How do you keep one value identical across five repos?

We had five repos and the same source value living in five places. Every pipeline was green — because each repo was right by its own local standards. Change a value and the basis written next to it in one pull request, and every guard in that repo stays green.

Nothing in the code was broken. The denominator was.

I've spent the last two months building a verifier around one rule: a check that didn't run is not a check that passed. It answers pass, violation, or unjudged, and never folds the three into a percentage — the folded number hides exactly the cells where this class of bug lives.

Two things I'd like to hear from people who have lived this.

1. 1. How do you keep a shared value identical across repos today? Hand-copy plus code review? A published package? A generator? I want to know what actually survived contact, not what the docs said you'd do.

2. The cross-repository check has a constraint I'm not happy about. The canon and the copy have to be readable in the same CI job — our entrance clones the peers for you, but it is still one job holding both. Where does that break for your setup? Separate orgs, a private canon, a canon nobody is allowed to clone?

We launch tomorrow. I'd rather fix the model than defend it.