Does CI suit for market place website dealing with ton of users and contents?

[eluser]Unknown[/eluser]
I am considering CI to be applied in my marketplace project. Basically, the site I am developing has requirements:
1. Handle tons of clients and contents (products)
2. E-commerce website automation
3. E-commerce features like cart, mailing system, forums, etc.

There are concerns such as speed, security, and future patches. Or, if I am missing something please advice.

Moreover, could you recommend 3rd party libraries I should be using while development for better productivity and quality?

One more thing, because a marketplace site is gonna be dealing with tons of pages. Could you recommend tools, libraries I should be using to deal with pages? Like SiteMesh, Smarty, etc.

Thank you,

[eluser]rogierb[/eluser]
I don't see how your requirements have anything to do with CI

<i>1. Handle tons of clients and contents (products)</i>
This is mostly Database and webserver related.
If you program poorly in any language, speed will suck. The same applies to CI and PHP

<i>2. E-commerce website automation</i>
<i>3. E-commerce features like cart, mailing system, forums, etc.</i>
Again programming, CI is fast if you program PHP correctly.

<i>There are concerns such as speed, security, and future patches. Or, if I am missing something pleaseadvice.</i>
Any website has those concerns. A very small part of those concerns will be CI.
CI can be as secure and fast as you want it to be. It depends all how well you program.

CI is 'just' a framework that allows you do develop quickly. Out of the box it is very fast and has some nice basic security features.

There are a lot of beautiful libraries out there. On tip I can give for a 'larger' site, go with modules (HMVC). It will make your live much easier.