Temp check, to see how much interest there is in this.
Overview
Given the improvements coming to Polygon POL staking in PIP-69, I propose we should further refine the staking implementation by creating a ERC-7575 vault . This could either be enshrined with official contracts, or managed with competition by third parties who want to build on Polygon.
Motivation
Given the current ~100 validators currently listed as currently validating and staking with POL, PIP-69 would create 100 different ERC-20 tokens. While they are each fungible (a massive improvement to POL staking) its still fragmented liquidity that could be brought together under a single staked POL liquid token.
Implementation
EIP-7575 does not assume value parity of input assets (in this case, various ERC-20s representing staked POL on each validator). Valuing each input token is up to the implementation, and may require an active curator for the vault because the native share tokens themselves encode the stake and reward balances, the LST contract’s job becomes bookkeeping, rather than the heavy lifting of managing actual staking operations.
EIP-7575 does not enforce that different assets must be of equal value, or come in at a fixed 1:1 parity. Instead, how many shares you get when depositing depends entirely on how the vault or implementation defines the conversion between that asset and the share token via convertToShares. That conversion can (and typically will) reflect market value, risk, or other internal logic. In our implementation of a 7575 vault it may need to reflect the yield and slashing risk of various staked POL tokens depending on which validator it is staked with.
The next stage of an enshrined vault would be a cross chain messaging layer that can mint the POL LST on Polygon, Katana, or other aligned chains.