Stratum V2 Job Declaration: Choose Your Own Transactions

Job declaration is the part of the Stratum V2 spec that lets a miner construct its own block template, choosing which transactions to include, and declare that template to the pool. Instead of always mining whatever transactions the pool selected, the miner can decide for itself, while the pool still handles payout accounting.

Whoever picks the transactions in a block holds quiet power over what the network confirms and in what order. Under Stratum V1 that power sits with pools. Spreading it across many miners via job declaration makes Bitcoin harder to censor and more decentralized, which is a core reason Stratum V2 was designed.

The Job Declarator Client (JDC) runs on the miner side and builds the block template, typically using a local Bitcoin node as its transaction source. The Job Declarator Server (JDS) sits with the pool and validates and coordinates the declared jobs. Together they let a miner declare custom work while keeping the pool's accounting intact.

No. Job declaration is an optional advanced feature. You get all of Stratum V2's encryption, authentication, and efficiency benefits without it, simply by mining the pool's templates over an SV2 endpoint. Job declaration is the extra step for miners who also want to control transaction selection.

Philosophically, yes. Solo mining is already about sovereignty, and job declaration extends that to transaction selection: your hardware, your address, and your choice of what goes in a block you find. It is the fullest expression of independent mining, though it requires running your own node and the client software.