Heimdall version v0.12.1 has been released. This is a mandatory upgrade that introduces the Lugano hardfork.
Node operators running version v0.11.0 or older must upgrade, as their nodes will stop syncing at the Lugano activation height. The hardfork is already live on both Mainnet and the Amoy testnet.
Lugano Activation Blocks:
- Mainnet: block `54,627,000`
- Amoy: block `47,105,000`
This release contains crucial consensus-layer security fixes which are enabled by the hardfork, including:
- Validation hardening for bor, clerk, and milestones.
- Resource limits for block-sync serving.
- Adjustments to checkpoint window bounds.
Additionally, the release updates key dependencies to cometbft `v0.3.9-polygon` and cosmos-sdk `v0.2.15-polygon`.
Heimdall `v0.12.1` is the public counterpart of the private `v0.12.1-priv` release that delivered the **Lugano hardfork**, already activated on both networks: - Amoy: block `47,105,000` (2026-09-23) - Mainnet: block `54,627,000` (2026-10-01 16:22 UTC) Node operators still on `v0.11.0` or older stop at the Lugano height. Upgrade to `v0.12.1` and restart. The release contains consensus-layer security fixes gated at the Lugano height (checkpoint window bounds, block-sync serving resource limits, bor/clerk/milestone validation hardening), plus the matching dependency bumps: - cometbft [`v0.3.9-polygon`](https://github.com/0xPolygon/cometbft/releases/tag/v0.3.9-polygon) - cosmos-sdk [`v0.2.15-polygon`](https://github.com/0xPolygon/cosmos-sdk/releases/tag/v0.2.15-polygon) ## What's Changed * v0.12.1 candidate (Lugano) by @lucca30 in https://github.com/0xPolygon/heimdall-v2/pull/652 **Full Changelog**: https://github.com/0xPolygon/heimdall-v2/compare/v0.11.0...v0.12.1