Andresen Considering Shift to Bitcoin-Xt

In the latest development on the debate about the potential increase of the 1-megabyte block size limit, Gavin Andressen (Core developer, Bitcoin Foundation and MIT Digital Currency Initiative) expressed the possibility of moving forward with his proposed changes on the Bitcoin-XT project (authored by Mike Hearn, more information below the e-mails), in a chain of e-mails within the Bitcoin developers mailing list:


What do other people think?


If we can’t come to an agreement soon, then I’ll ask for help

reviewing/submitting patches to Mike’s Bitcoin-Xt project that implement a

big increase now that grows over time so we may never have to go through

all this rancor and debate again.


I’ll then ask for help lobbying the merchant services and exchanges and

hosted wallet companies and other bitcoind-using-infrastructure companies

(and anybody who agrees with me that we need bigger blocks sooner rather

than later) to run Bitcoin-Xt instead of Bitcoin Core, and state that they

are running it. We’ll be able to see uptake on the network by monitoring

client versions.


Perhaps by the time that happens there will be consensus bigger blocks are

needed sooner rather than later; if so, great! The early deployment will

just serve as early testing, and all of the software already deployed will

ready for bigger blocks.


But if there is still no consensus among developers but the “bigger blocks

now” movement is successful, I’ll ask for help getting big miners to do the

same, and use the soft-fork block version voting mechanism to (hopefully)

get a majority and then a super-majority willing to produce bigger blocks.

The purpose of that process is to prove to any doubters that they’d better

start supporting bigger blocks or they’ll be left behind, and to give them

a chance to upgrade before that happens.


Because if we can’t come to consensus here, the ultimate authority for

determining consensus is what code the majority of merchants and exchanges

and miners are running.


Gavin Andresen


Some highlights of the conversation that ensued (with the originating e-mails redacted):


Are you really that pig headed that you are going to try and blow up the entire system just to get your way? A bunch of ignorant redditors do not make consensus, mercifully.


How is this being pigheaded? In my opinion, this is leadership.  If *something* isn’t implemented soon, the network is going to have some real problems, right at the time when adoption is starting to accelerate.  I’ve been seeing nothing but navel-gazing and circlejerks on this issue for weeks now.  Gavin or Mike or someone at some point needs to step up and say “follow me”.



Bitcoin XT is a patch set on top of Bitcoin Core, with a focus on upgrades to the peer to peer protocol. By running it you can opt in to providing the Bitcoin network with additional services beyond what Bitcoin Core nodes provide.

Bitcoin XT is more experimental than Bitcoin Core, and has a strong emphasis on supporting the needs of app developers and merchants. By running it you not only provide additional services to the network but help build confidence in the implementations, contributing towards consensus for inclusion in a future version of Bitcoin Core.