How to restrict access to source codes for developers?

Question

Information Security

We are going to work with the widest assortment of developers, how to give them tasks so that they do not have access to the secret places of the system? If you try microservices, then you still need to make an API from the main server, so you need access. Or is it not possible at all?

Answer 1

Or is it not possible at all?

Maybe. The dependence is simple and clear: the less the developer knows about the product being developed, the worse the result of his work. For a better understanding of the problem, read somewhere how a coder differs from a programmer.

Answer 2

The core and glue between the joints of separately encoded modules.
As glue - a system of interfaces controlled by the kernel.
All this is designed by the architect of the software complex.
Requirements and regulations for creating modules - written by technical writers according to the requirements of the architect.

Answer 3

If you keep it secret, they will just hide it out of principle.
In general, everything is simple: the system is divided into modules, the modules are documented, only their developers have access to the source codes of the modules.