To: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
From: Dan Libby <dan@osc.co.cr>
Message-ID: <9e212eae-08d5-d083-80d9-a8e29679fcdc@osc.co.cr>
Date: Wed, 13 Sep 2017 02:50:53 -0700
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Subject: [bitcoin-dev] hypothetical: Could soft-forks be prevented?
Precedence: list

Hi, I am interested in the possibility of a cryptocurrency software
(future bitcoin or a future altcoin) that strives to have immutable
consensus rules.

The goal of such a cryptocurrency would not be to have the latest and
greatest tech, but rather to be a long-term store of value and to offer
investors great certainty and predictability... something that markets
tend to like.  And of course, zero consensus rule changes also means
less chance of new bugs and attack surface remains the same, which is
good for security.

Of course, hard-forks are always possible.  But that is a clear split
and something that people must opt into.  Each party has to make a
choice, and inertia is on the side of the status quo.  Whereas
soft-forks sort of drag people along with them, even those who oppose
the changes and never upgrade.  In my view, that is problematic,
especially for a coin with permanent consensus rule immutability as a
goal/ethic.

As I understand it, bitcoin soft-forks always rely on anyone-can-spend
transactions.  If those were removed, would it effectively prevent
soft-forks, or are there other possible mechanisms?  How important are
any-one-can spend tx for other uses?

More generally, do you think it is possible to programmatically
avoid/ban soft-forks, and if so, how would you go about it?