Original Reddit post

One of the Claude experiments I’ve really enjoyed is the guided learning of how to build a programming language: Xo (pronounced ex-oh). I set up an AI lead (which I monitored and summarized all the work as it was progressing) and then had 3-5 worker agents build out the spec and then the prototype in Go. Once it was at a mature enough place, it started converting the core code like compiler, runtime, TLS library, tests, etc. over to Xo. It was exciting to see it come alive piece by piece. In the past, it would have taken a lot of trial, error, and frustration to see the process. With AI, we can enjoy the ride, help make key decisions, and learn how to build so many of the things we dreamed about. Instead of using sub agents, I set up persistent agents (just open terminal tabs to Claude code) and then had the lead agent task and communicate out all of tasks to the worker. I told the lead to compact the worker agents after tasks to help limit long session context. This worked well to help curb the context spend that sub-agents would have generated. The process, every code commit (redacted of sensitive information), blog articles along the way, and the current state of the language is available in the link. A few more stats on the project in the first 17 days: 3.9 million lines of code written. 1.8 million lines of code deleted. 57 billion tokens across Claude Opus and DeekSeek AI agents. Total cost: $400 in subscriptions (2 x Claude Max 20x with $35 in DeekSeek) The total cost of this project if I was not on AI subscriptions, but direct API billing is between $15K and $17K. Happy to answer questions. submitted by /u/motojo

Originally posted by u/motojo on r/ClaudeCode