Web, email and seo expert

I am looking for someone who can design and code websites, using both existing cms solutions such as wordpress, magento etc and coded data driven sites. The person would also need to understand SEO, PPC and social media, as well as be able to construct HTML emails, understanding the limitations of email browsers, yet still creating glossy designs.

The person would need to understand the latest web and social media technologies and be able to work effectively within these areas.

The role would include working on sites for customers as well as developing and promoting our own in house online presence. For the right person I would consider a monthly retainer/ongoing employment.