rhino.fi is a self-custodial DeFi platform. This means that the funds you see and hold on the platform remain completely under your control, always.
Your funds cannot be moved or sold without your permission, and you can always recover your funds even if, for some reason, our website were to stop operating, from the Data Availability Committee.
This provides a level of security and transparency that wouldn’t be possible on a centralised cryptocurrency exchange.
When users first onboard to rhino.fi, they choose their wallet and connect their existing one. As in any DeFi application, this wallet enables users to control their funds and give permission to trade, invest, or bridge. Users are then asked to complete several steps, and make a deposit.
The deposit step is different from a deposit into a centralised exchange, as it moves users’ funds into the rhino.fi ‘smart wallets’. These smart wallets are what enable rhino.fi to provide an improved, consistent user experience across the entire platform and all the chains and L2s that we support.
The rhino.fi smart wallets are the core logic that powers the platform. These hold users’ funds, and allow us to provide the same quality of UX no matter which chain or L2 users are active on.
These smart wallets can be thought of as ‘upgrading’ users’ existing MetaMask wallet (or whichever wallet they normally use). Users still control their funds, using signatures from the wallet they normally use, but they now have several additional capabilities including:
- No more token approvals.
- Lower fees on transfers and trades.
- Instant bridge access.
- Easy one-click access to yield opportunities
- Pay fees in any currency instead of the native fee of the chain.
rhino.fi’s smart wallets on Ethereum Virtual Machine “EVM” chains are relatively simple, and can be viewed here.
They contain the following primary functionality:
- Track user balances
- Swap funds via DEX aggregators
- Send funds to other addresses
- Invest funds into yield opportunities
- Conduct emergency withdrawals out of the smart wallet.
In addition to the EVM smart wallets, rhino.fi also maintains a smart wallet built on StarkEx. rhino.fi runs a standalone StarkEx instance, which is actually a fully fledged, customised Ethereum L2 rollup. This gives a huge amount of flexibility over what can be accomplished, and the user experience that can be enabled. However at its core, just like the EVM smart wallet, the rollup enables the following functionality:
- Track user balances
- Trade funds on Ethereum with significantly lower gas costs than Ethereum L1.
- Send funds to other addresses.
- Invest funds into yield opportunities.
- Perform emergency withdrawals out of the rollup.
One point of difference with the StarkEx wallet is that it operates using a different public-private key pairing than Ethereum and the EVM. This means that a second key, which we call the ‘Trading Key’, must be generated and stored securely. Transactions on StarkEx are signed using this key instead of your regular (for example MetaMask) wallet keys. The trading key is encrypted and backed up, and can be recovered if lost by signing with your Ethereum wallet key.
Meta Transactions and Gas Abstraction
One of the upgrades enabled by the rhino.fi smart wallets is to abstract away transaction broadcasting from users.
When using the platform, users only need to sign transactions off-chain, which carries no cost, and send that signature to rhino.fi. We then take care of broadcasting the transaction quickly and safely, and pay the blockchain fee on the user’s behalf. This has the following advantages:
- Quick, hassle-free broadcasting (no need to replace or increase gas price).
- No need to hold funds in native tokens such as ETH, BNB or MATIC to pay gas.
- User pays no fees if the transaction fails (for example due to prices changing).