[Standard] Ethereum - Mainnet and Testnets - Upgrade to Nethermind v1.39.3 and Reth 2.5.1

Scheduled for Aug 27, 09:00 - 15:00 UTC

Scheduled

We are upgrading our Ethereum Mainnet ad Testnet infrastructure to Nethermind v1.39.3.

This is a mandatory patch release addressing critical reliability and hardening fixes across block processing, networking, and request decoding. No consensus or database-format changes are included.

During the maintenance window, brief interruptions to RPC availability may occur.

https://github.com/NethermindEth/nethermind/releases/tag/1.39.3

Posted Aug 20, 2026 - 18:56 UTC

This scheduled maintenance affects: Ethereum (Mainnet — JSON-RPC API, Sepolia — JSON-RPC API, Hoodi - JSON-RPC API).