Daily creating a Sitemap stored in the meteor app (as an asset not on the cloud)


I would like to create a cron jobs that would daily create an updated Sitemap for my site to adapt to the new entries in the database. I know where I am going with the function to create the Sitemap. However I would like the Sitemap to be stored directly in the app, as an asset, and not on the cloud or any external service. And I have to admit I have a hard time to grasp the concept of file storage within the Meteor app. Can I have a file that would be served directly in the app on my hosting service (more or less like any static image I would have in my public folder). And If yes how can I dynamically create, store and erase the file on a daily basis ? (Do I have to use FS ?)

Thanks in advance for your help.

P-S : I know about packages for creating dynamic Sitemap but they are not suitable for a large number of entries (over 100s) as they use too much ressources. Rather create a new one at night everyday.