ethrex, the Ethereum execution client built by Lambda, has completed six months in mainnet production. It is run by three professional node operators and has passed its first external security audit.12
Operators
Serenita has run ethrex continuously for six months as one of five execution clients in its setup. RockLogic, a Lido curated node operator, runs it in production. Stakely added ethrex on July 8, 2026, after testing on the Hoodi testnet with more than 15,000 genesis validators.1
Audit
Least Authority audited ethrex between January and May 2026. The review found 20 issues and 8 suggestions. The final report, delivered on May 4, confirms all issues were addressed. Both reports are published in the ethrex repository.2
Releases
ethrex has shipped 13 major releases in 2026, on a weekly cadence since May. They run from v9.0.0, which introduced snap sync and made RocksDB the default, to v21.0.0, which adds Hegota fork support. A full mainnet sync takes about 1.5 hours on a machine with 4 to 8 cores, 32 GB of RAM, and a 1 TB NVMe disk. On Ethproofs, mainnet blocks are proven using ethrex’s EVM as the guest program, on ZisK since December 2025 and on Airbender since April 2026.1