->loc.port = mg_htons(ifp->eport++);
-  MG_DEBUG(("%lu %M -> %M", c->id, mg_print_ip_port, &c->loc, mg_print_ip_port,
-            &c->rem));
-  mg_call(c, MG_EV_RESOLVE, NULL);
-  if (c->is_udp && (rem_ip == 0xffffffff || rem_ip == (ifp->ip | ~ifp->mask))) {
-    struct connstate *s = (struct connstate *) (c + 1);
-    memset(s->mac, 0xFF, sizeof(s->mac));  // global or local broadcast
-  } else if (((rem_ip & ifp->mask) == (ifp->ip & ifp->mask))) {
-    // If we're in the same LAN, fire an ARP lookup.
-    MG_DEBUG(("%lu ARP lookup...", c->id));
-    arp_ask(ifp, rem_ip);
-    settmout(c, MIP_TTYPE_ARP);
-    c->is_arplooking = 1;
-    c->is_connecting = 1;
-  } else if ((*((uint8_t *) &rem_ip) & 0xE0) == 0xE0) {
-    struct connstate *s = (struct connstate *) (c + 1);  // 224 to 239, E0 to EF
-    uint8_t mcastp[3] = {0x01, 0x00, 0x5E};              // multicast group
-    memcpy(s->mac, mcastp, 3);
-    memcpy(s->mac + 3, ((uint8_t *) &rem_ip) + 1, 3);  // 23 LSb
-    s->mac[3] &= 0x7F;
-  } else {
-    struct connstate *s = (struct connstate *) (c + 1);
-    memcpy(s->mac, ifp->gwmac, sizeof(ifp->gwmac));
-    if (c->is_udp) {
-      mg_call(c, MG_EV_CONNECT, NULL);
-    } else {
-      send_syn(c);
-      settmout(c, MIP_TTYPE_SYN);
-      c->is_connecting = 1;
-    }
+struct mg_connection *mg_alloc_conn(struct mg_mgr *mgr) {
+  struct mg_connection *c =
+      (struct mg_connection *) calloc(1, sizeof(*c) + mgr->extraconnsize);
+  if (c != NULL) {
+    c->mgr = mgr;
+    c->send.align = c->recv.align = MG_IO_SIZE;
+    c->id = ++mgr->nextid;
   }
+  return c;
 }
 
-bool mg_open_listener(struct mg_connection *c, const char *url) {
-  c->loc.port = mg_htons(mg_url_port(url));
-  return true;
+void mg_close_conn(struct mg_connection *c) {
+  mg_resolve_cancel(c);  // Close any pending DNS query
+  LIST_DELETE(struct mg_connection, &c->mgr->conns, c);
+  if (c == c->mgr->dns4.c) c->mgr->dns4.c = NULL;
+  if (c == c->mgr->dns6.c) c->mgr->dns6.c = NULL;
+  // Order of operations is important. `MG_EV_CLOSE` event must be fired
+  // before we deallocate received data, see #1331
+  mg_call(c, MG_EV_CLOSE, NULL);
+  MG_DEBUG(("%lu %ld closed", c->id, c->fd));
+
+  mg_tls_free(c);
+  mg_iobuf_free(&c->recv);
+  mg_iobuf_free(&c->send);
+  mg_bzero((unsigned char *) c, sizeof(*c));
+  free(c);
 }
 
-static void write_conn(struct mg_connection *c) {
-  long len = c->is_tls ? mg_tls_send(c, c->send.buf, c->send.len)
-                       : mg_io_send(c, c->send.buf, c->send.len);
-  if (len > 0) {
-    mg_iobuf_del(&c->send, 0, (size_t) len);
-    mg_call(c, MG_EV_WRITE, &len);
+struct mg_connection *mg_connect(struct mg_mgr *mgr, const char *url,
+                                 mg_event_handler_t fn, void *fn_data) {
+  struct mg_connection *c = NULL;
+  if (url == NULL || url[0] == '\0') {
+    MG_ERROR(("null url"));
+  } else if ((c = mg_alloc_conn(mgr)) == NULL) {
+    MG_ERROR(("OOM"));
+  } else {
+    LIST_ADD_HEAD(struct mg_connection, &mgr->conns, c);
+    c->is_udp = (strncmp(url, "udp:", 4) == 0);
+    c->fd = (void *) (size_t) MG_INVALID_SOCKET;
+    c->fn = fn;
+    c->is_client = true;
+    c->fn_data = fn_data;
+    MG_DEBUG(("%lu %ld %s", c->id, c->fd, url));
+    mg_call(c, MG_EV_OPEN, (void *) url);
+    mg_resolve(c, url);
   }
+  return c;
 }
 
-static void init_closure(struct mg_connection *c) {
-  struct connstate *s = (struct connstate *) (c + 1);
-  if (c->is_udp == false && c->is_listening == false &&
-      c->is_connecting == false) {  // For TCP conns,
-    struct mg_tcpip_if *ifp =
-        (struct mg_tcpip_if *) c->mgr->priv;  // send TCP FIN
-    uint32_t rem_ip;
-    memcpy(&rem_ip, c->rem.ip, sizeof(uint32_t));
-    tx_tcp(ifp, s->mac, rem_ip, TH_FIN | TH_ACK, c->loc.port, c->rem.port,
-           mg_htonl(s->seq), mg_htonl(s->ack), NULL, 0);
-    settmout(c, MIP_TTYPE_FIN);
+struct mg_connection *mg_listen(struct mg_mgr *mgr, const char *url,
+                                mg_event_handler_t fn, void *fn_data) {
+  struct mg_connection *c = NULL;
+  if ((c = mg_alloc_conn(mgr)) == NULL) {
+    MG_ERROR(("OOM %s", url));
+  } else if (!mg_open_listener(c, url)) {
+    MG_ERROR(("Failed: %s, errno %d", url, errno));
+    free(c);
+    c = NULL;
+  } else {
+    c->is_listening = 1;
+    c->is_udp = strncmp(url, "udp:", 4) == 0;
+    LIST_ADD_HEAD(struct mg_connection, &mgr->conns, c);
+    c->fn = fn;
+    c->fn_data = fn_data;
+    mg_call(c, MG_EV_OPEN, NULL);
+    if (mg_url_is_ssl(url)) c->is_tls = 1;  // Accepted connection must
+    MG_DEBUG(("%lu %ld %s", c->id, c->fd, url));
   }
+  return c;
 }
 
-static void close_conn(struct mg_connection *c) {
-  struct connstate *s = (struct connstate *) (c + 1);
-  mg_iobuf_free(&s->raw);  // For TLS connections, release raw data
-  mg_close_conn(c);
+struct mg_connection *mg_wrapfd(struct mg_mgr *mgr, int fd,
+                                mg_event_handler_t fn, void *fn_data) {
+  struct mg_connection *c = mg_alloc_conn(mgr);
+  if (c != NULL) {
+    c->fd = (void *) (size_t) fd;
+    c->fn = fn;
+    c->fn_data = fn_data;
+    MG_EPOLL_ADD(c);
+    mg_call(c, MG_EV_OPEN, NULL);
+    LIST_ADD_HEAD(struct mg_connection, &mgr->conns, c);
+  }
+  return c;
 }
 
-static bool can_write(struct mg_connection *c) {
-  return c->is_connecting == 0 && c->is_resolving == 0 && c->send.len > 0 &&
-         c->is_tls_hs == 0 && c->is_arplooking == 0;
+struct mg_timer *mg_timer_add(struct mg_mgr *mgr, uint64_t milliseconds,
+                              unsigned flags, void (*fn)(void *), void *arg) {
+  struct mg_timer *t = (struct mg_timer *) calloc(1, sizeof(*t));
+  if (t != NULL) {
+    mg_timer_init(&mgr->timers, t, milliseconds, flags, fn, arg);
+    t->id = mgr->timerid++;
+  }
+  return t;
 }
 
-void mg_mgr_poll(struct mg_mgr *mgr, int ms) {
-  struct mg_connection *c, *tmp;
-  uint64_t now = mg_millis();
-  mg_tcpip_poll((struct mg_tcpip_if *) mgr->priv, now);
-  mg_timer_poll(&mgr->timers, now);
-  for (c = mgr->conns; c != NULL; c = tmp) {
-    tmp = c->next;
-    struct connstate *s = (struct connstate *) (c + 1);
-    mg_call(c, MG_EV_POLL, &now);
-    MG_VERBOSE(("%lu .. %c%c%c%c%c", c->id, c->is_tls ? 'T' : 't',
-                c->is_connecting ? 'C' : 'c', c->is_tls_hs ? 'H' : 'h',
-                c->is_resolving ? 'R' : 'r', c->is_closing ? 'C' : 'c'));
-    if (c->is_tls_hs) mg_tls_handshake(c);
-    if (can_write(c)) write_conn(c);
-    if (c->is_draining && c->send.len == 0 && s->ttype != MIP_TTYPE_FIN)
-      init_closure(c);
-    if (c->is_closing) close_conn(c);
-  }
-  (void) ms;
+void mg_mgr_free(struct mg_mgr *mgr) {
+  struct mg_connection *c;
+  struct mg_timer *tmp, *t = mgr->timers;
+  while (t != NULL) tmp = t->next, free(t), t = tmp;
+  mgr->timers = NULL;  // Important. Next call to poll won't touch timers
+  for (c = mgr->conns; c != NULL; c = c->next) c->is_closing = 1;
+  mg_mgr_poll(mgr, 0);
+#if MG_ENABLE_FREERTOS_TCP
+  FreeRTOS_DeleteSocketSet(mgr->ss);
+#endif
+  MG_DEBUG(("All connections closed"));
+#if MG_ENABLE_EPOLL
+  if (mgr->epoll_fd >= 0) close(mgr->epoll_fd), mgr->epoll_fd = -1;
+#endif
+  mg_tls_ctx_free(mgr);
 }
 
-bool mg_send(struct mg_connection *c, const void *buf, size_t len) {
-  struct mg_tcpip_if *ifp = (struct mg_tcpip_if *) c->mgr->priv;
-  bool res = false;
-  uint32_t rem_ip;
-  memcpy(&rem_ip, c->rem.ip, sizeof(uint32_t));
-  if (ifp->ip == 0 || ifp->state != MG_TCPIP_STATE_READY) {
-    mg_error(c, "net down");
-  } else if (c->is_udp) {
-    struct connstate *s = (struct connstate *) (c + 1);
-    len = trim_len(c, len);   // Trimming length if necessary
-    tx_udp(ifp, s->mac, ifp->ip, c->loc.port, rem_ip, c->rem.port, buf, len);
-    res = true;
-  } else {
-    res = mg_iobuf_add(&c->send, c->send.len, buf, len);
-  }
-  return res;
+void mg_mgr_init(struct mg_mgr *mgr) {
+  memset(mgr, 0, sizeof(*mgr));
+#if MG_ENABLE_EPOLL
+  if ((mgr->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
+    MG_ERROR(("epoll_create1 errno %d", errno));
+#else
+  mgr->epoll_fd = -1;
+#endif
+#if MG_ARCH == MG_ARCH_WIN32 && MG_ENABLE_WINSOCK
+  // clang-format off
+  { WSADATA data; WSAStartup(MAKEWORD(2, 2), &data); }
+  // clang-format on
+#elif MG_ENABLE_FREERTOS_TCP
+  mgr->ss = FreeRTOS_CreateSocketSet();
+#elif defined(__unix) || defined(__unix__) || defined(__APPLE__)
+  // Ignore SIGPIPE signal, so if client cancels the request, it
+  // won't kill the whole process.
+  signal(SIGPIPE, SIG_IGN);
+#endif
+  mgr->dnstimeout = 3000;
+  mgr->dns4.url = "udp://8.8.8.8:53";
+  mgr->dns6.url = "udp://[2001:4860:4860::8888]:53";
+  mg_tls_ctx_init(mgr);
 }
-#endif  // MG_ENABLE_TCPIP
 
 #ifdef MG_ENABLE_LINES
 #line 1 "src/ota_dummy.c"
@@ -8488,9 +8488,9 @@ typedef struct enet_bd_struct_def
 } enet_bd_struct_t;
 
 // Descriptor and buffer globals, in non-cached area, 64 bits aligned.
-
-__attribute__((section("NonCacheable,\"aw\",%nobits @"))) enet_bd_struct_t rx_buffer_descriptor[(ENET_RXBD_NUM)] __attribute__((aligned((64U))));
-__attribute__((section("NonCacheable,\"aw\",%nobits @"))) enet_bd_struct_t tx_buffer_descriptor[(ENET_TXBD_NUM)] __attribute__((aligned((64U))));
+// TODO(): handle these in a portable compiler-independent CMSIS-friendly way
+/*__attribute__((section("NonCacheable,\"aw\",%nobits @")))*/ enet_bd_struct_t rx_buffer_descriptor[(ENET_RXBD_NUM)] __attribute__((aligned((64U))));
+/*__attribute__((section("NonCacheable,\"aw\",%nobits @")))*/ enet_bd_struct_t tx_buffer_descriptor[(ENET_TXBD_NUM)] __attribute__((aligned((64U))));
 
 uint8_t rx_data_buffer[(ENET_RXBD_NUM)][((unsigned int)(((ENET_RXBUFF_SIZE)) + (((64U))-1U)) & (unsigned int)(~(unsigned int)(((64U))-1U)))] __attribute__((aligned((64U))));
 uint8_t tx_data_buffer[(ENET_TXBD_NUM)][((unsigned int)(((ENET_TXBUFF_SIZE)) + (((64U))-1U)) & (unsigned int)(~(unsigned int)(((64U))-1U)))] __attribute__((aligned((64U))));
@@ -8500,7 +8500,7 @@ uint8_t tx_data_buffer[(ENET_TXBD_NUM)][((unsigned int)(((ENET_TXBUFF_SIZE)) + (
 // static bool mg_tcpip_driver_imxrt1020_init(uint8_t *mac, void *data) { // VO
 static bool mg_tcpip_driver_imxrt1020_init(struct mg_tcpip_if *ifp) {
 
-  struct mg_tcpip_driver_imxrt1020_data *d = (struct mg_tcpip_driver_imxrt1020_data *) ifp->driver_data;
+// TODO(scaprile):  struct mg_tcpip_driver_imxrt1020_data *d = (struct mg_tcpip_driver_imxrt1020_data *) ifp->driver_data;
   s_ifp = ifp;
 
   // ENET Reset, wait complete
@@ -8531,6 +8531,7 @@ static bool mg_tcpip_driver_imxrt1020_init(struct mg_tcpip_if *ifp) {
 
   // Configure ENET
   ENET->RCR = 0x05ee0104; // #CRCFWD=0 (CRC kept in frame) + RMII + MII Enable
+  //ENET->RCR |= BIT(3);                            // Receive all
   
   ENET->TCR = BIT(8) | BIT(2); // Addins (MAC address from PAUR+PALR) + Full duplex enable
   //ENET->TFWR = BIT(8); // Store And Forward Enable, 64 bytes (minimize tx latency)
diff --git a/mongoose.h b/mongoose.h
index 9cb4d30628..ab251ffb57 100644
--- a/mongoose.h
+++ b/mongoose.h
@@ -1784,7 +1784,7 @@ extern struct mg_tcpip_driver mg_tcpip_driver_stm32;
 extern struct mg_tcpip_driver mg_tcpip_driver_w5500;
 extern struct mg_tcpip_driver mg_tcpip_driver_tm4c;
 extern struct mg_tcpip_driver mg_tcpip_driver_stm32h;
-extern struct mg_tcpip_driver mg_tcpip_driver_imxrt;
+extern struct mg_tcpip_driver mg_tcpip_driver_imxrt1020;
 extern struct mg_tcpip_driver mg_tcpip_driver_same54;
 
 // Drivers that require SPI, can use this SPI abstraction
diff --git a/src/drivers/rt1020.c b/src/drivers/rt1020.c
index 7eaec4a525..363fd912f1 100644
--- a/src/drivers/rt1020.c
+++ b/src/drivers/rt1020.c
@@ -97,9 +97,9 @@ typedef struct enet_bd_struct_def
 } enet_bd_struct_t;
 
 // Descriptor and buffer globals, in non-cached area, 64 bits aligned.
-
-__attribute__((section("NonCacheable,\"aw\",%nobits @"))) enet_bd_struct_t rx_buffer_descriptor[(ENET_RXBD_NUM)] __attribute__((aligned((64U))));
-__attribute__((section("NonCacheable,\"aw\",%nobits @"))) enet_bd_struct_t tx_buffer_descriptor[(ENET_TXBD_NUM)] __attribute__((aligned((64U))));
+// TODO(): handle these in a portable compiler-independent CMSIS-friendly way
+/*__attribute__((section("NonCacheable,\"aw\",%nobits @")))*/ enet_bd_struct_t rx_buffer_descriptor[(ENET_RXBD_NUM)] __attribute__((aligned((64U))));
+/*__attribute__((section("NonCacheable,\"aw\",%nobits @")))*/ enet_bd_struct_t tx_buffer_descriptor[(ENET_TXBD_NUM)] __attribute__((aligned((64U))));
 
 uint8_t rx_data_buffer[(ENET_RXBD_NUM)][((unsigned int)(((ENET_RXBUFF_SIZE)) + (((64U))-1U)) & (unsigned int)(~(unsigned int)(((64U))-1U)))] __attribute__((aligned((64U))));
 uint8_t tx_data_buffer[(ENET_TXBD_NUM)][((unsigned int)(((ENET_TXBUFF_SIZE)) + (((64U))-1U)) & (unsigned int)(~(unsigned int)(((64U))-1U)))] __attribute__((aligned((64U))));
@@ -109,7 +109,7 @@ uint8_t tx_data_buffer[(ENET_TXBD_NUM)][((unsigned int)(((ENET_TXBUFF_SIZE)) + (
 // static bool mg_tcpip_driver_imxrt1020_init(uint8_t *mac, void *data) { // VO
 static bool mg_tcpip_driver_imxrt1020_init(struct mg_tcpip_if *ifp) {
 
-  struct mg_tcpip_driver_imxrt1020_data *d = (struct mg_tcpip_driver_imxrt1020_data *) ifp->driver_data;
+// TODO(scaprile):  struct mg_tcpip_driver_imxrt1020_data *d = (struct mg_tcpip_driver_imxrt1020_data *) ifp->driver_data;
   s_ifp = ifp;
 
   // ENET Reset, wait complete
@@ -140,6 +140,7 @@ static bool mg_tcpip_driver_imxrt1020_init(struct mg_tcpip_if *ifp) {
 
   // Configure ENET
   ENET->RCR = 0x05ee0104; // #CRCFWD=0 (CRC kept in frame) + RMII + MII Enable
+  //ENET->RCR |= BIT(3);                            // Receive all
   
   ENET->TCR = BIT(8) | BIT(2); // Addins (MAC address from PAUR+PALR) + Full duplex enable
   //ENET->TFWR = BIT(8); // Store And Forward Enable, 64 bytes (minimize tx latency)
diff --git a/src/net_builtin.h b/src/net_builtin.h
index 5cc412df4a..4ea2346dbe 100644
--- a/src/net_builtin.h
+++ b/src/net_builtin.h
@@ -55,7 +55,7 @@ extern struct mg_tcpip_driver mg_tcpip_driver_stm32;
 extern struct mg_tcpip_driver mg_tcpip_driver_w5500;
 extern struct mg_tcpip_driver mg_tcpip_driver_tm4c;
 extern struct mg_tcpip_driver mg_tcpip_driver_stm32h;
-extern struct mg_tcpip_driver mg_tcpip_driver_imxrt;
+extern struct mg_tcpip_driver mg_tcpip_driver_imxrt1020;
 extern struct mg_tcpip_driver mg_tcpip_driver_same54;
 
 // Drivers that require SPI, can use this SPI abstraction