Just released Sigma Engine on GitHub, a Rust-based library with the focus on performant and scalable matching of Sigma rules against logs. It implements Sigma rule parsing, processing pipelines as known from pySigma and a multi-threaded matching engine. Currently, it's in a very early stage and not yet released on crates.io, APIs might change.

On top of this I plan to build a CLI for applying Sigma rules on EVTX or JSON files as well as a web API server for integration into log pipelines.