Contracts and architecture
Isometric is a set of smart contracts on Base. Everything that touches funds or decides an outcome happens in them. The app, the keeper, and the indexer are conveniences that could be replaced without changing a single balance.
Where funds sit
| Contract | Holds |
| Long vault | Depositor cbBTC, reserved collateral for longs, long premium, and funded long payouts |
| Short vault | Depositor USDC, reserved collateral for shorts, short premium, and funded short payouts |
| Operations | The protocol's operating budget for settlement gas, keeper reimbursements, and treasury revenue |
Nothing else holds tokens. The pricing, risk, and oracle modules have no token permissions at all. The keeper and indexer hold nothing.
The two vaults never lend to each other. A long payout can only come from the long vault, a short payout only from the short vault, and neither can be used for operating costs.
What each contract does
| Contract | Responsibility |
| Market | The entry point for quotes, opens, and settlement. Enforces market mode |
| Calculator | Builds quotes, runs the strike search, marks open positions, checks risk limits |
| Ledger | Records positions, series totals, settlement prices, and claim state |
| Operations | Claims, automatic payouts, volatility samples, and keeper reimbursement |
| Long and short vaults | ERC-4626 shares, the four accounting buckets, share valuation, and custody |
| Pricing module | The volatility model and option valuation |
| Risk module | The configurable limits and their ceilings |
| Oracle adapter | Verifies RedStone prices against Chainlink, the sequencer feed, and answer bounds |
| Settlement engine | Validates round pairs, settles an hour, and runs the long conversion |
| Swap adapter | The fixed route used for the long conversion and long premium routing |
The split is deliberate: the contract that holds funds does not price, and the contract that verifies oracles cannot settle on its own. Each can be replaced through governance's delayed module path without touching the others.
The services around it
| Service | What it does | What it cannot do |
| App | Reads the chain, fetches signed prices, and builds transactions for your wallet to sign | Move funds, price a trade, settle |
| Keeper | Submits hourly volatility samples, settlements, and payout pages | Choose a price, pause, or move funds |
| Indexer | Builds the history behind Portfolio and the pool charts | Affect any balance or outcome |
Anyone can run a keeper. If Isometric's stopped, another could settle every position. If the indexer went stale, Portfolio history would lag but every position, claim, and balance would still be exactly what the chain says, because the app reads live state from the contracts for anything that matters.
Checking it yourself
Deployed addresses are listed in the deployment manifest the app loads, and every transaction the app sends can be inspected on a Base block explorer from the position page in Portfolio.