Begin at the upload boundary
The upload service should accept large files without forcing one application server to hold the entire video in memory. A common design issues resumable upload URLs and writes chunks directly into durable object storage.
Once the source object is complete, an event starts the asynchronous processing pipeline. The user can leave while the platform transcodes, validates, and publishes the video.
Transcode for many devices
Workers turn the source into several resolutions, codecs, and bitrate segments. The work is naturally parallel, but every output must remain tied to one immutable source version so retries cannot mix incompatible artifacts.
- A queue absorbs spikes in upload traffic.
- Idempotent jobs make retries safe.
- A manifest records which renditions are ready.
- Failed renditions can be repaired without repeating every successful job.
Deliver through the edge
Playback begins with metadata and a manifest, then fetches small media segments through a CDN. Popular segments stay near viewers while the origin retains the durable copy.
The client continuously chooses a bitrate using recent bandwidth and buffer health. Good playback therefore depends on the storage, CDN, manifest, and player working as one feedback system.