What hard scifi books could you recommend?

Hello! Could you please recommend some hard science fiction books? I am struggling to find a good one. My favorites are Blindsight and Echopraxia by Peter Watts, but I have failed to find anything similar.

I also enjoyed The Martian by Andy Weir and The Murderbot Diaries by Martha Wells, though in my opinion, these aren't quite what I would call hard science fiction.

Additionally, I enjoyed books that blend fiction and non-fiction, like Harry Potter and the Methods of Rationality by Eliezer Yudkowsky and Gödel, Escher, Bach by Douglas Hofstadter.

What are your favorite hard science fiction books?