[chickenpotpie]

Because it's significantly harder to isolate problems and you'll end up in this loop

* Deploy everything * It explodes * Rollback everything * Spend two weeks finding problem in one system and then fix it * Deploy everything * It explodes * Rollback everything * Spend two weeks finding a new problem that was created while you were fixing the last problem * Repeat ad nauseum

Migrating iteratively gives you a foundation to build upon with each component

[wizzwizz4]

So… create your shadow system piecewise? There is no reason to have "explode production" in your workflow, unless you are truly starved for resources.

[paulddraper]

Does this shadow system have usage?

Does it handle queries, trigger CI actions, run jobs?