my $new_head = make_commit [ $old_head, $ffq_prev ], [
'Declare fast forward / record previous work',
"[git-debrebase pseudomerge: $prose]",
my $new_head = make_commit [ $old_head, $ffq_prev ], [
'Declare fast forward / record previous work',
"[git-debrebase pseudomerge: $prose]",