Overview of sprint 107.​

Cardano Node 10.5.4​

We rolled out cardano-node-10.5.4 release.

Leios​

PR / Issue	Status
Mux Leios Simulation	merged
Mux egress prioritisation	in progress
Mux egress fairness	resolved

Ouroboros-Network​

PR / Issue	Status	Notes
StandardHash with NFData constraint	merged
Tracing Libraries	merged
[tx-submission robustness and testing enhancements][pr#5315]	in review
RNG handling in SRV lookups for public root peers	in review	contribution by Saviour Uzoukwu
cardano ping implemented with ouroboros-network	blocked

Documentation​

• docs: fix typos across documentation by Ronald Eddy Jr

Maintenance​

• release scripts
• [scrive: added patch level fragments][pr#52306]
• Updates index-state, removed srp

DMQ-Node​

PR / Issue	Status
SigSubmission v2	in review
Integration with cardano-tracer	in progress
[Set the correct magic field][pr#30]	merged
[Churn test][#5303]	in review

High level summary​

The SRE team continues work on Cardano environment improvements and general maintenance.

Some notable recent changes, updates or improvements include:

• Cardano-node 10.5.4 has been released and 10.6.2 has been pre-released and deployed to all IOE release and pre-release environments.

• New arm64 release artifacts and OCI images are now available with node 10.6.2 pre-release.

Repository Work -- Merged​

Cardano-mainnet​

cardano-mainnet PR#41:

• Sets cardano-node release to 10.5.4. The private IOG pools, IOGP{2..4} have been retired. All private relays have been stopped as well as the retired block forging pool machines. Includes various improvements with cardano-parts release v2026-02-12. See the PR description for additional details.

Cardano-parts​

cardano-parts release v2026-02-12:

• This release updates cardano-node release to 10.5.4, cardano-node pre-release to 10.6.2, cardano-db-sync pre-release to 13.7.0.0 and cardano-faucet to 10.6. Dijkstra network support has been added to process-compose, recipes and scripts. The demo and demo-ng scripts have been substantially improved for Protocol Version 11 intra-era hard fork support, Constitutional Committee key voting, DRep registration, and constitution adoption. Other miscellaneous improvements and fixes are detailed in the PR description.

Cardano-playground​

cardano-playground PR#53:

• Sets cardano-node release to 10.5.4, cardano-node pre-release to 10.6.2, cardano-db-sync pre-release to 13.7.0.0 and cardano-faucet to 10.6. Dijkstra network support has been added to recipes and scripts. The demo and demo-ng scripts have been substantially improved for Protocol Version 11 intra-era hard fork support, Constitutional Committee key voting, DRep registration, and constitution adoption. Includes various improvements with cardano-parts release v2026-02-12. See the PR description for additional details.

cardano-playground PR#54:

• Upgrades the cardano environment switching for recipes and scripts to a sourcing method instead of the prior GDB parent shell var modification approach which has become more fragile over time.

Cardano-node​

cardano-node PR#6424:

• Bumps cardano-node cabal version to 10.6.2
• Bumps iohkNix for 10.6.2 configuration updates (see iohk-nix PR#609 for details)
• Updates CI files for configuration changed in 10.6.2

cardano-node PR#6425:

• Bumps iohk-nix for 10.5.4 preview checkpoint file, peer snapshot and ledger updates
• Adjust CI files

Iohk-nix​

iohk-nix PR#609:

• Adds a preview checkpoint file
• Adds mempool timeout docs and bumps MinNodeVersion to 10.6.2
• Adds dijkstra network config
• Updates per environment peer-snapshot file and useLedgerAfterSlot
• Fixes mkConfigHtml function html spacing when using multi-line strings
• Sets mkConfigHtml to use new default tracing for the genesis file inclusion check
• Switches Dijkstra network to GenesisMode w/ peer-snapshot as default

Repository Work In Progress -- PRs and Branches​

• Cardano-mainnet: https://github.com/input-output-hk/cardano-mainnet/pull/42
• Cardano-node: https://github.com/IntersectMBO/cardano-node/pull/6410
• Cardano-parts: https://github.com/input-output-hk/cardano-parts/pull/79
• Cardano-playground: https://github.com/input-output-hk/cardano-playground/pull/55

High level summary​

• Continued work on Node 10.7 integration (Treasury Funding Initiative 17: Maintenance and Support):
  • Integrated network packages up to ouroboros-network-0.22.6 (#1819, #1865).
  • Integrated latest ledger changes (#1762).
  • Integrated kes-agent-1.1 (#1819) (Treasury Funding Initiative 9: KES Agent).
• Node improvements (Treasury Funding Initiative 17: Maintenance and Support):
  • Improved mempool behavior for local clients:
    • Downgraded hard timeouts to soft timeouts, improving user experience for wallets and other local client integrations (#1856, #1857, #1858).
    • Made it easier for downstream tracers to scrutinize mempool rejection details (#1847).
    • Enhanced observability by exposing the reason for chain switches in the ChainSel tracer (#1826).
  • Added support for the new GetDRepDelegations ledger state query in NodeToClientV_23 (#1794).
  • Fixed an exception due to a mix-up of resources in the V2 LedgerDB (#1842).
  • Minor: code cleanup (#1854).
  • Added documentation for the Consensus-Ledger interaction (#1830).
• Continued Leios prototype development (Treasury Funding Initiative 4: Ouroboros Leios Implementation, MS4.6):
  • Refactored to use EbHash instead of EbId for cleaner design (#1859).
  • Simplified to monomorphic types for more rapid iteration (#1846).
  • Implemented in-memory LeiosDb for ThreadNet tests (#1837).

High level overview​

This week, the Mithril team focused on implementing new succinct proofs. The team worked on pre-aggregation SNARK primitives in the STM library, completed golden master tests of the non-recursive SNARK circuit, and worked on bridging CPU and circuit implementations. They also began adapting the certificate chain for SNARK-friendliness.

Additionally, the team continued work on the new certification for Cardano blocks and transactions. This included implementing the signable builder, along with the artifact and proof routes in the aggregator REST API.

Finally, they worked on static builds for Mithril nodes and fixed bugs in the hash-to-curve implementation of the Schnorr signature.

Low level overview​

Features​

• Completed the issue Add golden tests for Halo2 circuit prototype #2912
• Completed the issue Pallas DMQ publisher keeps open connection to DMQ node #2961
• Completed the issue Implement artifact routes for Cardano Blocks and Transactions in aggregator REST API #2956
• Completed the issue Follower aggregator panics in e2e tests in run-only mode #2770
• Worked on the issue Implement SNARK pre-aggregation primitives in STM library - Phase 1 #2792
• Worked on the issue Compute Lottery Target Value for SNARK #2974
• Worked on the issue Hash to curve CPU/circuit discrepancy for message signature in Schnorr signature #2993
• Worked on the issue Implement signable builder for Cardano Blocks and Transactions #2908
• Worked on the issue Implement signing configuration for Cardano Blocks and Transactions #2971
• Worked on the issue Adapt certificate chain to support SNARK AVK #2811
• Worked on the issue Implement proof route for Cardano Blocks and Transactions in aggregator REST API #2988
• Worked on the issue Implement static build of Mithril nodes in CI #2989

Protocol maintenance​

• Worked on the issue Enhance protocol security page on website #2703

Overview of sprints: 103, 104, 105, 106.​

The most important changes are patches developed after the November fork incident on Mainnet, which make the diffusion layer more robust. These patches are released in the cardano-node-10.5.4 release. We highly recommend updating to 10.5.4 as these change make the Cardano Network more robust. We'd like to thank Karl Knutsson (CF) who developed these patches.

This report only contains issues/PRs finished/merged in the sprints 103 through 106. Work that has been carried and finished in the current sprint will be reported in the future.

Ouroboros-Network​

Diffusion​

• Optimised connectivity to peers behind firewall
• ChainSync timeouts:
  • no chain-sync StNext StMustReply timeout for trustable local root peers
• More robust diffusion A series of patches after the November incident:
  • enforce max reconnection attempts,
  • use shorter timeout when waiting on chain-sync to exit,
  • block-fetch: exclude peers that are shutting down in active peers calculation,
  • chain-sync: bumped StNext StMustReply timeout from a range of 135-269s to 601-911s.
• WASM support

Cardano-Ping​

• Unknown version received in cardano-cli ping

Leios​

• Network mux demo for analysing Leios/Praos traffic
• mux leios simulation

Technical Debt​

• Small changes
• fixed nightly build
• Removed duplicate trace events
• Fixed a typo

Cardano-Node​

• networking adjustments for the new tracing system

DMQ-Node​

• Signature verification
• Moved dmq-node to its own repo
• Enhance validation logic
• Mempool fixes: various bug fixes and code refactorings for the dmq-node.
• PeerSelectionPoolicy for dmq-node