snapshots 0.2.0

# snapshots

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<p align="center">
    <img src="https://raw.githubusercontent.com/saber-hq/snapshots/master/images/banner.png" />
</p>

Voting Escrow Snapshots: Historical snapshots of previous voting escrow balances.

## Motivation

There are several instances in which one may want to use an instantaneous snapshot of all vote escrow balances, for example:

- **Fee distribution.** One may want to send protocol revenue to veToken holders.
- **Airdrops.** One may want to send tokens to holders of a veToken.

## Mechanism

veToken balances are recorded for every `period`. A period is recorded for every 3 days.

There are two accounts that are used to compute historical balances:

- [LockerHistory], which stores the total number of veTokens for each period, and
- [EscrowHistory], which stores the veTokens in each Escrow per period.

Any time someone refreshes and/or modifies their vote escrow, they should refresh their [EscrowHistory] accounts.

## Program Addresses

- **[snapshots]:** [StakeSSzfxn391k3LvdKbZP5WVwWd6AsY1DNiXHjQfK](https://anchor.so/programs/StakeSSzfxn391k3LvdKbZP5WVwWd6AsY1DNiXHjQfK)

## License

The [snapshots] program is licensed under the Affero General Public License version 3.