Just like warpstream or confluent freight cluster, but AutoMQ is source available, you may find the key s3 wal implementation here: https://github.com/AutoMQ/automq/blob/main/s3stream/src/main...

AutoMQ claims this is the best design for streaming storage on the cloud: Shared WAL + Shared Object. This new shared storage architecture for streaming systems can leverage the advantages of different cloud storage services. They use only a few lines of code to implement features like building a Kafka service on S3. This blog shows how they achieve this. What do you think?