Php developer to develop custom add-ons to an existing script

I am searching for an experienced php developer to develop custom add-on to an existing script which is called : atozseo tools. demo of the script can be seen here :
https://codecanyon.net/item/atoz-seo-tools-search-engine-optimization-tools/

The script use :
 Private framework built with pure php. Design pattern is MVC and contains router method, separate template section, multilingual support etc.
 The add-ons of the script are installed by admin in the back-end, where you have to import a file with the following ending :”.addonpk”
I want to develop 5 add-on for the script . they are not complicated , but you have to understand the script and then tell me if you can do it ?
 These add-ons should follow the same structure of add-on in script
 These add-ons should follow coding standards.
 These add-ons should be secure
 These add-ons should use minimum resources in the front end
 No design needed to be add and bootstrap should be used if needed. Add-on Page structure will be provided.

I will explain these add-ons in private

Please not that the script is licensed and it install per server. If needed a ftp access to the licensed domain could be provided .

If you read my project to the end and would like to apply , please write at the beginning of your bidding reply the word :”kaposta”. Every bid with out will be ignored .
preferred bids for freelancers with knowledge and experience with the script
Thanks