How can we execute a rule/process model on login?

You could direct users to a "Welcome" page that doesn't let them perform any work and contains a single button.

When they press that button, they go to their real landing page.  You could use the "Welcome" for all sorts of things, like broadcasting announcements that you know everyone will get.  That may make up for the trade-off of needlessly adding at least another click to each User's day.  All the while secretly the whole point is to attach a DB write to that button, so you at least know every time someone logs in and goes to their start page.

It helps if you upgrade to 18.4 and gain the ability to turn Tempo off.  A pre-18.4 workaround I heard about is a plugin with a redirect script that kicks users back to their landing page site if they try to access Tempo URL.

That seems like a neat workaround, though maybe not all that feasible for an established / already-in-production system.

That seems like a neat workaround, though maybe not all that feasible for an established / already-in-production system.

My requirement is, no asynchronous job, no change is user experience. Inclusion on welcome page becomes a change in user experience.