+ (operating-system-essential-services os))))
+
+(define (operating-system-with-gc-roots os roots)
+ "Return a variant of OS where ROOTS are registered as GC roots."
+ (operating-system
+ (inherit os)
+
+ ;; We use this procedure for the installation OS, which already defines GC
+ ;; roots. Add ROOTS to those.
+ (services (cons (simple-service 'extra-root
+ gc-root-service-type roots)
+ (operating-system-user-services os)))))
+
+(define* (operating-system-with-provenance os #:optional config-file)
+ "Return a variant of OS that stores its own provenance information,
+including CONFIG-FILE, if available. This is achieved by adding an instance
+of PROVENANCE-SERVICE-TYPE to its services."
+ (operating-system
+ (inherit os)
+ (services (cons (service provenance-service-type config-file)
+ (operating-system-user-services os)))))