I can think of three things that you'll really really really want to be on top of while scaling up
1. your architecture must allow for vertical scaling. this means upgrading your hardware to beefier, stronger, faster machines with more CPU power and more memory. vertical scaling is often a very cost effective of improving performance.
2. your architecture must allow for horizontal scaling. this means being able to provision and deploy new instances of your application servers very easily, using an automated process. more servers running in parallel is a very effective way of handling increased load.
3. you must be able to monitor and protect your systems. https everywhere. highly secure passwords everywhere, and you should rotate your passwords on a regular basis. log everything and set up services to monitor your logs and notify you when weird/bad shit happens.
1. your architecture must allow for vertical scaling. this means upgrading your hardware to beefier, stronger, faster machines with more CPU power and more memory. vertical scaling is often a very cost effective of improving performance.
2. your architecture must allow for horizontal scaling. this means being able to provision and deploy new instances of your application servers very easily, using an automated process. more servers running in parallel is a very effective way of handling increased load.
3. you must be able to monitor and protect your systems. https everywhere. highly secure passwords everywhere, and you should rotate your passwords on a regular basis. log everything and set up services to monitor your logs and notify you when weird/bad shit happens.