Amazon S3

Use it when

• The platform runs on AWS; every engine and table format reads S3 natively, and colocated compute keeps in-region traffic free.
• Durability and compliance are table stakes: eleven nines across three or more availability zones, Object Lock to SEC 17a-4.
• Data has a lifecycle: eight storage classes from Express One Zone to Deep Archive, with Intelligent-Tiering moving objects for you.
• The bucket should participate in the platform: notifications to SNS, SQS, Lambda, or EventBridge, and S3 Tables for built-in table-format awareness.

Think twice when

• Data leaves AWS often; egress past the free 100 GB a month is the cost that makes multi-cloud and multi-engine designs expensive, and is R2's whole pitch.
• The estate is on-premises or air-gapped, where MinIO or Ceph provides the same API self-hosted.
• Cold-tier data churns: the colder classes carry 30-, 90-, and 180-day minimum durations with early-deletion charges.

How it runs

Nothing to operate: a fully managed regional service with versioning, lifecycle policies, and IAM- and policy-based access control down to prefix level. Cross-region replication is opt-in, with a 15-minute RTC option. S3 on Outposts extends the API on-premises. It is the reference implementation the entire S3-compatible ecosystem measures itself against.