What is Phasis
A Deribit-style on-chain options exchange on Sui.
Phasis is a cash-settled options exchange built entirely on-chain on the Sui network. It gives traders the same market microstructure they expect from professional venues — a real central limit order book, portfolio-level margin, and European-style options on SUI, BTC, and ETH — without custodians or off-chain matching.
The protocol is live on Sui testnet. Mainnet deployment is pending an external security audit.
A real orderbook, on-chain
Most DeFi options protocols route orders through an automated market maker (AMM). Phasis uses DeepBook v3, Sui's native central limit order book (CLOB), as the matching engine for every option series. Each strike-and-expiry pair has its own dedicated DeepBook pool embedded directly in the on-chain Series object.
This means:
- Limit orders, market orders, post-only, fill-or-kill, and immediate-or-cancel order types all work as expected.
- Makers and takers interact with a transparent, auditable order book — not a pricing curve.
- Liquidity is not fragmented across AMM pools; it concentrates in a single venue per instrument.
Portfolio margin, not gross collateral
Phasis uses a portfolio-margin stress model (an N-point Black–Scholes stress grid) rather than gross notional or per-position collateral.
When a trader places an order, the protocol computes the worst-case mark-to-model loss across a grid of spot and volatility scenarios for the entire portfolio. Only that net risk figure needs to be covered by free balance. In practice this means:
- Defined-risk structures (spreads, covered positions) require a fraction of the collateral a naked short demands.
- Margin is recomputed atomically at every order, fill, and liquidation — no stale exposure.
- A dedicated off-chain stress-publisher keeper refreshes the on-chain
StressSnapshotwith fresh Black–Scholes grids before each margin check.
Native to Sui
Every core object — OptionsRegistry, Market, Series, Account<USDC>, StressSnapshot — is a shared Sui object. Downstream protocols, liquidation bots, and oracle keepers interact with them through direct on-chain reads and programmable transaction blocks, with no bridges or proxies.
The TypeScript SDK (@phasis-lab/sdk) exposes typed bindings for every entry function, making it straightforward to build integrations, trading bots, or analytical dashboards.
How it fits together
| Layer | Component |
|---|---|
| On-chain | Move package + vendored DeepBook v3 |
| Keepers | Rust services: stress-publisher, cranker, liquidator, market-maker |
| SDK | @phasis-lab/sdk TypeScript bindings |
| Frontend | Next.js + @mysten/dapp-kit wallet integration |
Settlement is European cash-settled in USDC. At expiry the cranker reads the Pyth EMA price for the underlying asset and distributes intrinsic value to in-the-money holders.
Where to next
- Connect a wallet — set up your Sui wallet and link it to Phasis.
- Trading Guide — order types, the option chain, reading positions, and closing trades.
- Protocol — margin model, settlement mechanics, liquidations, and on-chain architecture.
- Developers — SDK reference, keeper architecture, and integration examples.
- About — team, roadmap, and audit status.