Laravel / PHP / Javascript development

I run a flipbook creation platform that converts PDFs to online flipbooks that needs to be updated to allow for:

Subscription enablement with Stripe (already using Stripe for payments, just not on a subscription basis)
Mobile responsive flipbook viewing
Added functionality in the flipbook process (ability to insert forms)
Upgrading to the current versions of Laravel and other libraries in use.
Solving a bug with reduced visual quality on some larger PDF conversions.

Future upgrades include:
Ability to use custom subdomains / domains with LetsEncrypt
Mobile

This is a system living on a VPS with a few different mysql databases for different environments, sending mail through sendgrid.

You should have:

Very strong PHP programming
Very strong Laravel programming
Strong JavaScript ideally, any framework is okay - it's mostly using jquery right now, so vue, react, etc., are all fine. This will likely be required for improving the mobile support.

Please send a message with details of your relevant experience for this position, and your preferred approach and framework for testing, whether unit testing or otherwise.