Protocol Architecture

Protocol Architecture

This page gives a birds-eye view of how assets move through the Rover protocol — from Layer-1 Bitcoin all the way to rovBTC and back.

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1. Actors & Contracts

Layer	Component	Purpose
Bitcoin L1	BTC	Native Bitcoin held by end-users
Botanix	Bridge	Locks / unlocks BTC on L1 and mints / burns wrapped BTC on Botanix
Botanix	pBTC (ERC-20)	1 : 1 wrapped BTC used inside EVM
Botanix	stBTC (ERC-20)	pBTC deposited into the staking pool earning protocol rewards
Botanix	RovBTC (ERC-4626)	Vault holding stBTC and issuing rovBTC shares

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2. High-level flow

Bridging back to L1 is optional — users can also keep the unlocked BTC on Botanix.

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3. Step-by-step

3.1 Bridging BTC ➜ Botanix

1. User locks BTC in the Bridge on Layer-1.

2. The bridge mints the equivalent amount of Botanix native BTC (gas token).

3.2 Deposit routes into RovBTC

Route	Function	What happens internally
Native BTC	depositBTC	Vault wraps BTC → pBTC → stakes to stBTC, then mints rovBTC
pBTC	depositPBTC	Vault stakes pBTC to stBTC, then mints rovBTC
stBTC	depositStakedBTC	Vault pulls stBTC directly and mints rovBTC

All three flows converge on the same outcome: the vault ends up holding stBTC and the user receives rovBTC shares.

3.3 Yield accrual

The stBTC balance inside the vault grows over time as staking rewards are harvested (stBTC.harvest()). Consequently each rovBTC share becomes worth more pBTC/BTC.

3.4 Withdrawals

1. User calls withdraw, redeem, or redeemNativeBTC.

2. Vault redeems the required stBTC back to pBTC.

3. A fee on gains (if any) is transferred to rewardsFeeReceiver.

4. Net pBTC is transferred, or unwrapped to native BTC, and optionally bridged back to L1.

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4. Where to integrate

Stage	API / Contract	Typical integrators
Bridge	Bridge UI / SDK	Centralised exchanges, wallets
Wrap / Unwrap	pBTC.deposit / pBTC.withdraw	Wallets, bridges, aggregators
Stake / Unstake pBTC	stBTC.deposit / stBTC.redeem	Yield optimisers
Vault	RovBTC (this repo)	Lending markets, portfolio trackers, treasuries

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6. Further reading

• Staking — Deep-dive into fees and calculations.

• Third-Party Integrations — Code examples for front-end and on-chain use-cases.