Introducing Celo’s Gingerbread Hard Fork 🍞 (join for Q&A on June 21)

:bread::bread::bread: Gingerbread Hardfork :bread::bread::bread:

Dear Celo community, dear validators and node operators,

As announced in the beginning of the year in the Celo Roadmap Post as well as a more specific outline of the H1 2023 Roadmap for the Blockchain Team (forum post here), we at cLabs have been working to achieve

  1. Deep alignment with the Ethereum roadmap
  2. Horizontal scalability by making Celo an incredibly rollup-friendly chain
  3. Making Celo the fastest EVM L1.

With the Gingerbread Hardfork the blockchain team is delivering both on 1. Ethereum Alignment and laying the groundwork for 3. Increasing Speed. (Note that the Blockchain team has been working on pre-compiles, which is part of goal 2, separately).

Goals & Features

There are a number of changes in this Hard Fork, which broadly follow three different targets. A high level overview follows here. A technical overview can be found on github, where also technical details are presented.

1. Ultragreen Money: Boosting Celo’s positive impact on the planet by increasing carbon offsets

As discussed in a few places (1, 2, 3), we are introducing Ultragreen Money, which means that a part of the transaction fees will be used for carbon offsets natively on chain. This requires a Hard Fork, so that gas fees are sent to the newly created Gas Fee Handler Smart contract, from where they will be relayed to different usages.

2. Ethereum Alignment: Reduce code diff from Ethereum Client

Reducing the code diff to upstream geth is important to simplify maintenance of the Celo client and increase the compatibility of Celo with Ethereum and other EVM chains.

We achieve this with the following items: We propose to change some opcodes (restore opcode gas costs from Ethereum, add gaslimit opcode), re-add header fields with values used in Ethereum 2.0, and add bas_fee to the header.

3. Ethereum Alignment: Remove unused Celo-specific Features

A number of features that are specific to Celo have seen barely any usage (as is expected when shipping many features). However, they make it more complex to maintain the Celo client code, and can introduce issues when porting over DApps or tooling from the EVM space to Celo. Therefore, we propose to remove a number of features with this Hard Fork.

Specifically, we propose to remove Tobin Tax, minimum client version, freezable check on epoch rewards, full node incentives and the option that community rewards go to the reserve if it is undercollateralized.


We are currently working with the following timeline:

  1. June 16: Code complete for all HF features
  2. June 21: Baklava release published
  3. July 3: Baklava upgrade date
  4. July 14: Mainnet release published
  5. August 18: Hard Fork date

All Core Devs Call & Validator Q&A

Historically, we’ve had two type of calls where we discuss CIPs: The All Core Devs Call and the Validator Q&A session. We will combine these two this time and have two calls to accommodate people around the world. We will post the details on how to join the calls here shortly.

Currently planned schedule (subject to change: check Celo Signal public calendar for latest details):

  • Call 1: June 21, 2023, 5pm CET, 8am PT
  • Call 2: June 21, 2023: 2pm SGT, 10am GST, 8am CET

Call for Validators to update Contact Information

We ask all validators to fill out this form with their updated contact information so we can reach our directly via email, TG, etc. as well. Thank you so much!!

We’re looking forward to your feedback, both here as of now, and in the calls on June 21.


For the blockchain team


Hi @matt

Great work on improving Celo network.

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thanks for the feedback - access to form should be solved now

Is there an update on the status of this? Has the Baklava cut been released?

1 Like

The Baklava release was just made: please see this separate forum post.


Hii @matt
Thanks for sharing