Overview

A Coffer lets you raise liquidity against your staked ETH without exiting the validator and without reducing stake. You deploy your own Coffer contract, set it as your validator’s withdrawal credentials, and sell bonds on terms you choose. The principal of every bond, net of the protocol fee, lands in your own wallet the moment the bond is bought.

The whitepaper puts the economics in one sentence. “A validator that earns more yield than it pays out on sold bonds increases its overall earnings.”

What it asks of you

Bonds are paid from the ETH sitting in your Coffer contract, and your one duty is to keep that balance sufficient. At every moment the contract must hold at least the sum of maturity values across all matured, unpaid bonds. Your consensus rewards flow to the contract on their own, and you can top the balance up at any time. How you source the balance is up to you, the contract only checks that a matured bond can be paid.

The shortest duration you sell is the least notice you will ever have, a bond can mature no sooner than your minimum duration after its purchase. A fresh bond adds a liability with no backing in the contract, since the principal went to your wallet, so size your minimum duration against how often you actually check on your validator.

What a default means for you

The moment any single matured bond cannot be paid in full from the contract balance, anyone can declare your default. Bond sales and every withdrawal path freeze, every outstanding bond becomes claimable at its full value, and anyone can request your validator’s full exit. The contracts README puts it plainly, in practice a default should be treated as the end of the validator and of the Coffer. The Default page walks through the mechanics, the risks page covers what can eat the stake behind your bonds, and the only way out of a default is to pay every bond in full.

Where to go next

Before you create a Coffer lists what to have ready. Create a Coffer walks the four steps in the app. Point your validator at the Coffer covers the deposit and the credentials, and Coffer lifecycle and statuses explains every state your Coffer can be in. Ownership covers handing the Coffer to another wallet.