MCUboot now part of the west manifest
MCUboot is now part of the upstream Zephyr manifest. We maintain a mirror of MCUboot, which serves as the current reference version that is tested with Zephry, here:
If you take the latest master and run 'west update' on it you will find MCUboot in bootloaders/mcuboot.
MCUboot is also built by CI on every Pull Request, and that should help alleviate the compatibility problems between Zephyr and MCUboot that have often appeared in the past.