First-seen-safe Replace-by-Fee is now available as a patch against
v0.10.2:

    https://github.com/petertodd/bitcoin/tree/first-seen-safe-rbf-v0.10.2

I've also had a pull-req against git HEAD open for a few weeks now:

    https://github.com/bitcoin/bitcoin/pull/6176#issuecomment-104877829

I've got some hashing power interested in running this patch in the near
future, so I'm offering a bounty of up to 1 BTC to anyone who can find a
way to attack miners running this patch. Specifically, I'm concerned
about things that would lead to significant losses for those miners. A
total crash would be considered very serious - 1 BTC - while excess
bandwidth usage would be considered minor - more like 0.1 BTC. (remember
that this would have to be bandwidth significantly in excess of existing
attacks)

For reference, here's an example of a crash exploit found by Suhas
Daftuar: https://github.com/bitcoin/bitcoin/pull/6176#issuecomment-104877829

If two people report the same or overlapping issues, first person will
get priority. Adding a new test that demos your exploit to the unit
tests will be looked upon favorably. That said, in general I'm not going
to make any hard promises with regards to payouts and will be using my
best judgement. I've got a bit over 2BTC budgetted for this, which is
coming out of my own pockets - I'm not rich! All applicants are however
welcome to troll me on reddit if you think I'm being unfair.


Suhas: speaking of, feel free to email me a Bitcoin address! :)

-- 
'peter'[:-1]@petertodd.org
000000000000000006dd456cf5ff8bbb56cf88e9314711d55b75c8d23cccddd5