A look at Stratum V2, the first update to the open-source intermediary protocol used by many bitcoin miners since 2012, developed by Block's Spiral and others
Context & Ripple Effects
Block's mining push has been assembling piece by piece: Jack Dorsey teased the idea in late 2021, then Block committed to an open-source bitcoin mining system aimed at making mining more distributed and efficient. Around the same time, Blockstream raised $210M at a $3.2B valuation and acquired Israeli mining manufacturer Spondoolies, and Block has since moved into silicon with its own finished 3nm mining chip.
Stratum V2 fills in the software layer of that stack. The original Stratum has been the intermediary protocol between miners and pools since 2012, meaning whoever runs it sits between miners and the blocks they produce. An update developed by Block's Spiral and others targets exactly that chokepoint — the first revision in a decade to how mining communication works.
First-order effects
- Miners and pools still running the 2012-era Stratum face a migration decision: adopt the updated protocol or stay on software whose intermediary role the new version is designed to shrink.
- Block's Spiral gains a flagship open-source deliverable that anchors the distributed-mining system Block committed to building in January 2022.
Second-order effects
- Pool operators' discretion over transaction selection and block construction comes under pressure, since a protocol update at the intermediary layer redistributes power away from whoever currently runs it.
- Block's full-stack approach — open-source software plus its own 3nm chip — puts it in competition with incumbent ASIC makers and with Blockstream, which bought Spondoolies to sell mining hardware of its own.
Third-order effects
- If the pattern holds, bitcoin mining consolidates around vertically integrated open stacks — chips, systems, and protocols shipped together — while block-construction authority disperses from large pool intermediaries back toward individual miners, a structural shift in who controls the network's transaction flow.
The trend: Bitcoin mining infrastructure is moving from decade-old centralized pool intermediaries toward open-source, miner-controlled protocols bundled with vertically integrated hardware.