Zest Protocol has launched a capped mainnet demo of its Bitcoin Collateral Vaults on September 23, marking the first full public-mainnet deployment of its native-Bitcoin collateral vault infrastructure. According to Zest Protocol, Bitcoin Collateral Vaults are self-custodial vaults on Bitcoin L1, where Bitcoin's own rules govern spending and the design supports BitVM proof verification. Each vault holds one user's BTC with coins from different users never pooled, and each vault is a Taproot output with spending paths fixed at deposit, limiting where BTC can move. The mainnet demo runs with real BTC and real USDC, capped per wallet, allowing users to test the full flow at small scale by depositing BTC into individual Bitcoin Collateral Vaults and borrowing USDC on Ethereum. Proof of the mainnet demo's functionality, including Bitcoin transaction hashes, vault addresses, and EVM contract interactions, is available for independent verification on public block explorers.
In the first production phase, independent guardians handle settlement checks when events such as repayments or liquidations occur on the lending chain. When an attestation triggers settlement, guardians check that the borrower authorized the settlement in advance, and a quorum of guardians can reverse invalid payouts during a contest window. Zest plans to shift this role to BitVM, a system for verifying computation on Bitcoin without changing its rules. Under Zest's planned design, parties claiming repayments or liquidations post claims on Bitcoin, with challengers having a set window to dispute claims using zero-knowledge proofs. The documentation notes that security depends on the construction Zest selects and honest challengers acting in time, with BitVM3 benchmarks showing onchain costs under $100.
According to Spark's research, Bitcoin is the largest crypto asset by market value, yet almost all of it sits still. The research counted 91,332 BTC across Bitcoin layer-2 networks in May 2026, or about 0.46% of the circulating supply. Adding every wrapped token and all Babylon staking lifts the share to only about 0.8%. Most holders who do put BTC to work wrap it first, with a custodian keeping the real coins and a token such as WBTC standing in for them on Ethereum. WBTC holders were reminded of this dependency in August 2024, when BitGo said it would shift custody to a joint venture with Justin Sun-linked BiT Global, with Aave's Ethereum market holding about $2.2 billion in supplied WBTC at the time. Coinbase went further and delisted WBTC in December 2024, citing the risk that control would "fall into the hands of Justin Sun."
According to Tycho Onnasch, Founder of Zest Protocol, "We've spent five years on programmable Bitcoin, first on Stacks and now on Bitcoin itself. Today you can put real BTC in a vault on Bitcoin and borrow against it on mainnet. That's why Zest Protocol exists: turning Bitcoin from an idle asset into productive capital." Tim Draper, Founder of Draper Associates, stated "I backed Zest Protocol because this team has been building on Bitcoin longer than almost anyone, and they know how to ship great products with amazing user experience. Seeing real Bitcoin collateral working on mainnet, with the coins never leaving Bitcoin, is something I'm incredibly excited about." The mainnet demo builds on lessons from two years of running the Zest Protocol Stacks Market, the largest lending market on Bitcoin L2s, which reached over $100 million in peak TVL with zero bad debt and no BTC lost. Bitcoin Collateral Vault borrowers get partial liquidations instead of all-or-nothing, partial withdrawals, and a vault that will be controlled by one ordinary Bitcoin key, with nothing else to manage.
Zest Protocol was founded by core contributors to the Stacks blockchain, including co-architects of the sBTC and Nakamoto upgrades. Prominent investors included Draper Associates (led by Tim Draper), YZi Labs, Trust Machines, Flow Traders, and Asymmetric. The protocol's native token, ZEST, was launched in May 2026 via Binance Alpha and is currently traded on major exchanges including KuCoin, Gate, MEXC, and HTX. The native self-custodial approach adopted by Zest Protocol tries to remove third-party counterparty risk, though other problems like smart contract vulnerabilities might still persist. The bitcoin-backed credit market is currently sized at roughly $16 billion, according to the Bitcoin Digital Credit Report compiled by Apyx and BitcoinTreasuries.net, with estimates suggesting it will grow to $130 billion by 2030 as preferred equity structures scale.
