November 2024
S3 now have the append functionality to append data to existing object.
s3.put_object(Bucket='amzn-s3-demo-bucket--use2-az2--x-s3', Key='2024-11-05-sdk-test', Body=b'123456789', WriteOffsetBytes=9)
More examples here -
https://docs.aws.amazon.com/AmazonS3/latest/userguide/directory-buckets-objects-append.html#directory-bucket-append