DeFi Meme Coin YAM Succumbs to Fatal 'Rebase' Bug, Makes Plans for 'YAM 2.0'

DeFi meme coin YAM has lost control of its on-chain governance feature following a reported bug.

Aug 13, 2020 at 8:33 a.m. UTC
Updated Sep 14, 2021 at 9:43 a.m. UTC

UPDATE (Aug. 13, 08:57 UTC): In the last few moments, the YAM project has said it is planning on launching a new version in a "post-rescue attempt."

  • DeFi meme coin YAM has succumbed to a bug within its rebase function, meaning the coin has lost control of its on-chain governance feature.
  • All of the roughly $750,000 Curve tokens stored in the project's treasury are lost as well, according to a Medium blog from the team.
  • Launched Tuesday, YAM had $585 million assets under lock as of 4:30 UTC. 
  • YAM’s code contained a bug that issued “excess” rebase supply to the token’s treasury.
  • The bug made the project’s on-chain governance feature unusable.
  • A possible fix slipped through the cracks early Thursday morning. Yam Finance co-founder Brock Elmore voiced his regret in a tweet.
  • In an ensuing blog post, YAM said it is drawing up plans to launch a new version of the yield farming protocol – presumably without the rebase bug in the codebase.
  • The team will gauge community interest by setting up a funding goal; if reached the team will develop a migration contract porting the ecosystem onto a new protocol.
  • A yield farming protocol, the project was supposed to use rebases to adjust supply in order for the token to maintain parity to the U.S. dollar.
  • The project's rapid surge in user numbers came from the fact it offered features DeFi yield farmers were hunting for, combined with an instantly recognizable symbol in the shape of the yam emoji.
  • But its relative newness means the code had not yet been audited.
  • In a post-mortem, the team said even though they thought they had enough votes to save the protocol the bug prevented the proposal from succeeding.


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