if you already know the library you're using inside and out and have built such a thing before, maybe you could whip it out in a couple hours This is the key,

if you already know the library you're using inside and out and have built such a thing before, maybe you could whip it out in a couple hours This is the key, I think. I was in the same boat as OP not so long ago in thinking that I was unreasonably slow. I'm not; I'm just a generalist. People who specialize in one specific area of technology can bang out something in their wheelhouse in a few hours because that's all they do, all day, every day. It makes them seem like superheroes. If you're working on a team with all specialists, it can make you look even slower by comparison. As for what to do about it, I'm stuck between either finding a specialty, going into management, selling my own software products (ie: work for myself) or finding a way of communicating my work in a way that makes me look like a superhero too.