I hope you don't mind me removing a few bytes: 

sub f{for(values(%h=@_)){$h{$_}||=[]for@$_}sort{(grep/^$b$/,@{$h{$a}})
+||-1}keys%h}

[download]
(Note: I didn't test) 

U28geW91IGNhbiBhbGwgcm90MTMgY
W5kIHBhY2soKS4gQnV0IGRvIHlvdS
ByZWNvZ25pc2UgQmFzZTY0IHdoZW4
geW91IHNlZSBpdD8gIC0tIEp1ZXJk

In reply to Re: Re: Re: (Golf) Dependency List Prioritization by Juerd
in thread (Golf) Dependency List Prioritization by tadman

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