Jeff Garzik is a software developer publicly known as jgarzik. Specific code and BIP authorship establish contributions, not personal control of Bitcoin consensus.
GitHub associates Jeff Garzik with jgarzik. For historical code, inspect the specific repository and version; a present profile alone does not establish past or current authority over every Bitcoin release. [Garzik — public developer profile]
Garzik’s cpuminer README describes a multithreaded Bitcoin CPU miner. pooler/cpuminer explicitly identifies itself as a derivative for Litecoin and Bitcoin; later fork features cannot automatically be attributed to the original version. [Garzik — reference cpuminer README][Pooler — cpuminer ancestry]
Picocoin contains the C library libccoin and marks its HD wallet and brd node WIP. The repository has been archived since 15 February 2024. Available source is not evidence of a finished, currently maintained safe product. [Garzik — Picocoin archive and README]
Garzik’s BIP 35 describes a mempool request and an inv response containing that node’s transaction hashes; getdata can request the data. This is a local pool of unconfirmed transactions, not a complete global list or proof of block inclusion. [BIP 35 — mempool message][Bitcoin Core 29.0 — local mempool RPC]
BIP 100 names Garzik, Tom Harding and Dagur Valberg Johannsson. Its proposed recalculation every 2016 blocks uses a 75% mining majority and bounded limit changes. Its status is Closed; describing the algorithm does not prove network-wide adoption. [BIP 100 — dynamic block-size proposal]
BIP 100 explicitly says the first block above the original 1 MB limit separates nodes still enforcing that fixed limit. Miner votes alone therefore do not change an unupgraded node’s validation rules. [BIP 100 — dynamic block-size proposal]
Garzik’s BIP 102 proposed a one-time 2 MB limit with a time condition and support from 95% of the last 1000 blocks. It is also Closed and warns of incompatibility with older validating clients; it is not today’s block-size definition. [BIP 102 — two-megabyte proposal]
The registry marks BIP 35 Deployed in Peer Services, but BIP 100 and BIP 102 Closed in Consensus (hard fork). Deploying a network message does not establish deployment of another proposal by the same author. [BIP 35 — mempool message][BIP 100 — dynamic block-size proposal][BIP 102 — two-megabyte proposal]
For the clearest picture, read this entry together with Cynthia Lummis, Mike Hearn, Blocksize War. The reverse links also lead from Mike Hearn.