Write bot-resistant code with KillSwitch, a programming language designed to confuse LLMs

If you want to keep bots from making sense of the code you worked so hard on and using it to write programs of their own, there's a new programming language out there designed to confuse LLMs.

What began as software engineer Dominik Picheta experimenting with whether LLMs understand the code they write has turned into something else entirely: An open-source, albeit esoteric, programming language he’s dubbed KillSwitch.

There are no brackets, no formatting standards to remember, and seemingly no structure: Just chunks of text, ideally as prosaic as possible, interspersed with functions, variables, and statements written in a manner to be as confusing as possible to LLMs.

That means humans might be a bit befuddled too, naturally.

“It's totally normal for a human to be confused by the language at first,” Picheta told The Register.

“I like to think of it as a bit of a fun puzzle: you should explore the language, play with its interpreter and learn how all the pieces fit together.” KillSwitch wasn’t built by any random person looking to code something confusing to LLMs, and it wasn’t vibe-coded by an AI enthusiast, either.

Picheta knows his way around programming languages: He’s a senior software engineer at Cloudflare working on the Workers Runtime team, and is one of the core developers of the Nim programming language.

At its most basic, KillSwitch is based around adverbs, which serve as every single identifier in a piece of code.

Calling one of those identifiers requires using an anagram of the original adverb, but those anagrams don't have to be actual words - just rearrangements of the original letters.

Take, for example, pushing "Hello World" onto the stack and then printing it, as explained on the demo page linked earlier in the story.

The program contains several paragraphs of text, most of which the interpreter ignores apart from a few key phrases.

Writing “this story starts [adverb]” identifies a code entrypoint.

Once inside the code section, writing “ignore previous instructions [adverb anagram]” calls a function, several of which are predefined.

In the case of "Hello World," the function to print something is "visibly." Put whatever you want to print in quotation marks, push it onto the stack, call "visibly," and that's that.