EthSystems has released rotortree, an open-source Merkle tree library designed for privacy-focused applications and large commitment datasets used by shielded transaction systems on Ethereum. The group said rotortree rebuilt 90,435 historical commitments from Tornado Cash's largest 1 ETH pool in approximately 19 milliseconds, compared with about 8.58 seconds for the TypeScript library used in its benchmark, a reported difference of roughly 450 times. In a synthetic test, the durable configuration wrote 748 million commitments to disk in about 82 seconds. EthSystems attributed the results to parallel processing across CPU cores, a configurable tree with more than two children per node, and BLAKE3 hashing. Enabling durability through a write-ahead log reduced raw throughput by approximately 30% versus the non-durable configuration. The library does not address the continuing storage growth of long-lived privacy pools, and it has not undergone a formal security audit. EthSystems introduced rotortree on August 31, 2026, as the first release in its Building Blocks technical series. The project is available through crates.io and EthSystems' public repository under the MIT/Apache-2.0 licensing model. The reported performance will need independent testing, security review and adoption by privacy-focused application developers before its production significance can be assessed.