ecFlow is a client/server workflow package that enables users to run a large
number of programs (with dependencies on each other and on time) in a controlled
environment. It provides reasonable tolerance for hardware and software
failures, combined with restart capabilities. It is used at ECMWF to run all our
operational suites across a range of platforms.

ecFlow submits tasks (jobs) and receives acknowledgments from the tasks when
they change status and when they send events, using child commands embedded in
your scripts. ecFlow stores the relationships between tasks, and is able to
submit tasks dependant on triggers, such as when a given task changes its
status, for example when it finishes.