Enough about us, let‘s talk more about you. The Software Engineer position might be a good fit if you:

Have production experience with several programming languages. We mostly use PHP and JavaScript at Automattic – you should either be familiar with them already or the idea of using them on a daily basis should not be a blocker for you.
Have experience working on a large-scale system. Making it faster, more scalable, and fault-tolerant.
Know about systems architecture.
Are highly collaborative and you love participating in code reviews and discussions about architecture, or design.
Are passionate about and experienced in software development; in particular, advanced PHP knowledge is a plus.
Are knowledgeable about design patterns and testability; having experience with testing frameworks, performance testing and unit testing is very welcome.
Are thoughtful about product design, with good user experience instincts.
Are open and able to travel 3-4 weeks per year to meet up with your teammates in person.