WordPress Site Update with E-commerce

I need an experienced WordPress developer to update my existing site by adding e-commerce functionality.

Key Tasks:
- Integrate a secure and user-friendly e-commerce platform
- Ensure mobile responsiveness and SEO optimization
- Maintain the site's current design aesthetics

Ideal Skills and Experience:
- Strong background in WordPress development
- Proven experience with e-commerce integration
- Knowledge of SEO and responsive design principles
- Familiarity with security protocols to protect user data

Please provide a portfolio showcasing similar projects.