GNU Pies (pronounced "p-yes") stands for the Program Invocation and
Execution Supervisor.  This utility starts and controls execution of
external programs, called "components".  Each component is a stand-alone
program, designed to be executed in the foreground.  Upon startup pies
reads the list of components from its configuration file, starts them,
and remains in the background, controlling their execution.  When a
component terminates, pies tries to restarts it.  Its configuration
allows to specify actions other than simple restart, depending on the
exit code of the component.

GNU Pies supports a wide variety of component types and gives the user
complete control over the execution environment of each component.  This
includes modifying shell environment, running components with the given
user privileges, etc.  The standard error and/or output of any component
may be redirected either to a disk file or to syslog.

WWW: https://puszcza.gnu.org.ua/projects/pies