sats-staker

About the Project

SatsStaker is a non-custodial, smart contract-based protocol I built on the Stacks Layer 2 blockchain to enable secure Bitcoin yield generation. Users can stake sBTC, a wrapped, 1:1 Bitcoin-pegged token, and earn time-weighted rewards directly on-chain — all without giving up control of their assets.

Inspiration

The idea was born from a desire to unlock Bitcoin yield opportunities in a trust-minimized and transparent way. Most BTC yield products rely on centralized custody, so I set out to build a secure alternative where users remain in full control through Clarity smart contracts.

What I Learned

Through building SatsStaker, I gained valuable experience with:

• Writing smart contracts in Clarity
• Implementing non-custodial staking mechanisms
• Calculating rewards using time × amount-based logic
• Designing admin time-locks and safety checks for protocol updates
• Managing on-chain state and ensuring gas efficiency

How I Built It

• Language: Clarity
• Stack: Stacks blockchain, sBTC (SIP-010 token standard), Clarinet, Stacks.js
• Contract Address (Testnet): ST2VXPMB7WBJRS0HPJENJD7FR35907JV4X1E64DGN.sats-staker
• Core Functions: stake(), unstake(), claim-rewards(), calculate-rewards()
• I used Clarinet to write and test smart contracts, and designed the reward system to calculate yield per block using a basis point-based APY model.

Challenges Faced

Some key challenges included:

• Ensuring accurate, fair reward accrual across varying stake durations
• Designing robust error handling and time-based unstaking logic
• Preventing potential attacks with reentrancy guards and underflow checks
• Creating a secure yet flexible admin configuration system with time-lock controls

Security Features

• Non-custodial design — funds are never accessible by the contract unless triggered by the user
• Time-locks for all admin actions
• Input validation for reward rate safety
• Comprehensive state and access checks
• Full audit planned before mainnet deployment

Built With

• clarity