What is Stacks (STX)?
Stacks is a blockchain layer built to expand Bitcoin’s programmability without altering the core protocol. It lets smart contracts treat BTC as a native asset and settle transactions directly on the Bitcoin ledger. The network’s own token, STX, both pays for computation and ties the layer’s security to Bitcoin.
How does STX anchor Stacks to Bitcoin?
Stacks uses a consensus system called Proof of Transfer (PoX). Instead of burning electricity, miners send Bitcoin to the network to compete for the right to produce a new block and earn STX. That Bitcoin isn’t wasted—it’s recycled as a reward for Stackers who lock STX and help secure the chain. This cycle permanently binds Stacks’ history to the Bitcoin blockchain. To undo a Stacks transaction, an attacker would have to reorganize Bitcoin’s own ledger, meaning the layer is shielded by the full weight of Bitcoin’s hash power.
What roles does the STX token play?
Within the ecosystem, STX carries four key responsibilities. First, it acts as gas to run smart contracts. Second, it serves as the block subsidy that attracts miners to the PoX process. Third, it rewards the signers who operate the sBTC two-way peg. Fourth, it’s the asset users lock through Stacking to earn a yield in BTC. Stacking operates in recurring cycles: participants lock their STX for a set period and receive BTC from the miners’ commitments; those without enough to lock independently can delegate to a stacking pool. STX is also needed to pay registration fees when creating new on-chain tokens or NFTs.
Smart contracts on Stacks are written in Clarity, a language designed to let developers verify a contract’s complete behavior before execution and to read Bitcoin’s live state natively. The sBTC peg adds a bridge: BTC can move onto the layer as a 1:1 backed asset and be withdrawn back to the main chain. Together, these pieces turn Bitcoin into the settlement layer for a wider DeFi ecosystem.
