In November 2025, we launched the Mesa Testnet, an intentionally unstable, pre-flight environment built to surface issues early, test new protocol features, and lay the groundwork for a safe and confident upgrade to mainnet.
Over the last month, the o1Labs engineering team has run structured testing across Mesa’s core features, generating real data and iterating quickly on the findings. These findings have directly shaped the codebase heading into Mesa Trail and given the team higher confidence in the upgrade path ahead.
Below, we’re sharing a full breakdown of the results from March:
Mesa Infrastructure, Tooling & Testing
The team completed a full review and update of documentation, alongside a comprehensive test plan for Mesa Trail, and wrote and validated automation scripts to support structured hard fork testing.
On the testing side, the team has run multiple dry run iterations with nodes upgrading in legacy and auto mode, as well as maximum load cluster tests to validate network behavior under stress. Other accomplishments include:
- Continued work on a dedicated Mesa Upgrade monitoring tool, giving the team real-time visibility into the percentage of active stake that has upgraded to the Mesa release.
- Optimized the packaging pipeline – reducing packaging time from 2 hours to just 22 minutes – a significant improvement to the efficiency of the hard fork process.
- 9 dry runs have been completed, testing across legacy and auto upgrade modes, different scenarios, configurations, and fixes. Dry runs 7 and 9 were company-wide, with multiple participants, varied levels of experience running nodes, multiple architectures, and setups across timezones to mimic a realistic upgrade scenario.
- Maximum load cluster testing, alongside secondary cluster testing, to allow complex test runs in parallel. One of the cluster tests revealed a glibc dependency issue, which has now also been fixed.
- Building and testing of Mina 3.4.0 release.
- Fixed an issue that could cause nodes to get stuck on startup in certain conditions.
- Triaged and resolved a node offline issue, determined to be environmental.
- Built and launched an explorer for Mesa with full block and transaction history for all networks.
Preparation is underway for a full dry run involving more users and nodes. This will launch after the code freeze and serve as the final validation step before Mesa Trail begins.
OCaml
At the protocol level, the OCaml workstream covered a wide range of fixes, improvements, and preparatory work. A key milestone was completing the automated hard fork mode, a significant improvement over the manual upgrade process used in previous upgrades.
The team also debugged and fixed average block time on the Mesa Testnet, and resolved a small but persistent memory leak in the Mina daemon related to libp2p helper code.
On the CI and release side, the team expanded cluster testing infrastructure to support more extensive runs, prepared the CI environment for the Mesa branch, and added a nightly automated build of the hard fork package to catch any issues early.
Releases:
Once the release candidate is ready, we will redeploy the Mesa Testnet, transitioning it into a stable environment that reflects the final Mesa configuration.
o1js
The o1js workstream made significant strides toward Mesa compatibility, with the headline deliverable to be the release of o1js 3.0, which enables full Mesa capabilities for o1js.
Alongside this, the team completed the full migration pipeline and end-to-end tests for upgrading zkApps from Berkeley to Mesa. Additionally, the new Mesa prerelease (3.0.0-mesa.0) has been successfully tested during dry runs, including the zkApp upgrade mechanism.
This, combined with updated examples in documentation, means developers will have a clear and tested path for upgrading their applications ahead of the mainnet upgrade.
Releases:
- 2.13.1
- 2.14.0
- Pre-released Native Prover 2.14.0-dev.bb172: compatible with o1js 2.14.0
- Pre-released o1js 3.0 Native Prover + Mesa: feature-complete prerelease combining Mesa changes and Native Prover
Next steps
With the Mesa Testnet phase close to completion, the focus will soon shift to Mesa Trail, the most collaborative stage of the Mesa journey so far.
Mesa Trail will begin from a Berkeley-like state and execute a complete upgrade to Mesa, exactly as mainnet will. Before it launches, the team will complete a final full dry run following code freeze, ensuring every component of the upgrade process has been validated end-to-end.
As part of Mesa Trail, we’re launching the Trailblazers Program — an incentivized initiative for a select group of experienced node operators, chosen to represent diverse geographies, hardware configurations, and deployment setups. In parallel, we’ll be inviting zkApp developers to deploy and test their applications.
In the meantime, developers are encouraged to explore the Mesa Testnet, experiment with the new capabilities, and join the conversation in the Mina Protocol Discord.
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.
