Cronos VS Quartz

HangfireIO/Cronos: Fully-featured .NET library for working with Cron expressions. Built with time zones in mind and intuitively handles daylight saving time transitions (github.com)

We do this sort of thing with an IHostedService in our application that uses a cron expression (using https://github.com/HangfireIO/Cronos) to control when to process the task

You could use this: https://github.com/HangfireIO/Cronos

In java we have found Quartz( Quartz) , Job Runr(Jobrunr) and db-scheduler(db-scheduler) and need to evaluate these for our use case.

Im mit sit what you mean by "not supported", you sure can run MongoDB on Kubernetes. Maybe I'm way off, are you saying that you can't use Quartz (this one: http://www.quartz-scheduler.org/ ?) because it doesn't natively allow you to load from MongoDB and.therefor you can't use it?

Uh this class is even worse, SDF is not a thread safe date formatter, so it never should be `final static`. `releaseDate` and `new Date()` will be ignorant of summer/winter time changes. For such scheduling one should use Quartz https://www.quartz-scheduler.org/

Have a look at http://www.quartz-scheduler.org/ If you're using Java

Long time I used http://www.quartz-scheduler.org which worked nicely, I wonder why Scala does not seem to have something standard for this.

Quartz Scheduler

We have a separate service for running cron jobs. It uses Quartz (http://www.quartz-scheduler.org/) and it has a REST API that we use to submit new jobs. It's easy to set up and all you need is a database. You definitely need a database in order to synchronize across different containers.