A neat twist on chess tactic puzzles where you have to do a bit more visualization to solve the tactic.

They've also recently added pieceless tactics for even better blindfold practice: https://listudy.org/en/pieceless-tactics/1203

An open source (Javascript) Xiangqi engine with a puzzle solver (3,000 mate-in-n puzzles!)

This was helpful for starting a go project.

Control theory for line-following bots

This is a bit disconcerting... "The majority of calling state machines I investigated had logic vulnerabilities that allowed audio or video content to be transmitted from the callee to the caller without the callee’s consent. This is clearly an area that is often overlooked when securing WebRTC applications."

Some helpful advice for writing Go.

You can play any of the Commodore 64 games in the Internet Archive directly in your browser using their Vice-based emulator! The only annoying thing is that you have to configure a joystick in port 1 for most games before you start playing.

Ben Hoyt's great write up of an AWK interpreter he wrote in Go, including an overview of the lexer, parser, interpreter, unit tests, and profiling for performance improvements.

Calls itself "an open source pastebin with runnable snippets and API". It's a nice and useful REPL environment for many langauges. More simple than repl.it

"Thinking meat! You're asking me to believe in thinking meat!"