How your money is kept

Mirrorlane is a terminal for Lighter, the exchange where your account lives. Your deposits, positions and orders belong to that account, under your wallet’s address. We hold none of it.

Smart contracts on Ethereum hold the assets deposited on Lighter, along with the state root: the record of every account’s balances and positions, the order books and the rest of the exchange’s state. Your main account and its sub-accounts are all tied to your wallet’s address.

Mirrorlane’s servers never receive your funds, your trading key or the token that reads your account. Orders go from your browser straight to the exchange. For your money, our servers do one thing: they get deposit addresses on other networks for your wallet, and your browser checks that each address credits your wallet before showing it.

Lighter orders every transaction as it arrives and executes it at once. Batches of these transactions then go into zero-knowledge proofs, and Ethereum checks each proof before the contracts accept the new state. With every update, Lighter posts the data behind it to Ethereum, enough for anyone to rebuild every account’s state from Ethereum alone.

So a trade counts on the exchange as soon as it executes, and Ethereum confirms it later, once its batch is proven.

Apart from the exchange’s own rules, such as fees, funding and liquidation, money leaves your account only by a signature you control.

Signer	Can move funds	Where
Your trading key, made on this device	Secure withdrawals, and moves between your own accounts	Only to your own wallet, or your own accounts
Your wallet	Transfers to someone else, fast withdrawals, deposits	Wherever you sign for
Mirrorlane’s servers	Nothing	None

The terminal’s code in your browser signs with your trading key, so it can do only what that key can. The fee approval your wallet signs on Plus or Premium lets orders placed here carry the fee. It doesn’t let anyone withdraw or transfer your funds. More on each signature: Your trading key and What your wallet signs.

Lighter’s contract also has a governor, a multi-sig controlled by the protocol, which manages markets and the protocol’s settings.

If a withdrawal isn’t processed in time, you can still take your full balance out on Ethereum. Lighter keeps a queue of priority requests on Ethereum, such as withdrawals, that it must process within a set time. If it doesn’t, the contract freezes, and you can prove what your account holds from the data on Ethereum and withdraw the full value of your assets there, with no one else’s help. If Mirrorlane is unavailable has the steps.

Lighter publishes the security audits of its smart contracts and circuits on its Security audits page, beside its vulnerability disclosure policy.

Your Portfolio’s analytics are worked out in your browser and saved on your device; your history isn’t sent to our servers. We see only totals: the volume and the number of accounts trading through Mirrorlane. The exchange’s explorer is public, though, so anyone can read an account’s trades.

Keeping money on any exchange carries risk. Lighter’s Terms list them, from hacking and security weaknesses to uninsured losses, and a liquidation can take an account to zero. See Liquidation.