I can modify and integrate or upgrade Opencart perfectly with your existing website
i can make change in any script which is based on (php, Javascript, SQL)
you can give me challange i always work like a challange with problem and Thank GOD i always Success
if you want custom core solution we also can build it
i can make modifcation in any CMS, or frameworks because we have full grip in programming languages
if you want own cms we also can build it for you
you need to only come inbox
Kindly come in chat for further discussion on your work.