Media & streaming · Beginner

Podcast hosting

Episode upload and processing, RSS feeds behind a CDN, and IAB-style download counting.

Every part, and why it is there

Podcasters

Upload episodes, write show notes, schedule releases and watch download stats in a web dashboard.

Load balancer

Spreads dashboard and upload traffic. Small compared with listener traffic, which never comes this way.

Creator API

Manages shows and episodes and hands out pre-signed upload URLs so large audio files go straight to storage instead of through the API.

Shows & episodes

Show metadata, episode titles, publish dates and audio file references: everything needed to build a feed.

Episode audio

Original uploads plus the processed MP3/AAC files that are actually published. A popular show can serve petabytes a month from here via the CDN.

Processing jobs

Each new upload triggers a job, so creators are not kept waiting while audio is processed.

Audio processing

Normalises loudness, encodes to standard formats, writes ID3 tags and chapters. Done once per episode, not per listener.

Podcast apps & listeners

Apple Podcasts, Spotify and many smaller apps poll every subscribed feed regularly and download new episodes, often automatically overnight.

CDN (feeds + audio)

Caches RSS feeds for a few minutes and audio files indefinitely. Feed polling from millions of apps would otherwise hammer the feed generator.

RSS feed generator

Renders each show as an RSS 2.0 file with enclosure links. RSS is the whole distribution API: publish it once and every app can pick it up.

Download redirect

Enclosure URLs point here first: it logs the request and immediately redirects to the CDN. That log line is the only signal a host gets, because apps do not report plays.

Download logs

Raw request records (IP, user agent, byte range, time) waiting to be cleaned into downloads.

Download counting

Filters bots, merges the many partial range requests one listener makes, and de-duplicates the same listener within 24 hours, following IAB measurement guidelines that advertisers trust.

Download stats

Downloads per episode per day by app and country, for the dashboard and for ad sales.

Learn more

All system design examples