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Edelweiss Interop Recap

Posted by EF Protocol Support on February 7, 2023

Edelweiss Interop Recap

With The Merge now firmly behind us, protocol developers have been making progress across a (record?) number of areas over the past few months. Withdrawals, danksharding, EOF, verkle tries, history expiry, SSZ and more have all seen significant progress recently!

In order to help move each of these threads forward, and to run through one more series of Shapella stress tests, client team members gathered in person for a week-long interop event in Austria: Edelweiss šŸ”ļø

Unlike Amphora, which had a singular focus on The Merge, this event had two major tracks, focused on the Shapella and ProtoDanksharding network upgrades respectively. Several breakout sessions were also held to dive into other open problems. Here is a brief overview of what was accomplished, as well as links to artifacts from the workshops & ongoing discussion threads.


The week began with a Shanghai/Capella mainnet shadow fork. Flooding the network with withdrawal credential update messages revealed performance issues on the network, and led to a different consensus-layer queueing design to process these messages.

Throughout the week, additional devnets were launched and stress tested with large amounts of credential updates, withdrawals, and even bad blocks. Client implementations ended the week hardened and ready for the fork on the newly-launched Zhejiang testnet.

Assuming the Shapella upgrade happens without issue on Zhejiang, the Sepolia and Goerli testnets will be upgraded next!


The main EIP-4844 interop goal was the launch of an all-client EIP-4844 devnet. By Friday, all but one client were syncing on the network!

Several design discussions also took place during the week, stemming from a transaction pool design proposal. Questions around allowing "blobless" 4844 transactions, if and how blocks & blobs should be coupled for gossip and how to encode these transactions were discussed extensively and surfaced on last week's AllCoreDevs Execution Layer call.

Over the next few weeks, teams hope to finalize all spec changes resulting from these discussions and launch a new devnet.

EVM Object Format (EOF)

After having been conditionally accepted and then removed from Shanghai, EOF was one of the topics where opinions about the best path forward diverged the most.

Whether EOF should ban code introspection, aim for a minimal deployment ASAP, or even only ever go live on L2s were all discussed during the week.

No concrete specification came out of the workshop, but teams now have a shared understanding of the design space and potential paths forward. The EOF breakout rooms resumes next week to continue this conversation!

Everything Else

Aside from these three topics, teams discussed the future of light clients on the network, how the EL & CL specs processes could converge (and potentially carve out ERCs from other EIPs), launched a new Verkle Trie testnet, put forward a proposal to SSZ encode EL transactions, discussed changing the validator EL->CL deposit mechanics, and even started a Capella annotated spec!

Next Steps

Less than a week after the event, client teams have begun discussing Shapella timelines for testnets. Keep an eye out on this blog, as well as on clients' repositories, for announcements in the coming weeks!

For other efforts, such as EIP-4844, EOF, SSZ, expect to see active design discussions in the coming weeks, leading to prototype implementations afterwards.

Shapella is almost here, and Dencun is clear on the horizon šŸŒ…

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