Liftoff is an an excellent book. Recommended for anyone interested in SpaceX or space in general. The writer's style is a bit dry, however it's a fun story regardless. The gritty insides of the early days of SpaceX are both what you hoped to read about and sort of crazy remarkable (like the elaborated story about the imploded Falcon 1 that was being transported by C17 and ultimately saved SpaceX from oblivion). People risked their lives to make SpaceX happen.

It reminds me of a bigger company version of Masters of Doom. Same hacker ethos driving those early days.

>to go along with their lean/agile development process.

This is an accurate take, but in reality I think they convinced the government to outsource a lean/agile development process.

20+ years ago, NASA went through their "better, faster, cheaper" phase to try their own hand at a more agile environment. Unfortunately, it reduced quality and whenever something bad happened more requirements were levied. Now some are beneficial but there's also some that were bureaucratic and process bloat just because of political risk and the fact nobody wanted to be on record saying the risk was acceptable.

I think one unspoken risk is whether the government, as the largest SpaceX customer, will try to enforce the same quality and safety standards as the company matures, particularly with human-rated spaceflight. Or if they are comfortable with a hands-off approach.