# Operating SingleDepositorVault

### What is the Single Depositor Vault?

The `SingleDepositorVault` is a vault structure that is designed to operate on funds owned by a single logical owner. It enables basic Aera functionality (guardianship, pausing, etc.) and also enables the vault owner to take actions on behalf of the vault such as depositing, withdrawing and arbitrary execution.

The `SingleDepositorVault` adds the following features over `FeeVault`:

1. **Direct deposits / withdrawals**. The vault owner can deposit / withdraw any ERC20 tokens.
2. **Execution**. The vault owner can use the vault as a wallet, retaining direct custody and the ability to execute with the vault's funds at all times.

We also provide a default fee calculator implementation `DelayedFeeCalculator` which should be used in conjunction with the `SingleDepositorVault`.

### Why it Matters

The `SingleDepositorVault` is can be used to support the following scenarios:

* **Treasury management**. A treasury could be managed with a `SingleDepositorVault`. In this sense the `SingleDepositorVault` is a direct upgrade over the Aera V2 vault allowing the same functionality but with a much more advanced guardian interface.
* **Complex integrations**. For example, creating a Yearn vault from an Aera vault could be done by using a wrapper over the single depositor vault and encoding owner actions. The recommended approach, however, would be to create a new type of vault that directly inherits from `BaseVault`.

### How to Use the `SingleDepositorVault`

**`deposit`**

Deposit requires you to specify an array of `TokenAmount[]` where each entry has a `token` (the deposit token) and `amount` (the amount to deposit). Each ERC20 token will be directly deposited and doesn't need to exist on a whitelist.

`withdraw` works analogously but for redemptions.

**`execute`**

This function allows the vault owner to execute arbitrary actions by passing an array of `OperationPayable[]` (with the conventional `target`, `data` and `value` arguments). Note that `execute` can also be used to transfer tokens out of the vault (among many other things).

No whitelist of actions or hooks are enabled on execute operations (unlike `submit` constraints for guardians).

### Caveats

Note that no tokens are withheld even if unclaimed fees exist in the vault during a `withdraw` or `execute` operation. The implicit trust model is that fees have to be claimed regularly by the fee recipient.