I haven’t benchmarked this, but I have recently benchmarked Spark Streaming vs self-rolled Go vs Bento vs RisingWave (which is also in Rust) and RW matched/exceeded self-rolled, and absolutely demolished Bento and Spark. Not even in the same ballpark.

Highly recommend checking RisingWave out if you have real time streaming transformation use cases. It’s open source too.

The benchmark was some high throughput low latency JSON transformations.