Mean Bug Disclosure: Rounding on Swaps

The bug

  • Your position says you have 0.02194200 WBTC to withdraw
  • Pool owns 0.02194198 WBTC
  • Due to a 2e-8 WBTC (~ 0.0009244222 USD) difference on the pool balance, you won’t be able to withdraw from the pair (the withdraw will always revert as the pool doesn’t have enough funds for the payout)


  • 5AM (UTC) user reports bug
  • 1PM (UTC) team became aware of the bug report
  • 2PM (UTC) team became aware of the bug (swap rate precision)
  • 6.45PM (UTC) bug discovered — contingency plan created

What’s next?

  • For users that can be affected by this bug, we will monitor all pairs and match missing funds by creating our own positions, therefore allowing every user to withdraw their swapped funds. In case you are still not allowed to withdraw them please communicate with us through Bug Reports.
  • We will not urge to deploy a new version just for the sake of fixing this bug. Our plan is to add a few features that we had already planned for V2 and release a new version with the bug fix + features within the next 4 weeks.



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