Imagine my disappointment after working on a fixed-allocation HTTP server stack to discover that even `esp_log.h` does several malloc() calls [1] per log output line... thankfully that was only on the ESP8266_RTOS_SDK, and esp-idf isn't quite as bad.

[1] https://github.com/espressif/ESP8266_RTOS_SDK/blob/89a3f254b...