Logical Synchronizer Upgrades 76 Milestone 4: Successful upgrade on MainNet

Milestone 4: Successful upgrade on MainNet

| Estimated Delivery | Month 6 | | :---- | :---- | | Focus | MainNet Physical Synchronizer, and at least 90 percent of Validators, successfully upgrade, retaining all history and cryptographic evidence, while halting Daml transactions for less than three minutes. |

Deliverables:

• Upgrade MainNet to a new version of Canton containing at least one protocol change.
• Successfully upgrade MainNet a second time to a new version of Canton containing at least one protocol change.
• Resolve any issues that come up in these upgrades.

Operational Handover & Ongoing Maintenance

Upon the successful completion of Milestone 4, day-to-day maintenance of the ISS-based BFT repository (including security SLAs, bug fixes, CI/CD pipeline management, and external PR reviews) will seamlessly roll into the purview of Digital Asset’s proposed 2026-Maintenance Grant for Daml Open Source.

_Originally posted by @pedrodneves in https://github.com/canton-foundation/canton-dev-fund/issues/76#issuecomment-4306170544_