OSWALD (Object Storage Write-Ahead Log Device) is a Write-Ahead Log (WAL) design built exclusively on object storage primitives. It works with any object storage service that provides read-after-write consistency and compare-and-swap operations, including AWS S3, Google Cloud Storage, and Azure Blob Storage.

The design supports checkpointing and garbage collection, making it suitable for State Machine Replication (SMR).

See nvartolomei.com/oswald for more details.