Minimal AI coding agent (~950 LoC Python) inspired by Claude Code. Works with any LLM. Think NanoGPT for coding agent. Formerly NanoCoder.

CoreCoder

Formerly NanoCoder — renamed to avoid confusion with Nano-Collective/nanocoder. All links from the old repo redirect here automatically.

中文 | English | Claude Code Architecture Deep Dive (7 articles)

512,000 lines of TypeScript → ~950 lines of Python.

I spent two days reverse-engineering the leaked Claude Code source — all half a million lines. Then I stripped it down to the load-bearing walls and rebuilt them in Python. The result: every key architectural pattern from Claude Code, in a codebase you can read in one sitting.

CoreCoder is not another AI coding tool. It's a blueprint — the nanoGPT of coding agents. Read it, fork it, build your own.

$ corecoder -m kimi-k2.5

You > read main.py and fix the broken import

  > read_file(file_path='main.py')
  > edit_file(file_path='main.py', ...)

--- a/main.py
+++ b/main.py
@@ -1 +1 @@
-from utils import halper
+from utils import helper

Fixed: halper → helper.

What You Get

Claude Code's 512K lines distilled into ~1,400 lines across 7 patterns that actually matter: