TL;DR A migration bundle packages every pending migration for one DbContext into a single, runtime-targeted executable. No source code or dotnet-ef tool needed on the target machine. They exist to get schema changes out of your running application and into a single, deliberate, auditable step, ...
Source: [Dev.to](https://dev.to/johnntirintis/ef-core-migration-bundles-what-they-are-why-they-matter-3896)