Bitparking.

Bitparking was a mining poolMining poolA group of miners who share the work of finding blocks and split the rewards, so each gets paid steadily instead of rarely. opened by Chris Double, a programmer known on the Bitcoin forum as doublec, who in 2010 had run one of the first public Bitcoin pools. It mined bitcoin together with Namecoin, Ixcoin, Devcoin and other coins built from Bitcoin’s code, counting the same work for all of them, which is called merged mining. Double opened a forum thread for it in January 2012. mempool.space credits it with 583 blocks, from 17 March 2013, the first to carry its name, to 18 March 2014.

Bitparking first paid miners a set amount for each piece of work they sent, known as pay per share. By 2014 it shared out each block’s reward by the double geometric method, or DGM, which pays according to recent work, and gave the transaction fees in a block to the miner whose machine found it. Each block’s first transaction paid most of the reward to one of the pool’s addresses, and the pool paid its miners from there. These are payments to the pool’s miners, separate from the transactions confirmed inside the block.

Bitparking didn’t close. On 6 April 2014 a new forum thread announced the pool as mmpool, at mmpool.org, saying it “used to be known as Bitparking”, and from then on its blocks carry the name mmpool instead. mempool.space lists those blocks separately, under mmpool: 44 more, from 8 April 2014 to 14 December 2022.