[DRAFT] Upgrade Proposal: Bedrock

Executive Summary

In short, what is this upgrade proposal?
Impacted stakeholders & expected outcomes
Why the Collective should upgrade

The Optimism Foundation is proud to propose the first protocol upgrade to the Optimism Collective: Bedrock. The Bedrock release of the OP Stack represents the culmination of years of research and development by the Ethereum scaling community and is a complete rewrite of the core components of the Optimism architecture. This upgrade offers a new level of modularity, simplicity, and Ethereum equivalence for Layer 2 solutions, providing unprecedented performance and functionality.

Most users will not be impacted by the upgrade as the current mainnet is already EVM-equivalent. Users and projects that run both full and archive nodes, make use of deposits and withdrawals, and make assumptions about the block time on Optimism Mainnet will need to take action to prepare for the upgrade. To help ensure a smooth transition, a thorough changelog and stakeholder-specific requirements can be found below.

In addition to these technical improvements, the Bedrock upgrade is a significant step towards the multi-chain future. By creating a shared standard, the OP Stack, Bedrock sets the stage for a Cambrian explosion of aligned L2s. This is an opportunity for leadership in the Ethereum ecosystem.

We are confident that the post-Bedrock experience will be a positive change for developers in the Optimism ecosystem and have received consistent excitement for the upgrade from our partners. We are committed to making this upgrade a success and are eager to see the results in the months and years to come.

Technical Summary

Overview of architectural changes
Link to all protocol/API/tech specifications
Overview of ongoing security considerations incl. all audits and findings

At the highest level, the Bedrock release implements a modular architecture, separating the OP Stack into 3 components: consensus, execution, and settlement. These designs borrow heavily from the Engine API introduced for the Merge, and, as a result, an Ethereum execution client can be converted into an Optimism execution client in <2,000 lines of code. This is a huge win, paving the way for a multi-client future, and allowing for maximal use of Ethereum’s battle-tested code.

Technical documentation for Bedrock is split into 3 main parts:

Additionally, a summary of the security measures and considerations for Bedrock can be found in this blog post by OP Labs, which includes links to security audits and testing measures. Notably, the Bedrock release introduces a 2-phase withdrawal process, doubling down on bridge security, which proved to be a primary risk factor for chains in 2022. There is also a community security contest currently live. This program provides strong incentives for high-severity bugs, so it’s possible that the program uncovers new findings. Results will be known on February 6, before any voting starts.

Impact Summary

Changes in performance characteristics
Time-of-upgrade considerations (downtime, etc)
Links to exhaustive upgrade documentation for impacted stakeholders

The Bedrock release enables performance improvements across the board, including transaction costs, throughput characteristics, and sync speeds. A detailed list of performance metrics for the release will be published by next week, with a link updated here when ready.

We estimate that the upgrade to Bedrock will take <4 hours. Unlike previous upgrades to Optimism, this release will not require a “regenesis,” and historic chain data will still be accessible after the upgrade. As such, little action is required from end-users of Optimism other than being aware of that timing, during which deposits and transactions will be paused.

While the upgrade strictly improves on EVM equivalence, some application developers may be affected. While we have been in active touch with major partners, the developer community has also been actively notified over the past few months in 1:many communications. We maintain the following documentation pages for impacted developers:

Action Plan

Mainnet Upgrade Timing
Contingency plans in case of last-minute bugs or issues
Plan for communication and education to the community

If this vote passes, the Bedrock upgrade will be scheduled for execution 2 weeks after the vote passes, on March 15, at 9:00 AM PST.

The upgrade overview documentation page describes mechanically how the upgrade will be executed if approved by the Token House, and the code here implements the migration logic from the old chain to Bedrock.

Optimism’s Goerli testnet has already been successfully upgraded, with major partners following suit, without significant setbacks. However, in the event that substantial new information comes to light between a successful vote and execution of the upgrade, this proposal includes two fallback scenarios:

  • In the event that a specific application has not prepared for the upgrade, and doing so would pose significant risk of end-users being negatively misled, then we will delay the execution of the upgrade by approximately 1-2 weeks in order to provide additional preparation time.
  • In the event that a significant, new security risk is discovered, we may cancel the upgrade, requiring a new vote once the community has had time to react.

The Optimism Foundation and OP Labs will continue public communication efforts around the upgrade, including public communications and tweets reminding stakeholders of the upgrade in the weeks, days, and hours leading up to the upgrade.


This proposal outlines the Optimism Collective’s first Protocol upgrade of Optimism Mainnet to the Bedrock release. This upgrade aims to provide unprecedented modularity, simplicity, and Ethereum equivalence to the L2 network, with positive impacts on performance and security. Bedrock is the codebase which will help Optimism stand the test of time, and is also preparatory step towards the multi-chain future.

We expect the upgrade will take around 4 hours, with no loss of historical data. Detailed technical specifications and impact summaries are available for the upgrade.

We strongly believe that the Collective should upgrade Optimism Mainnet to the Bedrock release, take advantage of the benefits it brings, and to continue to play a leadership role in the scaling community.

For any further questions or concerns, we will be hosting an AMA on February 8th at 18:30 GMT in Discord to go over the proposal with team members from the Optimism Foundation and OP Labs.


This is so exciting to read, and I think the potential this could unlock - if all goes to plan here - is tremendous for enabling global adoption. This potential here of mass on-boarding…perhaps for the first time becoming real.

Looking forward to following the progress!


The upgrade guide is a very nice way to explain exactly what is happening through the hard fork and find the process very intriguing.
We will make sure our community is aware of the upgrade prior to the event.


what a fantastic moment in Ethereum scaling history- I’m excited beyond belief and incredibly grateful for the team pouring energy into co-ordinating this reality. values win, persistence is key.


good,Looking forward to following the progress!


A milestone, congrats to the OP Labs and OF teams! I’d recommend information about and links to third-party audits being in the main proposal itself; instead of being behind a link - as it is critical information.


A beautiful read it is :pushpin: LFG


Congratulations on this, very detailed information; looking forward to the AMA!

Have we already identified the main applications that will need to be prepared before the upgrade? or what is the procedure for the specific team of an app to inform and alert the need to prepare or be in communication with the OP labs/foundation team. Thank you


Congratulations OP is getting better and better, the project side is doing things very honestly, change the world human!!!


Go Optimism, Go Bedrock


Huge upgrade, can’t wait this to go live.


I think This Proposal is obvious


I don’t see any L2’s near Optimisms tech with the bedrock upgrade, as far as optimistic rollups go, OP sure is leading the pack.


This upgrade will change the game. I love how Optimism team working and how the community helping.


Very good very nice.


Wow, I’m so happy to see this upgrade. :red_circle: :sparkles:

Congrats to OP


We are in support of this and appreciate the information and links provided within this post.

I’d recommend making some of the information in those links more front-facing in the main post, such as the summary of the Bedrock Explainer and Security & Audits.


Well, such a move is democratic.

1 Like

Good proposal, the Collective should upgrade Optimism Mainnet to the Bedrock release. I hope the community will accept this too.

1 Like

this update is tremendous, keep it up

1 Like