In response to feedback and approval from stakeholders in the mStable ecosystem, the genesis team have shipped a new and upgraded version of Save. Save v2 is a more composable, tokenised version of Save V1. This is achieved by creating an imUSD token that represents the yield accruing mUSD that can be transferred and used as collateral in other DeFi platforms. Save v2 will also offer users a chance to farm MTA with their imUSD with a completely new rewards streaming system.
This guide will take Save v1 depositors through a step by step migration process for their mUSD to move it safely to the new v2 contracts.
1. Save v2 support ships in the mStable App
On Monday 18 Jan 2021, a new version of the mStable App will be released, with support for Save v2.
2. Pre-deposit Save V1 into Save V2
Later that day, the Save v2 contract will be deployed and made visible in the app, but not yet activated (i.e. interest will still be paid to the v1 contract).
You can take the opportunity here to migrate your savings from v1 to v2 by following the simple migration assistant (pictured below). Three transactions will be required to complete the process.
This is optional, but the early bird gets the rewards-multiplier worm!
3. (Optional) Deposit your imUSD in the Vault and earn MTA rewards
In the v2 section of Save, there are a number of asset balances being displayed:
- Your mUSD balance
- Your imUSD balance (obtained by depositing mUSD as collateral)
- Your imUSD Vault balance (obtained by depositing imUSD in the vault)
- Your MTA balance
- Your vMTA balance (obtained by staking MTA)
The imUSD Vault acts as a deposit box to receive rewards in proportion to a deposited amount of imUSD and your vMTA balance. The vault determines a rewards earning power multiplier for each account of 1x to 3x.
You can use the earning power calculator to calculate the required vMTA for a given imUSD deposit (or vice-versa).
If you are already staking MTA, you can calculate the multiplier available for a given amount of imUSD.
If you aren’t staking yet and want to get in on the action, simply go to the mStable Governance App and stake; the Vault will read your vMTA balance.
4. The Save v2 contract is activated
To finalise the transition process, a governance transaction to direct interest to the Save v2 contract will be confirmed, at which point the App will display Save v1 as deprecated, and Save v2 deposits will start receiving interest.
@jronsim will say a few poignant words about the enduring strength of the human spirit, shed a single tear, and life in DeFi will move on.
5. Claiming rewards
The rewards system for the imUSD Vault provides a fair way to distribute rewards over time while alleviating spikes of claim volume.
There are four balances represented when claiming rewards:
Rewards earned but not yet claimed. The next claim will send 20% of these rewards to you now, and 80% to your ‘Vesting’ amount.
Rewards from previous claims that have vested. The next claim will send 100% of these rewards to you.
Rewards from previous claims that are vesting. When a new vesting period starts, these rewards will gradually move to your ‘Vested’ amount. The lockup period before this streaming starts is 6 months.
Simply your MTA balance.
As soon as you have deposited imUSD in the Vault (and rewards are being distributed), the ‘Unclaimed’ amount will start increasing.
You can press the ‘Preview Claim’ button to get an idea of what the effects will be.
Whenever a new claim is made, the vault creates a new vesting stream for 80% of the unclaimed amount. The rewards earned from a single claim may come from multiple streams if there are vested rewards.
You can also use Time Travel Rewards™ to preview the potential state of your rewards on a given date (note that this does make the assumption that the total distributed rewards are constant).
A note on APY at launch
Please note that an APY value won’t display for the new contract for a short while after launch, while mUSD-imUSD exchange rates are collected.
Thanks to James Lefrère who wrote the majority of this guide, any errors that remain are mine.