The first paragraph mentions he's going to use radare2 to reverse some shellcode and provides links to the official website and a comprehensive guidebook. You can lead a horse to water...

FYI, the link to the official site in the article is broken; it should be: http://www.radare.org/

A brief introduction usually prefaced with something along the lines of "In case you're not familiar with ..." or something like that is always appreciated!

(Also, since the author is asking for feedback [even though not specifically regarding this issue] I believe OP's comment is even more appropriate and helpful.)

Hey, I'm the author of the post (just found out someone linked it here). I've fixed the link to radare2.org now.. Can't believe I hadn't noticed that to be honest.

When I get home from work tonight I will add a short intro to r2, cheers for the feedback.

I felt the same -- it lacked skimmable context. But according to the intro to the linked Radare2 Book [1]:

It's a set of cli tools for reverse engineering and analyzing binaries. Includes a scriptable hex editor, a disassembler, a binary diff tool, and a hasher/integrity checker.

[1] https://www.gitbook.com/book/radare/radare2book/details

I'm the author of the post, I'll look at adding a short into to r2 when I get home from work tonight. Thanks for the feedback :). I (wrongly) assumed that anyone reading the article would be aware of r2.