I took a quick glance at the code, I believe it may build upon "Build Your Own Database From Scratch in Go" [0]. The first part of the book is available for free on the author's website, along with information on how to purchase the full book (which includes source code).

I share the same goal and am working through the material after working through Codecrafters' "Build your own SQLite" [1]. Good luck!

I apologize in advance for mistakes (formatting, et cetera). I just registered this account to point you toward resources I found helpful.

[0] https://build-your-own.org/database/

[1] https://app.codecrafters.io/courses/sqlite/overview

Does something like this exist for java, don't want to take the burden of a new language.

I don't think these things really fit the bill, but this is closest I could find. All the codecrafters stuff is focused on reading from a sqlite DB. A great start, but you're not implementing B+ trees.

Hope this gives you some options.

https://github.com/Arminas42/build_your_own_database

https://github.com/search?q=codecrafters+sqlite-java+languag...

it's not that hard, you should try it :)