How EF Core Migration Warnings Can Mislead in Modular .NET Applications

In modular .NET applications, EF Core's command-line migration tooling may only load a subset of the assemblies available at runtime, causing it to build an incomplete model. When a higher-level module contributes entity configurations that the tooling process cannot see, the differ may flag an existing table as missing and propose dropping it — a destructive operation that would damage a shared schema. This makes certain migration warnings technically accurate about the partial model the tool sees, yet dangerously incorrect from the full application's perspective. Rather than dismissing such warnings broadly or regenerating snapshots to silence them, developers should precisely document the loading boundary and narrow the exception to only the known false positive. The lost safety signal should be replaced with an executable migration guard that explicitly checks committed migrations for destructive operations — such as table drops or column removals — targeting the protected table.