HPP Node 3.11.4 (Arbitrum Nitro)

What's Changed

• Docker image upgraded to Arbitrum Nitro v3.11.4
• Node config templates now use node.da.anytrust instead of the deprecated node.data-availability

ArbOS 61 (Elara) Upgrade

Conduit will activate ArbOS 61 (Elara) on the HPP chains on the dates below. Nodes running a Nitro version older than v3.11.3 will stop syncing after activation.

Network	Upgrade your node before
HPP Sepolia	Thu 8 Oct 2026
HPP Mainnet	Thu 15 Oct 2026

This schedule is subject to change. Upgrading early is safe: Nitro v3.11.4 keeps syncing the chain both before and after ArbOS 61 is activated.

Note: If you are running an external node, you must upgrade to this version before the dates above. Your existing data directory is upgraded in place — no new snapshot is required:

git pull
docker compose -f docker-compose.yml pull
docker compose -f docker-compose.yml down -t 300
./manage.sh run mainnet

For Sepolia, use docker-compose.sepolia.yml and ./manage.sh run sepolia.

What's New in ArbOS 61

• Gas refund fixes — fixes two interacting bugs in the gas refund logic that caused small, unintended changes to gas refund behavior. Applies to every chain that upgrades to ArbOS 61.
• WASM compatibility changes — includes several Stylus bug fixes and removes support for the WebAssembly multi-value extension. Stylus contracts that rely on multi-value WASM can no longer be activated or reactivated.
• Priority fee collection (optional) — chains can now collect tips as priority fees. Users could always set a priority fee, but it was ignored until now.
• Compliance transaction filtering (optional) — protocol-level filtering against an external policy service, applied at the sequencer and in the State Transition Function, including transactions submitted through the Delayed Inbox.

The optional features are enabled per chain and are not turned on as part of this upgrade.

For the full list of changes, see the ArbOS 61 Elara release notes.

Before You Upgrade

• The upgrade is one-way. Once a database has been opened by Nitro v3.10 or later, it can no longer be used with v3.9.x. Back up your data directory first if you need a way back.
• Update your node config. hpp-<network>-node-config.json is generated locally and is not changed by git pull. In that file, move the node.data-availability block under node.da.anytrust:

  -    "data-availability": {
  -      "enable": true,
  -      "rest-aggregator": { "enable": true, "urls": "..." }
  -    }
  +    "da": {
  +      "anytrust": {
  +        "enable": true,
  +        "rest-aggregator": { "enable": true, "urls": "..." }
  +      }
  +    }

  The old keys still work in v3.11.4, but the node logs DEPRECATED: --node.data-availability.* flags are deprecated at startup. Alternatively, re-run ./manage.sh init <network> to regenerate the config from the updated template (this overwrites any manual edits).
• Always stop the node with docker compose down -t 300 so it can flush its caches before exiting.

Full Changelog: v3.9.8...v3.11.4