Chainmerger — unifying blockchains after a fork


This chainmerger proposal requires a hardfork from the perspective of both the Bitcoin Core and Bitcoin Cash protocol. The new Bitcoin node would need to bundle the legacy consensus code of both protocols and validate different block height intervals differently. This in itself is not unusual, as Bitcoin ABC nodes already perform this type of block height sensitive validation today (they validate blocks #1–478558 according to Bitcoin Core consensus rules and blocks >#478558 according to Bitcoin Cash consensus rules). The difference in this example being that the chainmerger node syncs both blockchain histories post-#478558 in parallel and validates both chains.

A chainmerger between Bitcoin and Bitcoin Cash, forking at block height 478558 and merging back together at some future block height X+1.
  • The 21M total cap must remain untouched
Chart from


The long-strawers of the bunch in this chainmerger are the users who bought BCH at lower prices than 0.1379 and the users who sold their BCH over that same price. The users of the opposite category, meaning the users who bought BCH at higher prices than 0.1379 and users who sold their BCH at lower prices 0.1379 makes up the short-strawers of the bunch. Arguably the biggest losers of this deal are the users who bought BTC after August 1st, who would have their BTC balance deducted by -13.79% with no other compensation. This would probably be unacceptable to most BTC holders, although one could argue that the users who bought only BTC and not BCH got their coins at a discounted price at the time, since a part of the community and hashpower was allocated to a different chain at the time of their purchase. There are also many other issues with this approach that one can think of, one instance being he game theoretical incentives it creates for miners to buy BCH and switch to mine BCH to increase the BCH merger coefficient that would need to be addressed.



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