Custom E-commerce Site with Payment Integration

I'm looking for a skilled web developer to create a custom e-commerce website. The site should be responsive, high-performing, and tailored to my brand.

Key Requirements:
- E-commerce functionality with a shopping cart
- Payment gateway integration, specifically for credit card processing
- Secure, optimized for speed, and SEO-friendly

Ideal Skills and Experience:
- Proven experience in developing custom e-commerce websites
- Expertise in payment gateway integration, especially credit card processing
- Strong understanding of SEO and website optimization techniques
- Ability to create visually appealing and functional designs

Please provide examples of previous work and a timeline for project completion.