E-commerce Site Development

I'm looking for an experienced website developer to create an e-commerce site where I can sell services.

Key Requirements:
- User-friendly interface
- Secure payment gateway integration
- Mobile-responsive design
- SEO optimization

Ideal Skills and Experience:
- Proven track record in developing e-commerce sites, preferably on Shopify, WooCommerce, or Magento.
- Strong knowledge of payment systems and security protocols.
- Experience in SEO and responsive design.

Please provide a portfolio with your bids.