[Cpoll]

> how do you vet that

One of the maxims of security is that a sufficiently determined and resourceful attacker will always win. The defender's job is to disincentivize the attacker.

However, I think for a sufficiently high-impact project no-one should have commit access, every commit should be reviewed by quorum. Even so, you still run into "Underhanded C"-style stuff (and disinterested reviewers), and you still need to vet the quorum.