Overview
Updates require more than a large download. Clients need matching manifests, patches and full installers, with verifiable provenance and integrity.
This is an architectural planning example, not a customer case study, a delivered project or a promise of performance gains.
Separate manifests from installers
Use immutable version paths for installers and timely freshness policies for manifests. Overwriting an old path does not make every client immediately receive the new file; include version identifiers in the release process.
Use a reversible release sequence
Publish and validate files before changing the manifest. Retain the previous version for rollback. Checksums and software signing belong to the release process; a CDN does not replace them.
Validate large-file transfers
Test range requests, resumed downloads and timeouts, and observe origin load during peaks. Keep each path's content stable so resumed transfers cannot mix different versions.
Test with the actual updater
Cover full and incremental packages, upgrades from older versions and recovery. Verify manifests, sizes, checksums and signatures, and check cache handling when withdrawing a faulty release.