Over the past months, the o1Labs engineering team has been preparing for the next Mina hard fork — the Mesa Upgrade. Today, we’re happy to share that Mesa moves into its next phase this fall, as the hard fork process is officially underway. With the Mesa Testnet now live, we’re transitioning from planning and development to execution and delivery — the first visible step in a carefully staged path towards mainnet. This also marks when the entire Mina community can actively take part in testing, validating, and shaping the future of the protocol. To set expectations clearly, Mesa Testnet is an intentionally unstable, pre-flight environment designed to surface issues early. This testnet will be bumpy — and that’s exactly what it’s for.
The Mesa Upgrade: From Design to Launch
Mesa represents a major step forward for Mina. It introduces several protocol-level improvements designed to expand the network’s capacity, optimize performance, and give developers greater flexibility when building zkApps.
To reach mainnet safely and confidently, this upgrade follows a multi-phase process — moving from proposal validation to community voting, followed by rigorous testing and final activation. Each phase will build on the one before it, ensuring that by the time we upgrade mainnet, every component has been tested and verified.
Mesa Testnet Is Live!
The Mesa Testnet marks the official start of the hard fork testing and implementation process — and we invite developers, node operators, and the broader community to join us in testing the new functionalities. We have set up a dedicated channel in the Mina Discord server for anyone interested.
This testnet is a pre-flight environment — intentionally unstable and not optimized for long-running reliability. It exists specifically to shake out bugs, validate assumptions, and pressure-test the new Mesa features in real conditions. Because early feedback is critical, we are opening the Mesa Testnet as soon as possible — even before a code freeze and full stability — so community members can begin experimenting with reduced slot time, expanded account-update limits, and other Mesa improvements right away.
This is where we begin validating everything that will define Mesa’s improvements, from higher limits on zkApp account updates to reduced slot time, and ensuring these changes maintain protocol stability and operations of Mina’s ecosystem of node operators.
You can find the full breakdown of the testnet phases in the Mesa Testing Plan blog.
The Road to the Hard Fork
As we progress through testing, several key milestones will guide us toward the upgrade. The Mesa Upgrade timeline (see below) outlines each stage and the necessary steps — from the ongoing testnet to the final hard fork.
This version of the timeline shows the full set of workstreams and checkpoints. At the time of publishing this blog post, only the On-Chain Vote (OCV) period dates are confirmed.
Each checkpoint on this timeline represents a decision point where the o1Labs team evaluates readiness and confirms the next step. Progressing through these checkpoints will not only mark tangible technical achievements but also provide increasing confidence and visibility into the final hard fork date. These include:
- Stake Snapshot for Voting (Nov): Capturing the eligible voter set ahead of the on-chain vote.
- On-Chain Vote (Dec): Community governance to approve the Mesa MIPs
- Mesa Trail Go/No-Go: A readiness review following the Mesa Trail preparation phase to confirm this testnet will go ahead following the holidays.
- Code Freeze: Locking in the release branch and finalizing the Mesa Upgrade codebase.
- DevNet Go/No-Go: Final testing of the upgrade path in a Devnet environment to verify hard fork readiness and release packaging.
- Mainnet Go/No-Go: The last checkpoint — the final approval before the mainnet upgrade is scheduled and executed.
As we progress through the Mesa Testnet and the initial phase of cluster testing, we will share more precise timing for the remainder of the upgrade. It will be at that point that we will publish an updated version of the timeline — including months and more specific dates.
At every checkpoint, o1Labs is committed to sharing transparent updates so the community can follow the journey and see how Mesa is advancing toward mainnet.
Image link to enlarge.
Community Governance: On-Chain Vote (OCV)
A central part of the Mesa process is the upcoming On-Chain Vote, happening Dec 8-15, where eligible community members will have the opportunity to vote on the protocol changes included in the upgrade.
This on-chain governance event represents another proof point toward Mina’s true decentralization, where core protocol improvements are validated not just by the engineering team, but by the community itself.
Details on voting eligibility, timing, and how to participate are outlined in the OCV announcement blog.
Beyond Mesa’s Horizon…
The Mesa Upgrade is well underway — with a live testnet, a roadmap of workstreams, and community participation at every stage.
Over the coming months, we’ll continue to share progress at each checkpoint — and we encourage developers and node operators to keep experimenting on the Mesa Testnet as features stabilize. Early testing is invaluable, and your participation helps ensure a smooth and secure upgrade to mainnet.
Mesa is just the start. The next horizon for Mina is already coming into view.
About Mina Protocol
Mina is the world’s lightest blockchain, powered by participants. Rather than apply brute computing force, Mina uses advanced cryptography and recursive zk-SNARKs to design an entire blockchain that is about 22kb, the size of a couple of tweets. It is the first layer-1 to enable efficient implementation and easy programmability of zero knowledge smart contracts (zkApps). With its unique privacy features and ability to connect to any website, Mina is building a private gateway between the real world and crypto—and the secure, democratic future we all deserve.
