When major code hosting platforms go down, development grinds to a halt. A lightweight service could maintain read-only mirrors on alternative platforms, failing over automatically during outages.
Small engineering teams would pay for this business continuity protection, especially those deploying frequently.
Start by building GitHub-to-GitLab syncing for a single repo. Later add multi-directional sync and more providers.
Risk includes complexity of merge conflicts if both mirrors receive pushes during restoration.