PROC — the program underneath

Raised when the program lemonfiber shells out to is absent or will not run.

Code	Severity	Exit	What it means	What to do
PROC-1	error	3	The program lemonfiber drives the engine through is not installed, so nothing can be started or stopped.	Install Docker Desktop, or Docker Engine on Linux.
PROC-2	error	1	The program is installed and would not start. Usually a permission or daemon problem rather than a missing install.	Check the container engine is running, then try again.

What each severity and each exit means is on every error by code, beside every other family.