We believe the best research teams are built through context, taste and a real feel for where the field is headed next.
To me, being a senior engineer is not primarily a function of your ability to write code. It has far more to do with your ability to understand, maintain, explain, and manage a large body of software in production over time, as well as the ability to translate business needs into technical implementation.
The hottest new programming language is English.
While companies may put language about increasing expertise in their engineering levels, the real lens that they use to evaluate that expertise is through increasing scope of ownership, delivery, and impact. These more senior levels are not a measure of betterness, or quality, or raw intelligence and technical skills. They are instead a measure of demonstrated impact and confidence in the scope of work that the person can be tasked to accomplish.
Software teams want to hire people with aptitude, not a particular skill set. Any skill set that people can bring to the job will be technologically obsolete in a couple of years, anyway, so it’s better to hire people that are going to be able to learn any new technology rather than people who happen to know how to make JDBC talk to a MySQL database right this minute.