diff --git a/src/nimble/porting/npl/freertos/include/nimble/nimble_npl_os.h b/src/nimble/porting/npl/freertos/include/nimble/nimble_npl_os.h
index 2624abfb..d23f474f 100644
--- a/src/nimble/porting/npl/freertos/include/nimble/nimble_npl_os.h
+++ b/src/nimble/porting/npl/freertos/include/nimble/nimble_npl_os.h
@@ -422,6 +422,9 @@ static inline bool ble_npl_hw_is_in_critical(void)
 #include "freertos/semphr.h"
 #include "freertos/task.h"
 #include "freertos/timers.h"
+#ifdef CONFIG_BT_NIMBLE_USE_ESP_TIMER
+#include "esp_timer.h"
+#endif
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/src/nimconfig.h b/src/nimconfig.h
index fb48423f..56dace2e 100644
--- a/src/nimconfig.h
+++ b/src/nimconfig.h
@@ -165,6 +165,12 @@
  */
 // #define CONFIG_NIMBLE_CPP_ADDR_FMT_UPPERCASE 1
 
+/**
+ * @brief Un-comment to use mbedtls instead of tinycrypt.
+ * @details This could save approximately 8k of flash if already using mbedtls for other functionality.
+ */
+// #define CONFIG_BT_NIMBLE_CRYPTO_STACK_MBEDTLS 1
+
 /**********************************
  End Arduino user-config
 **********************************/
@@ -291,6 +297,14 @@
 #define CONFIG_BT_CONTROLLER_ENABLED 1
 #endif
 
+#ifndef CONFIG_BT_NIMBLE_CRYPTO_STACK_MBEDTLS
+#define CONFIG_BT_NIMBLE_CRYPTO_STACK_MBEDTLS 0
+#endif
+
+#ifndef MYNEWT_VAL_BLE_CRYPTO_STACK_MBEDTLS
+#define MYNEWT_VAL_BLE_CRYPTO_STACK_MBEDTLS (CONFIG_BT_NIMBLE_CRYPTO_STACK_MBEDTLS)
+#endif
+
 #ifdef ESP_PLATFORM
 #ifndef CONFIG_BTDM_CONTROLLER_MODE_BLE_ONLY
 #define CONFIG_BTDM_CONTROLLER_MODE_BLE_ONLY
@@ -325,6 +339,11 @@
 #    error Extended advertising is not supported on ESP32.
 #  endif
 #endif
+
+#ifndef CONFIG_BT_NIMBLE_USE_ESP_TIMER
+#define CONFIG_BT_NIMBLE_USE_ESP_TIMER 1
+#endif
+
 #endif // ESP_PLATFORM
 
 #if CONFIG_BT_NIMBLE_ENABLE_PERIODIC_ADV && !CONFIG_BT_NIMBLE_EXT_ADV