AWS launched S3 Files, an EFS-backed feature that mounts any S3 bucket or prefix as an NFS filesystem on EC2, containers, or Lambda, with changes batched back to S3 roughly every 60 seconds.
Rather than collapsing file and object semantics into a single model (an early design attempt called "EFS3" that the team abandoned after deciding it produced only the lowest common denominator), Andy Warfield describes a "stage and commit" architecture borrowed from version control: EFS holds the live filesystem view, S3 stays the source of truth on conflict, and key names that can't be represented in both worlds emit events instead of failing.
