Is it worth worrying too much about the security of the site if all monetary transactions are performed on the side (bank page, paypal, etc.)?

Question

Payment systems

Good afternoon/evening everyone.
There is an idea to create a medium-sized crowdfunding site with a narrow theme.
For this, it is initially supposed to be done on open CMS (special for crowdfunding or, for example, Drupal).
The site does not plan to store payers' data, and all operations will take place on the side of, for example, the bank.
Actually, the question is, is it possible, based on this, to spend a lot on a self-written engine and do everything on open CMS?
Thanks in advance for your replies.

Answer 1

It is possible if the cost of the work of a professional programmer/team is higher than reputational and other risks in case of any problems.
Perhaps my judgment is biased (I am a programmer and stamping sites on open source CMS does not attract me and takes away my clients due to price dumping), but a serious project on open source CMS is initially a "minus to the reputation" of the project.
Your own system is, of course, more costly to create a project, but with a good programmer (team), this system is more reliably protected (especially if the programmer has a "light paranoia" for security), an additional obstacle for attackers is the closed system architecture (black box) , often the speed of work is higher (due to the lack of costs for unused parts of the system and sharpening for specific tasks, instead of generalized algorithms), it is cheaper to maintain and develop the system in the right direction.
Naturally, all of the above implies professional performers. People who live within their profession. The above does not apply to a non-professional team / performer.
Moving away from bias, you can build a reliable and fast project on open systems, but often this product will still need to be finalized for the project and it will only come out cheaper if you find a professional specializing in this particular engine.
They are 2 sides of the same coin with many variables on both sides. The choice must be made on the basis of planning and risk assessment (both legal and financial), but not out of a desire to save.