I'd be interested to know about these supposed btcd mainnet forks that
have occurred due to a consensus failure since it came out of alpha.
I'll go ahead and save you some research time - there hasn't been one.
I'm not claiming there will never be one as that would be just as
foolish as claiming Bitcoin Core won't have any more either.

As you alluded to, there was a _potential_ instance found due to fuzzing
which prompted a thorough audit of the code base.  It was fixed before
any problems occurred and resulted in improved test coverage in Bitcoin
Core as well.

On the other hand, Bitcoin Core has had actual forks on mainnet during
the same period.  I'm not casting stones at Bitcoin Core here, because
as I've said many times, none of us are perfect.  No matter how careful
everyone is, it is bound to happen from time to time.

Until this community decides to get serious about facing the reality
that an infrastructure built on a single implementation with no real
disaster prevention measures for unintentional incompatibilities between
different versions of that implementation is incredibly fragile, there
will continue to be more unintentional hard forks regardless of the
existence of alternative implementations.

It has not ended poorly by any means.  It has already led to several
improvements such as improved test coverage and more robust and modular
code.


On 9/1/2015 6:11 AM, Monarch via bitcoin-dev wrote:
> That would be incredibly foolish given the history, where even heroic
> attempts at making consensus compatible re-implementations have ended
> rather poorly.  bitcoin-ruby and btcd have collectively had numerous
> consensus failures, some only recently found by fuzzing the scripting
> environment.  There are more failures than publicly disclosed, and
> almost any failure can be leveraged to split the network and steal
> money.   Ethereum attempted to create four clients, written to a
> defined specification, and even with all the money in the world has
> managed to have numerous consensus failures due to misunderstanding or
> implementation.