This is bare bones project that includes Confluent's all-in-one docker compose and basic Scala Main class that can be used to test your Kafka Streams application locally.
Start kafka
docker compose up
Once it is running view the confluent control center at http://localhost:9021/
You will want to create a topic called test-topic
with 100 partitions or whatever you choose to test.
Run the scala app in a new terminal.
sbt run