(I was a codesmith resident in 2022, just as the covid hiring bubble started to burst, take that bias as you will)
You're entirely right. What Codesmith teaches isn't revolutionary. Lars touches on it in his blog, but there are really only three things that have contributed to the success they had, and none of them have anything to do with the technology or languages/frameworks they teach:
1. Build a very strong enrollment pipeline that filters for highly motivated individuals who are also technically capable of self-learning. There's a lot of (free) coursework in their CSX platform that needs to be completed prior to even enrolling in the main program as well as passing both a behavioral and technical interview to be accepted. This sets a higher technical floor so the program can start fast without the risk of losing students. Good candidates => good graduates.
2. Focus the program primarily on self-learning principles. "Hard learning" was always Codesmith's motto. Lessons were very high level in order to push students toward official documentation. Instructors/fellows/mentors all actively discouraged the use of tutorials which are a waste of time. Projects proposals are screened for uniqueness. You don't learn anything following step by step instructions for an app someone else built to solve a problem that isn't yours. Unique problems will require unique solutions which will require actual understanding of the technology.
3. Go really hard on on soft skills and leveraging past experiences. Be it technical or otherwise, nearly everyone had at least a few years of experience in "real" careers. Residents have already proven they can interview well enough to be hired at least by someone. Of my cohort of ~30-35 residents, I can only remember a couple that I didn't want to work with due to either their technical ability as the program ramped up or their coworking ability in general. A brief scroll through r/cscareerquestions or r/csmajor shows how abysmally low the bar is when it comes to soft skills in tech. Even if you ignore college students and only look at those that have been hired in industry, now that I can see it firsthand, the "average" Codesmith student is astonishingly above average in this regard.
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It's really not rocket science. When you start with a pool of people that are personable, technically capable of learning, career oriented, and mature, you're obviously going to get graduates that are able to punch way above their weight-class. Once you find 30-40 of those people, all Codesmith has to do is put them in the same room together for a few months, without the distractions of life and work, and just facilitate their own, collaborative self-learning.
This is in stark contrast with many bootcamps who will accept anyone that's willing to part with their money without any screening of ability. These I'd truly call snake oil praying on people's desire for a better life.