He had modified the ramdisk of recovery, he did not build it from source.
Are you really sure about that? I'd like to have access to the source as well, but according to
http://www.internauta37.altervista.org/en/xt894-and-xt912-safestrap-375-unused-partitions-preinstall-webtop
he integrated some changes:
This version of SafeStrap is based on SafeStrap 3.75 but has a lot of differences with it:
- there is not more the splashscreen during the boot, to enter in Safestrap you have to select BP Tools in the Boot Mode Selection Menu(VolUp&&VolDown+PowerOn)
- has been added a Safe Rom slot that uses the unused partitions: /preinstall for /system; /webtop for /data; /cache is shared with the Stock Rom slot
- in this version you have 6 slots: the Stock Rom slot, the Safe Rom slot and the four virtual slots
Or am I wrong?