WordPress plugin development for gravity forms custom extension plugin

Our US based web development agency is looking for experienced and reliable web developers to work with us on a long-term basis (full-time or part-time). We have a small defined WordPress plugin development project as a test to find the right people. Are you experienced in WordPress plugin development, API development, and web speed optimization for wordpress and shopify? Please include your related experience to these three areas and include git repos or link to projects. Small custom plugin development job to find a developer we can work with long-term for our company. Create a custom plugin that will be an extension to Gravity Forms. The plugin will collect the subtotal of all product fields in any gravity forms, add a calculation of processing fees (3% + $0.30) and then add a checkbox field for visitors to have the option to add the cost of processing fees to their order. When checked a calculated product will be added to their total. It should be created as a plugin with a new custom gravity form field that can be added to any form. Have a settings menu with configurable settings sitewide for the processing fee, and settings on the form field itself to: - Select which product fields to calculate for the transaction fee - Choose language for the checkbox to accept the transaction fee - The language in the checkbox should also include the live amount of the calculated rate We currently have this functionality by adding some custom fields, jQuery and gravity form extension plugins to to add the "cover our processing fees" checkbox feature on payment forms. We want this turned into a plugin that can be easily configured for a non-technical person. See form feature to cover processing fees here that we have already built: [login to view URL] and a similar plugin here: [login to view URL] this one will be an addon for gravity forms