We did the migration off ASP.NET a couple years ago. Our site wasnt that big, but we had some major anti-patterns that we decided to address during the migratio

We did the migration off ASP.NET a couple years ago. Our site wasnt that big, but we had some major anti-patterns that we decided to address during the migration. (we had multiple CSPROJs for "Businsess Logic" and "Data Access Layer" that didnt do anything of value, end effect was simpler code an ~70% less LOC) There were a few major design changes that we had to embrace in the migration, mainly the middleware and DI. But we still managed to greatly increase performance, reduce our code footprint and get inline with the future Microsoft's vision for a C# webserver. All in it probably took 2 out of the 10 devs a month to complete the migration, while also addressing critical bugs.