BLAKE2b and eCash Aren't the Same Fork: A Node Operator's Action Checklist

Action item, up front: none, unless you deliberately choose to interact with one of the two new chains running alongside Bitcoin since August 2026. Your real BTC sits on the chain with over 99% of hashpower, unchanged. The actual risk isn't losing access to your coins because a fork exists, it's a wallet connecting to the wrong chain with no error message at all.

BLAKE2b and eCash keep getting lumped into one governance argument. They aren't one story. Different origin, different mining algorithm, different motive, zero coordination between the two teams. This piece skips the debate recap you've already read and goes straight to what changes operationally, and what doesn't.

The two chains, side by side

(Figures as of September 5, 2026. Both chains' state changes with every block; verify against a live source before acting on any of it.)

Why BLAKE2b exists at all

eCash has nothing to do with any of that

eCash is a separate project end to end. Paul Sztorc, the LayerTwo Labs founder behind BIP-300 and BIP-301, is finally shipping drivechains outside of core consensus, since Bitcoin never adopted them after years of proposing. The chain keeps SHA-256, forking through a one-time difficulty reset to minimum rather than an algorithm swap, and activates drivechains from genesis.

Rollout runs by block height, not calendar date: alpha at block 963,648 (August 23), beta at block 967,680 (September 20), and the permanent mainnet split at block 973,728 (October 31, the whitepaper's 18th anniversary). Alpha and beta distribute pECX, non-final practice tokens at a 1:1 ratio to BTC held at the relevant snapshot, later burned and exchanged for permanent ECX. Alpha traction was real: over 25,092 blocks mined in roughly 13 hours, 3.53 PH/s of hashrate, and any idle SHA-256 rig, an old Antminer S9 included, can mine it without new hardware.

The controversial part is distribution, not the tech: a share of the roughly 1.1 million BTC typically attributed to Satoshi Nakamoto reportedly wouldn't be mirrored 1:1 and would instead go to early backers and development [VERIFY: the exact split figure varies by source; confirm against eCash's own documentation before citing a precise number]. Sztorc's own line on it: "we do not take any of Satoshi's BTC, BTC balances are untouched by eCash." Whichever side you find more convincing, it's a dispute about how a new coin gets allocated, not about whether your existing Bitcoin is at risk.

What happens to your node: nothing

Run standard Bitcoin Core or any conforming implementation without touching config, and neither fork changes anything about it. Your node keeps validating the same chain with the same SHA-256d proof of work it already validated. Neither chain can reach back and affect a standard installation: BLAKE2b split off because of a rule change your node already rejects by design, the same mechanism that rejected BIP-110 signaling in the first place, and eCash is a sibling chain with its own effective genesis, not a modification of the chain you already follow. The only way your node gets pulled into either is if you actively point it at their network.

The real risk: mixing up which chain you're on

This is the section that justifies the whole piece. BLAKE2b and eCash both share Bitcoin's genesis block, network magic, and address format with real Bitcoin. That means a wallet pointed at the wrong server doesn't error out, it syncs cleanly, shows a balance, shows transaction history, and gives you no signal that you're not on the chain you meant to be on.

The concrete case is Sparrow's dedicated BLAKE2b build (version 2.5.4, shipped August 31 by developer paulscode). Its release notes spell out the exact failure mode: because the two mainnets share genesis, network magic, and address format, a wallet connected to the wrong server syncs without error and shows a balance from a chain the user never chose. That build's fix reads the fork point the server itself reports via server.features and rejects any server that disagrees or doesn't report one at all. If you're touching either chain, the question that matters before connecting a wallet isn't which client version you're running, it's how you're confirming that specific server is actually on the chain you think it is. Skip that verification and the risk stops being theoretical.

Isolating a node, if you're indexing either chain

Both chains keep Bitcoin's network magic and standard ports (8333/8332), so pointing a node at either without isolation risks cross-traffic with mainnet. Three non-optional steps:

• Dedicated datadir. Never share a data directory between your Bitcoin node and a node for either fork. Structurally similar databases, not interchangeable ones.
• Pinned peers. Don't let peer discovery pick for you. On a minority network reusing mainnet's magic bytes, connecting to the wrong peer can put you on a different chain than you intended.
• Verify the fork block hash. Before trusting any sync, confirm the split block's hash (961,632 for BLAKE2b, 963,648 for eCash) matches independent sources, not just what your freshly-synced node reports back to itself.

Skip this entirely if you're not running a node for either chain yourself.

Handling balances: the operation order is what matters

Both chains inherited Bitcoin's full history up to their split point, so any BTC you held then mirrors as a balance there too (formally, on eCash, after the pECX-to-ECX conversion on October 31). None of this is time-sensitive. If you decide to access that mirrored balance, sequencing is the only thing that can actually go wrong.

Move your real Bitcoin to a completely fresh seed first. Only after that, with the old keys already emptied of real BTC, use them to touch the fork chain. Never the reverse. BLAKE2b's replay protection runs through SIGHASH_UNIFIED, an opt-in signature extension (a wallet implementing it, like the Sparrow build above, explicitly marks a send as protected), not a universal guarantee: a signature without that flag stays valid on both chains at once, and anyone who sees it broadcast can replay it where you didn't intend. eCash's protection is similarly opt-in through official software and an explicit separation step, not automatic from the mere existence of a mirrored balance. Touch the fork chain first and something goes wrong, you risk real BTC. Touch it second from an already-emptied seed, worst case you lose a balance you'd never spent through normal channels anyway.

Hygiene, and the absence of a deadline

No legitimate tool for checking, claiming, or converting a balance on either chain needs your seed phrase. Not one. There's no real claim window with a hard deadline for the mirrored balance you already have from having held Bitcoin before either split; a sense of urgency, "before it expires," "only a few hours left," is itself the more reliable signal of a scam than any legitimate feature of either project described here.

None of this is a price call on either chain, or a recommendation to buy, sell, or participate in either. Our own node's live state, following the main chain with over 99% of network hashpower and zero action on our part, is public at Network and mining, and the full BIP-110 failure writeup is in our earlier coverage.

Last updated: September 5, 2026