This one? I only looked for a moment, but filebeat appears to be ingestion only. Benthos does input, output, side-effects, stream-stream joins, metrics-on-the-side, tiny-json-wrangling-webooks, and more. I find it to be like plumbers putty, closing over tooling gaps and smoothing rough edges where ordinarily you'd have to write 20 lines of stream processing code and 300 lines of error handling, reporting, and performance hacks.