What went through my head when I read the job ad.
"Are you self-motivated? Do you strive to be the best? Do you want to be an integral part of our explosive growth?"
- Yes, yes, but I don't like explosive things.
"you'll have to be super smart, well-versed in CS concepts and studies""
- They are probably going to ask me to implement sorting algorithms on a board, from their website their product seems simple, no need to back to my old algorithms book, who knows.
"Both founders (Andy and Jessica) studied computer science before starting the company, and they wrote most of the initial code until product launch."
- Ok, I will be dealing with a lot technical debt.
"...you will communicate across our accounting and sales teams to discover what will make our clients super happy and what will help us increase sales in new verticals..."
- I'm sorry, this is not what a lead engineer does. No serious engineer would want to do that, I would be busy enough dealing with technical debt, implementing new features and actually leading a team of engineers.
"Looking to the long-term, you will also need to upgrade Rails, make sure our servers will scale, ensure high-security, and modularize key parts of the code base. We know that even if you're leading a team you'll probably still want to spend time coding, so this role also affords the time to do hands-on programming."
- See, you want more than one person. And you clearly don't really understand the role of a lead engineer. You are asking for a CTO/Product designer/Engineer.
This is why I didn't even consider applying.