I can't second that recommendation enough. Any db migration project that uses sequence numbers to label/sort migrations is badly broken for any team larger than 1.
I've used enough of these migration systems now that I'm convinced any system using sequence numbers likely has other, less noticeable problems since the problem space is complex and this is a known best practice of which the developers somehow remained ignorant.
I've used enough of these migration systems now that I'm convinced any system using sequence numbers likely has other, less noticeable problems since the problem space is complex and this is a known best practice of which the developers somehow remained ignorant.