Every sufficiently large infrastructure organization eventually builds software whose purpose is coordinating other software.
That is a control plane.
The interesting question is not whether you will build one. It is whether you will build it intentionally.
Jenkins was often supposed to be CI. Then it became the place where deployments, approvals, secrets, scripts, and operational rituals accumulated.
ServiceNow was supposed to manage tickets. Then it became the de facto gate for production change.
Terraform began as infrastructure as code. Then state, policy, automation, and workflow accumulated around it.
Organizations repeatedly create control planes accidentally because coordination has to live somewhere.
A control plane is not merely automation. It encodes decisions about what is allowed, who can act, how change happens, and how failure is handled.
When those decisions are implicit, the control plane becomes fragile.
AI can propose more changes than humans can review manually.
That requires a structured layer where proposals become inspectable, comparable, reversible, and learnable.
Nexplane's thesis is that engineering organizations need a control plane for engineering judgment, not merely infrastructure execution.