I have considered writing a book about this stuff but it's an insanely bad use of my time vs. building tech in this space from a profit perspective. Defi is the highest possible way that a software engineer can earn money in 2021 without being some high-up FAANG architect or hit the startup lotto. Small teams are making millions or tens of millions of dollars, and they are making actual value (not ICO scams like in 2017!) with billions of dollars flowing through it.

If you want to break into this space, start with the bitcoin white paper, read this book[0], then do the Ethereum white / yellow papers, start messing around with smart contracts, then consume every possible piece of knowledge you can, because it's all spread out everywhere without good central repositories of knowledge.

Defi is protocolized finance. It's making building blocks of financial tools that people and projects fit together in new ways to accomplish various things (earn interest, hedge, go leveraged long, buy insurance, etc. etc. etc.). The possibilities are truly endless and the space is open for innovation like never before as there are no rules and regulations, and there never will be any! Good luck!

[0] https://www.amazon.com/Mastering-Bitcoin-Programming-Open-Bl...

You will get 10 different contradictory answers because the whole ecosystem is a mess. It's filled with huge amounts of technical complexity, opaqueness, bad actors, and so many gotchas and snafus you didn't forsee that you will be wondering where all the money went. It has no viability and you would be best to stay as far away from it as you can.

Read this and the papers mentioned inside it to get an overview of the market:

https://messari.io/pdf/messari-report-crypto-theses-for-2021...

It might be worth it to get a pro subscription at messari.io or theblockcrypto.com for a saner alternative to crypto twitter and other news outlets.

The quickest way to learn is to actually use it. Make trades on uniswap, earn fees with a liquidity pool, get some sushis, stake them, etc. etc. Unfortunately these days eth gas fees are very expensive though and you will spend a lot of money in fees.

It's nice to read about the history how everything involved and get to know some of the characters behind. Two books i enjoyed: - Bitcoin Billionaires - from the guy who wrote that book from the facebook movie - Out of Ether, how Ethereum got started

It would take quite a bit time, but with enough dedication, it's not that difficult. The books: Mastering Bitcoin and Mastering Ethereum (although ethereum one is a bit outdated now) cover a lot of it pretty nicely and you can find them for free on github.