---

name: bitcoin-l2-rootstock-rsk description: | Rootstock (RSK): EVM-compatible Bitcoin sidechain with merge mining and federation peg. RBTC native token, 30-second blocks, Solidity smart contracts. USE WHEN: building Bitcoin DeFi via EVM contracts, integrating RSK peg, comparing with Stacks / Liquid. allowed-tools: Read, Grep, Glob

Rootstock (RSK)

RSK is a Bitcoin sidechain with EVM compatibility, secured by merge mining + a federation peg. Launched 2018 by IOV Labs / RSK Labs.

Architecture

• Federation: Powpeg n-of-m multisig holds bridged BTC.
• Merge mining: Bitcoin miners can simultaneously mine RSK blocks for additional reward (no extra hashpower needed).
• EVM: full Solidity smart contract support.
• 30-second blocks (vs Bitcoin's 10 min).
• Native token: RBTC = 1:1 BTC-pegged.

Peg architecture (Powpeg)

Federation members hold:

• Bitcoin multisig keys.
• HSM (Hardware Security Module) attestation hardware.
• Special PowPeg software signing peg-out only when proof-of-work threshold is met.

Peg-out (RBTC → BTC):

1. User sends RBTC to special bridge address on RSK.
2. Federation observes, schedules release.
3. After ~100 RSK blocks (~50 min), federation's HSMs sign release.
4. BTC sent to user's destination on Bitcoin.

RIF (RSK Infrastructure Framework)

Companion ecosystem:

• RIF Storage — IPFS-like.
• RIF Communications — secure messaging.
• RIF Naming — domain names on RSK.
• RIF Marketplace.

Powered by RIF token (separate from RBTC).

Major projects

• Sovryn — DEX, lending, derivatives on RSK.
• MoneyOnChain — stablecoin (DoC, BPRO).
• Beexo — wallet.
• RIF Wallet.

Comparison

Aspect	RSK	Stacks	Liquid
Smart contracts	EVM (Solidity)	Clarity	Limited
Block time	30s	~Bitcoin (10 min before Nakamoto)	2 min
Peg	Federation + merge mining	sBTC threshold	Federation
Maturity	2018, mature	2021, Nakamoto 2024	2018, mature

Use cases

• Bitcoin DeFi with familiar Ethereum tooling.
• Stable coins (DoC, USDS).
• Cross-chain bridges to Ethereum/BSC via Sovryn.

Implementations

• rskj — Java reference node.
• Web3 client compat — most Ethereum tools work (web3.js, ethers.js).
• MetaMask compatible with custom RPC.

Limitations

• Federation trust for peg.
• Merge mining depends on Bitcoin miners' participation.
• Solidity vulnerabilities inherited from EVM.

See also

• stacks/SKILL.md
• botanix/SKILL.md
• bsquared/SKILL.md
• bitlayer/SKILL.md