[hampfi]

Not sure where you are working but not a lot of people work at/on a huge code base.

Most codebases are build and operated by 1-3 teams and if you are not able to reproduce your prod env as a test env, your architecture is broken.

[sagichmal]

The size of the codebase is orthogonal to the size/complexity of the production environment.

Modern architectures look like this: https://github.com/donnemartin/system-design-primer

It is generally not feasible to recreate all of the elements of this design in a totally separate testing environment.

[hampfi]

I know this very well and i'm stlil not seeing an issue.

We have 2 GCP accounts. One for production and one for test. Same Setup, not an issue due to terraform and the cost is reasonable for a test env.

[sagichmal]

Same network rules and configuration? Same CDN settings? Same DNS? Same data in the databases? Same volume of traffic on the queues?

(Rhetorical questions. Of course the answer is no.)

All of these things have huge impact on the actual similarity of the systems, and consequently how they behave.

[hampfi]

Obviously but this is not a black and white thing.

If it wouldn't make sense for us to have test and prod, we wouldn't do it but i can't imagine a scenario where this is NOT beneficial.