Rootstock (RSK)

Rootstock (RSK) is a long-running Bitcoin sidechain that adds a smart-contract platform compatible with the Ethereum Virtual Machine (EVM). It lets developers deploy Solidity contracts and run decentralized applications while settling value pegged to Bitcoin. BTC moved onto Rootstock becomes RBTC, a token backed 1:1 by bitcoin locked through the sidechain's two-way peg — so the asset that pays for computation on Rootstock is, economically, bitcoin.

Merged mining and security

Rootstock is secured by merged mining with Bitcoin: the same SHA-256 proof-of-work that secures a Bitcoin block can simultaneously satisfy Rootstock's consensus, so a participating pool earns sidechain fees for work it was already doing, at no extra energy cost. In practice the pool includes a commitment to a Rootstock block inside the Bitcoin work it distributes; a solution good enough for Bitcoin's difficulty wins both chains, while a solution that meets only Rootstock's much lower difficulty still produces a Rootstock block. A large fraction of Bitcoin's hashrate has historically participated, giving the sidechain proof-of-work security that a standalone chain of its size could never afford. Rootstock targets roughly 30-second block intervals, much faster than Bitcoin's ten minutes, which is what makes interactive applications tolerable.

The Powpeg

The two-way peg, called the Powpeg, is the mechanism that locks BTC on the Bitcoin mainchain and issues an equivalent amount of RBTC on the sidechain, with the reverse on peg-out. It is operated by a federation of functionaries running hardware-security-module-protected nodes whose signing behavior is constrained by proof-of-work: the HSMs only sign peg-out transactions attested by sufficient cumulative work, reducing reliance on the honesty of any single operator. It is important to be precise about the trust model — the peg is federated and defense-in-depth, not trustless the way holding your own UTXO is. Bitcoin cannot natively verify events on another chain, so every sidechain peg involves some custodial construction; Powpeg is one of the more hardened designs, but users of RBTC are accepting it, and should know they are.

Why it matters to miners

For mining operators, Rootstock is the concrete, running example of how the same joules can earn fees on more than one chain. Merged-mining revenue is modest compared with Bitcoin rewards, but it is close to free at the margin for a pool that supports it, and it demonstrates a broader principle D-Central cares about: SHA-256 work is a general security commodity, and miners are its producers. For everyone else, Rootstock shows one path to programmability that does not touch Bitcoin consensus at all — the base layer stays conservative while experimentation happens beside it.

Participation is pool-level plumbing rather than a per-machine decision. An individual miner does not configure anything on an ASIC to merge-mine Rootstock; the pool's infrastructure assembles the dual commitment and distributes ordinary SHA-256 work, so the choice is made when you choose a pool. On the usage side, the developer experience is deliberately familiar: EVM-compatible wallets and tooling work with Rootstock endpoints, contracts are written in Solidity, and transaction fees are paid in RBTC — meaning the network's fee economy runs on pegged bitcoin end to end. That familiarity is the strategic bet: meet developers where they already are, while anchoring settlement and security to the most conservative chain available.

Context among Bitcoin's layers

D-Central covers Rootstock neutrally alongside other base-layer extensions: federated designs like the statechain model, the proposed Drivechain soft fork that would let miners collectively custody peg funds, and off-chain systems like Lightning. Each occupies a different point on the trust-versus-capability curve. For current peg mechanics, functionary sets, and node details, consult Rootstock's own documentation — peg parameters are exactly the kind of fact that changes while glossaries stand still.