> For the complete documentation index, see [llms.txt](https://cardanoupgrades.docs.intersectmbo.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cardanoupgrades.docs.intersectmbo.org/general/hard-fork-working-group-meeting-minutes/21st-may-2026.md).

# 21st May 2026

#### Agenda

1. [Action items from the last call](https://cardanoupgrades.docs.intersectmbo.org/van-rossem-upgrade/hard-fork-working-group-meeting-minutes/19th-may-2026#action-items-and-next-steps) - Bosko
2. [Node 11.0.1](https://github.com/IntersectMBO/cardano-node/releases/tag/11.0.1) & [DBSync 13.7.0.5](https://github.com/IntersectMBO/cardano-db-sync/releases/tag/13.7.0.5) - Sam/Ramsay/Jeff
   1. [Notice: epoch aggregate values issue in db-sync 13.7.0.x](https://intersectmbo.org/news/notice-epoch-aggregate-values-issue-in-db-sync-13.7.0.x)
3. [Van Rossem Upgrade Update](https://docs.google.com/presentation/d/1pEFh_GC3Nx2nTVPXj9bke9R7C9Bkr8Hk/edit?slide=id.p1\&pli=1#slide=id.p1) - Bosko, all
   1. Ogmios [PR](https://github.com/CardanoSolutions/ogmios/pull/461)
      1. van Rossem only support vs van Rossem & Dijkstra support
   2. Kupo [PR #1](https://github.com/CardanoSolutions/kupo/pull/203) & [PR#2](https://github.com/CardanoSolutions/kupo/pull/204)
      1. Potential alternative path to progress without explicit need for Ogmios? - Sam
   3. [Readiness tracker](https://docs.google.com/spreadsheets/d/1ECoYFCtrRtFX3BvqfhaZi6FxlXQMoTGP/edit?usp=sharing\&ouid=106134819668558877362\&rtpof=true\&sd=true)
4. van Rossem hard fork progress - Bosko
   1. PreProd
      1. [Cardanoscan](https://preprod.cardanoscan.io/govAction/gov_action108a5htqnmlp89ffn2ucf7u9u33s0r9gpx7eytpdc2q28y50ly42qqf9jcen)
      2. [Cexplorer](https://preprod.cexplorer.io/gov/action/79fb4bac13dfc272a53357309f70bc8c60f1950137b24585b850147251ff2554%25230)
      3. Are we ready to vote, ratify and enact hf ga on preprod? (first next possible enactment date is **26st May** if its voted for until **21st May** - epoch boundary on PreProd)
   2. Mainnet
      1. Are we on the track to submit it on **29th May**? (if PreProd is not forked on 26th May, hf ga submission on mainnet will be delayed for at least an epoch)
5. Plutus Cost Model - Kevin, Ryan, Bosko
   1. PreProd - submitted, ratified, was enacted at the epoch boundary on **16th May**
   2. Mainnet - expected to be submitted today
      1. expected to be followed by mincommittee size action an epoch later
6. van Rossem comms - Ian / Larisa
   1. Comms plan - CF, Midnight, Shielded, Emurgo, Intersect, IO
      1. Weekly comms meeting
   2. Comms in the last week - anything we missed
   3. Comms in the week ahead
7. [Risk log](https://docs.google.com/spreadsheets/d/1DSAiayrPOhhzSKKKljbd2WxHQPFmzKsvoyyA-BJUDg8/edit?gid=1105903724#gid=1105903724)
8. AOB

#### Key materials

* Summary
  * DBSync issue from 20th May, with inflated values being written to epoch.out\_sum and epoch.fees at the first epoch boundary following a restart, rollback, cache miss, or upgrade, have been addressed - blog available [here](https://intersectmbo.org/news/notice-epoch-aggregate-values-issue-in-db-sync-13.7.0.x)
  * Ogmios PR hasnt been raised yet, and having in mind its considered to be the critial tool, hard fork working group didnt recommend ratification and subsequently enactment of the hard fork initiation governance action on Cardano PreProd testnet
  * That also means that the submission of the hard fork initiation governance action on mainnet cant happen as its originally planned on 29th of May (at that moment, PreProd wouldnt be forked yet)
  * First next possible date for PreProd hard fork governance action ratification is 26th May and enactment would happen on 31st May and therefore mainnet hard fork governance action submission can potentially happen as early as 3rd June
  * Criteria stays the same though, Ogmios van Rossem compatibility proper PR raised that gives certainty that there is a path ahead to fully working solution
  * It was noted and emphasized that [the readiness tracker](https://docs.google.com/spreadsheets/d/1ECoYFCtrRtFX3BvqfhaZi6FxlXQMoTGP/edit?usp=sharing\&ouid=106134819668558877362\&rtpof=true\&sd=true) should be updated with the certain thresholds for nodes running latest stable version 11.0.1 (50%), top 20 dapps, top 20 ecxhanges by liquidity, etc. That would also bring additional confidence layer for a decision to submit hard fork initiation governance action on mainnet
  * Risk log is to be updated with the latest findings on Ogmios readiness and will also have a new item on DBSync v13.7.0.5 on exchanges
  * Upon determining the Ogmios PR status and future recommendations when it comes to DBSync v13.7.0.5, specific comms piece is aimed to be sent out on Friday, 22nd May
  * Plutus Cost model parameter update governance action is expected to be submitted on mainnet later today or early tomorrow, 22nd May
  * Hard Fork working group will continue to assess van Rossem upgrade readiness every day, in and out of the scheduled working group meetings
* Hard Fork Working Group communication channels
  * [Discord](https://discord.com/channels/1136727663583698984/1242097284619960411) — `#wg-hard-fork`
  * [Weekly bulletins](https://x.com/IntersectMBO)
  * [Luma calendar](https://luma.com/calendar/cal-TMjYNpSY4huYYif)
* [van Rossem Upgrade Update](https://docs.google.com/presentation/d/1pEFh_GC3Nx2nTVPXj9bke9R7C9Bkr8Hk/edit?slide=id.p1\&pli=1#slide=id.p1)
* [van Rossem readiness tracker](https://docs.google.com/spreadsheets/d/1ECoYFCtrRtFX3BvqfhaZi6FxlXQMoTGP/edit?usp=sharing\&ouid=106134819668558877362\&rtpof=true\&sd=true)

#### **Action items and next steps**

* **Jeff:** Determine the Ogmios PR status by Friday, 22nd May and inform the hard fork working group
* **Jeff:** Check and confirm on future recommendations when it comes to DBSync 13.7.0.5 (context of the issue raised on 20th May)
* **Bosko:** Update van Rossem risk log with the latest findings on Ogmios readiness and a new item on DBSync v13.7.0.5 on exchanges
* **Ian/Larisa:** Send the specific comms piece as soon as possible upon determining the Ogmios PR status and future recommendations when it comes to DBSync v13.7.0.5


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