[scarface74]

The most expensive parts of AWS for us are:

RDS - hosted non proprietary databases.

EC2 - Standard VM hosting

Redshift - a proprietary OLAP database that uses standard Postgres drivers

S3 - object storage. But there are so many S3 API compatible storage providers, there is little “lock-in”

But the fact is that lock-in is overrated. Your CTO is statistically as likely to move their entire infrastructure just because a few engineers promised it would be “seamless” as your DBA is going to move away from their Oracle installation because developers “used the Repository Pattern to abstract database access”.