Developer to integrate Mailchimp and Shopify

We have recently migrated to Salesforce and I need some help developing our system. We have the main integration between our website and Salesforce set up and basic Mailchimp integration but this needs development. We also need to set up integration with a Shopify store we have which is separate to our website. I'm looking for someone with plenty of experience in these areas who will be able to recommend best practice as well as setting them up. I have estimated duration as this is flexible. We may have ongoing work for the right person. I'm not sure which languages are required for this so please ignore 'required skills'.