It looks good but it's from 2023 (postgres 14). Does anyone have anything from after 2025?

I think this is the most up to date.

https://www.interdb.jp/pg/

Different author but also very interesting.

They keep publishing Russian version of this book, with the latest covering PostgreSQL 18: https://edu.postgrespro.ru/postgresql_internals-18.pdf

AI should do a decent job translating it to English.

On an unrelated note, this reminds me of the excellent books published by Mir Publications. Russian books in general are of very high quality.

To your point, PG15 has a pretty meaningful change to its base backup protocol

https://github.com/wal-g/wal-g/issues/1385

Awesome.