Zachtronics' develops some of the most unique games in the industry. Their titles are genuinely hard to compare to anything else.

In EXAPUNKS, you solve programming puzzles that do an excellent job of teaching low-level concepts like registers and instruction sets. The core mechanic revolves around writing assembly-style code, but the real twist is parallel programming. You control multiple EXAs running simultaneously, with the ability to replicate EXAs, kill EXAs, and transmit data between EXAs. Each problem has an infinite number of solutions, and going back and optimizing them is a game on it's own. Fewer instructions, less cycles, fewest number of EXAs.

Story-wise, the game captures the nostalgia of early 2000s hacker culture extremely well. Each scenario feels distinct, with different objectives and constraints that keep things fresh. It never really gets boring, just intimidating when you first see a new task. But the satisfaction of having a solution is hard to compare.

As for difficulty, it ramps up quickly. I would recommend starting with SHENZHEN I/O, then moving on to EXAPUNKS, before finally tackling the wall that is TIS-100.