Incredible - even the maximum size of an environment variable is not set in stone.

And may now be overridden by the delegate, who may want to do that in case he forks the process through a shell.
Forking is something that might at some point be a standard feature of the base delegate actually ... .
cleaned up process launch mode handling significantly

Now the delegate is the only one to define how to launch a process. Now it's possible to spawn, replace, or fork
a process, and all of the modes have a real-work requirement and need.

Also the interface of the process controller is not cluttered anymore with a special need, and
launch_mode replaced the previous spawn flag.

In short, it's much better now, and allows to write cleaner delegates