Nethermind

On August 19, 2026 Nethermind announced that it had joined the Chainlink network as a node operator and strategic technology provider. As a node operator it helps secure the Cross-Chain Interoperability Protocol, CCIP, which moves tokens and messages between blockchains, and the Data Feeds that publish prices onchain. As a technology provider it offers tooling, infrastructure operation and integration services to teams that build on Chainlink. Daniel Celeda, then chief executive of Nethermind, said at the announcement that being a node operator carries real responsibility for the reliability of a network.

With the move, Nethermind gave up its role as a verifier in the Decentralized Verifier Network of LayerZero, where The Block counted it among the largest third-party verifiers. Nethermind cited an extensive review and named no specific technical problem. The Block placed the change in a series of moves from LayerZero to Chainlink after the attack on the rsETH bridge of Kelp DAO in April 2026, which drained 116,500 rsETH, then worth about 292 million dollars.

Since the Merge, every Ethereum node runs two programs: a consensus client that follows proof of stake and an execution client that executes transactions and holds the state. The Nethermind client is an execution client built on .NET, first released in 2019 after a grant from the Ethereum Foundation in 2018. Nethermind puts the share of nodes that run its client at around 30 percent.

Nethermind built the client to add diversity among Ethereum clients, because a bug in a client that most nodes run would hit most of the network at once. For node operators the company also publishes Sedge, an open-source tool that installs a full proof-of-stake node with its execution and consensus client.

The security team of Nethermind has carried out more than 400 smart contract audits of contracts, protocols and infrastructure, including audits of zero-knowledge circuits. With formal verification it proves mathematically that code behaves as its specification says. Since 2025 the team has also used AuditAgent, an AI tool that reviews code inside the audit process, and it publishes its public audit reports online.

On June 23, 2026 UBS and Nethermind reported two completed proofs of concept for compliance controls on Ethereum. In the first, an Ethereum node applied rules such as limiting transactions to pre-approved addresses, and in the second, a component sent bundles of approved transactions through relays to selected block builders. Both tests ran on the Sepolia test network without live transactions and without changes to the Ethereum protocol.

Alvin Su became chief executive of Nethermind in September 2026, after he had been its chief business officer, and he earlier worked as head of quantitative technology at BNP Paribas Asset Management. Daniel Celeda, who led the company at the time of the Chainlink announcement, is now chief technology officer. Tomasz Stańczak founded Nethermind in 2017 and wrote most of its Ethereum execution client.