The Sui Foundation announced that Hashi, its Bitcoin finance infrastructure, will begin a phased mainnet rollout later in October. The network is supported by more than $500 million in capital commitments from a coalition of more than 20 launch partners. The figure represents pledged capital rather than funds already deposited on-chain.

Hashi was developed by Mysten Labs, the founding contributor to the Sui blockchain. It allows applications on Sui to use Bitcoin as collateral without requiring users to transfer native BTC into DeFi smart contracts. Users deposit Bitcoin, which remains secured on the Bitcoin network, and receive a corresponding hBTC token minted on Sui. This hBTC can then serve as programmable collateral in financial products. When positions close, hBTC is burned and the underlying Bitcoin is released back to a Bitcoin address.

Applications and Product Scope

The infrastructure targets lending, borrowing, credit arrangements, vaults and structured products. Third-party developers will independently create and offer these financial products using the Hashi framework. Vault operators expected to participate include Aftermath, Concrete and Fluid. The system is designed so that independent parties build on the shared collateral layer rather than relying on a single application.

Sui stated that the initial capital commitments will support Bitcoin-backed markets as partners finish integrations and begin deploying BTC or stablecoins. Access will expand in stages as custodians, wallets and application providers complete their work. No single public launch date has been set beyond the October timetable.

Launch Partners and Institutional Access

The launch coalition spans custody, trading, liquidity, wallets and decentralized finance. Named participants include BitGo, Bullish, Cumberland, FalconX and Ledger. Anchorage Digital has joined as a day-one launch partner.

Anchorage Digital plans to provide institutional clients with two access routes. One uses its Atlas settlement and tri-party collateral platform, allowing Bitcoin to remain within qualified-custody arrangements. The second uses Porto, its institutional self-custody wallet, intended for hedge funds, crypto venture funds, miners, liquidity providers and market makers seeking more direct control. The company also intends to supply stablecoin liquidity to Hashi.

Technical Design and Security Controls

Hashi employs multi-party computation alongside Sui smart contracts to manage Bitcoin movements. Deposited BTC is held through a 2-of-2 structure that requires authorization from the Hashi validator system and a separate guardian before collateral can leave. The Guardian Layer functions as an independent check that can slow or stop suspicious transfers.

Mysten Labs documentation describes Hashi validators jointly operating a threshold Schnorr signer via multi-party computation. A second signer running in a cloud enclave independently enforces policies. Smart contracts have undergone formal verification by Certora, and the cryptographic protocol received a review from CommonPrefix. The testnet launched on July 22, 2026, after earlier development work that began with a March introduction and a global testnet phase in July.

Hashi’s Move packages operate as standard Sui packages outside the system framework. Each participating committee member runs separate node software, while protocol-critical state remains on Sui.

Development Path and Market Context

Earlier announcements identified additional participants such as Erebor Bank, Fordefi, Blockdaemon, CF Benchmarks and Inveniam Capital, along with several Sui lending protocols. Cumberland, Fluid and SwissBorg joined the coalition in June ahead of the testnet opening. By early September more than 20 institutional partners had signed on, covering custody, liquidity, lending, asset management, insurance and security.

A legal analysis from attorneys at Fenwick in April concluded that locking BTC through Hashi and receiving hBTC should not constitute a taxable event under the U.S. federal income tax principles examined, on the basis that hBTC represents ownership of the underlying Bitcoin rather than a sale or exchange. The analysis is a legal opinion and not an Internal Revenue Service ruling; tax treatment depends on specific facts and circumstances.

The phased mainnet is expected to begin supporting native BTC deposits, hBTC minting and the use of Bitcoin collateral inside live Sui applications before the end of October. Measurable activity will depend on how much of the committed capital enters the system, how much native Bitcoin is deposited, how much hBTC is minted, and which third-party lending or vault products become available to users.