FAQ

Start

What is Euler?

Euler is modular onchain lending infrastructure. EVK vaults each hold one underlying asset and can lend it to eligible borrowers. Explicit collateral relationships connect vaults into markets, while the EVC coordinates accounts, sub-accounts, controllers, operators, and batched actions.

EulerEarn vaults provide a separate aggregation layer: users hold one Earn share position while configured roles allocate the deposited asset among enabled strategies.

Where should I start?

To understand the protocol, read Vaults and Markets.
To supply, borrow, use Earn, or manage a position, start with Use.
To integrate contracts or data, start with Build.
To launch or operate vaults and markets, start with Curate.

What is the difference between a vault and a market?

A vault is an ERC-4626 contract for one underlying asset, with its own configuration and roles. A market is the set of collateral and liability relationships between vaults. The liability vault controls which collateral vaults it accepts and applies the relevant oracle route, LTVs, caps, and account checks.

Related: Vault types and Markets.

Use Euler

What should I check before supplying or borrowing?

For supply, check the vault asset, available liquidity, caps, fees, governor or curator, interest-rate model, and any reward source. For borrowing, also check accepted collateral, oracle routes, borrow and liquidation LTVs, liquidation settings, and the position's health after the transaction.

How do I assess vault risk?

Review the vault together with its connected market: assets, collateral relationships, liquidity, caps, oracle routes, interest-rate model, LTVs, liquidation settings, hooks, governance, and addresses authorized to change configuration. These checks do not remove smart-contract, oracle, liquidity, collateral, governance, or total-loss risk.

How does EulerEarn work?

An Earn vault accepts one asset and issues ERC-4626 shares. Configured roles manage enabled strategies, caps, queues, allocation, and fees. Before depositing, review those roles, the strategy set, current allocation, withdrawal liquidity, loss accounting, and fees.

Who controls a vault or market?

Authority is deployment-specific. Review the onchain governor, curator, allocator, guardian, operator, timelock, and fee-recipient addresses, then inspect the exact permissions assigned to each. A role label alone does not establish authority.

Related: Managing positions, EulerEarn, and Risk curators.

Launch and operate

How do I create a vault or market?

Choose the asset and market topology, deploy or select the required vaults, configure collateral relationships, oracle routes, IRMs, caps, LTVs, liquidation settings, hooks, and governance, then publish labels and verify the deployed state. Use the Launch toolkit for the sequence and Curate for operating guidance.

How do I launch an Earn vault?

Define the deposit asset, strategy set, roles, caps, supply and withdrawal queues, allocation process, fees, liquidity plan, labels, and user-facing disclosures. Start with the Earn launch guide.

How do I choose an oracle route?

Identify the base asset, quote asset, and unit of account; then review the adapter, data source, update behavior, decimals, route precedence, manipulation resistance, and failure behavior. ERC-4626 share resolution is optional and should be used only when the vault conversion is the intended and reviewed pricing path.

Integrate

Which data source should I use?

Use the Data API for indexed and historical data, lens contracts for aggregated onchain reads, and direct contract calls or simulation for execution-sensitive state. Use vault metadata for display context; metadata and known-vault status are not safety verdicts.

How should I build transactions?

Use the Euler SDK for app-level planning, approvals, simulation, and execution. Use the EVC integration guide for lower-level batching, sub-accounts, controllers, collateral, operators, and permits. Verify chain, addresses, calldata, state changes, approvals, and post-transaction health before signing.

Where are contract addresses and ABIs?

Use Contract addresses and the Euler interfaces repository. Confirm the target chain, deployment version, bytecode, and interface before constructing a call.

Security

Where do I find audits or report a vulnerability?

Use the audit index to identify reports for the exact component and revision. Follow the current Cantina bounty page for scope, testing rules, eligibility, and submission instructions. Never test against production contracts or user funds unless the controlling rules expressly authorize the exact action.