I work in an org that has strong partitions between devs and sysads. Dev can make and test code. They have no access to prod. Sysads can configure and execute what devs make. They have read-only access to the source repos.

Problems with this are as follows (real, not imagined)

1. AWS cloudformation scripts - who makes them? If dev does, sysads can't change.

2. Does dev have the security mindset to maintain configurations in IaaS things like Cloudformation? Who reviews things like NACLs, Security Groups, VPCs, and the like?

3. Scripts - how big or what impact does a script need to be written by sysad or dev?

4. Oncall - normally are sysads job, but when you implement strong gates between dev/sysad, you need oncall devs.