Motivation
Burning of the stETH underlying shares is one of the on-chain effects causing stETH token rebase. We’d like to have all token rebases logged. It’s a good thing to have in general. In particular, it would allow not to miss a rebase for the off-chain interactive UIs and to sync on-chain storage change with 3rd-party off-chain indexers and monitoring.
Solution
We propose to include StETHBurnt event into the StETH contract and emit the proposed event on every burnShares invocation. The event must include information about the caller account, burnt shares amount and the corresponding amount of tokens burnt. It would allow to complete off-chain logs and hold a new invariant for Lido: every stETH token rebase must be covered with the some explicitly emitted event.
Specification
Further details and code example are provided on the LIP GitHub repo.