A user opened a ticket in the Revoke discord today. Their sDAI balance isn't showing up. So I decided to dive in: turns out that sDAI is deliberately not emitting Transfer events on mint/burn of the token. This puts an unnecessary strain on the rest of the ecosystem.

The sDAI contract implements ERC-4626, a standard for single-token vaults. This standard specifies to emit Deposit/Withdraw events on mint/burn of the vault token. But it does not prohibit developers from ALSO emitting Transfer events.

The Spark docs mention that they deliberately do not emit Transfer events on mint/burn to save gas in these transactions. I would argue that the added integration burden on the rest of the ecosystem is far more costly than the bit of gas savings this achieves.

Contrast sDAI's idealogical approach to Yearn's pragmatic approach. Yearn v3 Vaults are also ERC-4626 compliant, but still emit Transfer events so that they are easily integrated into wallets, explorers and other tools.

It appears that Spark agrees that removing Transfer events was a mistake, since the newer sUSDS token DOES emit Transfer events on deposit/withdraw. With that in mind, I hope that future ERC-4626 vaults continue to follow this more pragmatic approach.

What does this mean for Revoke? Your APPROVALS will ALWAYS show up correctly. But we might not be able to display your sDAI *balance* if you've only ever minted it. Once you've made other sDAI transfers, then your balance will show up as usual.