Since previously released version - 0.3.0 - 107 days have passed, while 431 commits appeared in the repository, so it's clearly high time for a new release! Therefore, today I have published fourth version of the C++ RTOS for microcontrollers - distortos 0.4.0. Thanks to adding support for the whole STM32F7 chip family (along with 32F746GDISCOVERY board), total number of supported chips has risen to 395. Other new features especially worth mentioning are two options (each in two variants) which enable run-time stack overflow detection and an option which enables context checking of functions which must not be used from interrupts (all blocking functions, all functions of Mutex class and all functions from ThisThread namespace). These last two additions allow for detection of the most frequent problems which are encountered by developers of multithreaded embedded applications, which are otherwise very hard to track - I've had the opportunity to find that out more than once. Quite recently I was completely shocked to learn (thanks to one of these new options) that developers of ST's USB libraries don't have even the slightest objections at all to happily allocate dynamic memory in interrupts...