Amazon S3 upload that actually works

Just read about another "surviving dropped connections" S3 upload design. Cool. We've all been there, waking up at 3am because a user's 2GB video file corrupted mid-transfer. The multipart upload retry logic is solid engineering, but let's be real: the real nightmare isn't the network. It's the cleanup. Everyone writes the happy path. Nobody writes the garbage collector for orphaned parts. That S3 lifecycle policy for incomplete multipart uploads? That's the unsung hero. I've seen buckets with 50GB of abandoned chunks because some dev thought "the client will always call CompleteMultipartUpload." Spoiler: clients crash, browsers close, tabs die. My hot take: if you're not logging the upload ID and tracking state in your own DB, you're flying blind. The article mentions "lost completions" but glosses over the real edge case: what happens when the client thinks it uploaded but your server never got the completion signal? You need a reconciliation job. Run it nightly. Trust me, your future self will thank you when you're not manually querying S3 at 2am. Also, please stop using presigned URLs for everything. Multipart uploads via presigned URLs are a security footgun. Use a proper upload service that manages the flow server-side. Your API gateway will thank you.