CANTON 3.4 TO CANTON 3.5 TRANSITION

1. #1Amanda Martin23-05-2026source ↗
   Update: 2026-05-22
   See details in the long-term SV Operations schedule
   
   Phase 1: Complete
   
   Phase 2: Splice 0.6.x Release line. Splice 0.6.x begins to introduce features from Canton 3.5 as part of the standard bundle. Protocol-breaking changes remain behind feature flags.
   

   • Proposal for Logical Synchronizers, and details of the first Logical Synchronizer Upgrade, is live at cip-discuss
   • Practice LSU on DevNet: 2026-06-03. Requires Splice 0.6.5 at minimum. Could require a higher version.

   
   Other Major Events for Splice 0.6.x:
   

   • Daml Models from Splice 0.6.2 take effect on the following dates. Requires Splice 0.6.2 at minimum:
     • DevNet: 2026-05-19
     • TestNet: 2026-05-26
     • MainNet: 2026-06-09

   
   Phase 3: Upgrade Global Synchronizer networks to Canton Protocol 35
   

   • All three Global Synchronizer networks will perform a Logical Synchronizer upgrade to Canton protocol Version 35.
   • Splice Version for this Upgrade: Splice 0.6.5
   • Dates:

   • LSU from protocol version (PV) 34 to 35 on DevNet: 2026-06-10
   • LSU for PV 34->35 on TestNet: 2026-06-17
   • LSU for PV 34->35 on MainNet: TBD based on results of SV discussions and Tech & Ops call on June 1st.

   • Specific Canton 3.5 features to be included in the LSU will be announced via release notes;  currently in final review.

   
   App Provider Experience during LSUs:
   

   • All party onboarding, package vetting and other topology transactions will pause for 24 hours before the LSU, and will resume immediately after the LSU completes.
   • Daml transactions will be delayed for seconds to minutes at the moment of the LSU
   • App providers should experience no other impact.