Skip if workflow has already run

[sachatt]

Is there any method to skip triggering the workflow if it has already run ?

For example, I have a workflow which builds/compiles an app. I then have some other workflows (like nightly tests, weekend soaks, etc.) which will fetch/download the build and run some tests. However these items can also be executed independently, so we are unsure if a build is started/not run/etc. and want to avoid wasting time on a re-run.