Consensys has released Teku 26.8.0, the latest version of its open-source Ethereum consensus client, as a recommended update containing bug fixes and breaking changes. Teku combines a full beacon node with validator-client functionality for Ethereum proof-of-stake infrastructure. The August release makes several operational changes that node operators should review before upgrading production systems.
Version 26.8.0 continues Teku’s requirement for Java 25 or later, a dependency first made mandatory in version 26.6.0. Consensys documentation warns that earlier Java versions are no longer supported. The Java requirement is therefore not new to 26.8.0, but remains a prerequisite for operators moving onto the latest release.
Legacy Eth1 Deposit Handling Is Removed
The most consequential breaking change removes Teku’s legacy web3j-based mechanism for retrieving validator deposit logs. Nodes no longer require an Eth1 JSON-RPC endpoint for that purpose, and the associated --eth1-endpoints, --eth1-endpoint and deposit-contract request-size command-line options have been removed. Validator deposits are now sourced through Ethereum’s newer in-protocol deposit architecture instead of Teku independently polling historical Eth1 logs.
That transition builds on EIP-6110, which moved validator deposit information into execution-layer blocks so consensus clients can process it directly. Ethereum’s specification says the design removes the previous consensus-layer deposit voting mechanism and reduces dependence on JSON-RPC polling. Teku 26.8.0 is effectively retiring client-side infrastructure that became unnecessary after Ethereum standardized deposit processing inside the protocol.
Teku also removed two non-production validator-tool commands previously used to submit deposits, while its generate-keys functionality remains available. The deprecated GetDepositSnapshot RPC endpoint has also been removed. These changes primarily affect operators and tooling that still depend on legacy interfaces rather than introducing a new Ethereum consensus rule.
Archive Node Operators Face a Known Issue
The release includes two documented bug fixes. Teku now prevents Beacon REST API sockets from being retained indefinitely when clients cancel pending asynchronous requests by introducing a 30-second timeout. It also fixes an edge case where BeaconBlocksByRange could return an empty response when requesting a single block. Both fixes target client behavior and API reliability rather than changing validator economics or Ethereum’s consensus parameters.
Consensys has nevertheless identified a known issue affecting archive nodes that still use a leveldb-tree database. Those nodes may experience extremely long startup times after installing 26.8.0, and the release notes advise affected operators to consider avoiding this version. That warning makes database configuration an important pre-upgrade check despite the release being generally recommended.
Teku 26.8.0 is available through Docker Hub and as signed tar.gz and zip binary distributions with published SHA-256 hashes. For Ethereum infrastructure teams, the update is primarily an operational modernization release, removing obsolete deposit-processing paths while tightening API behavior and maintaining the Java 25 runtime baseline.