CodeKeyboard Rebuild Notes

Written so a human or an LLM can rebuild the keyboard without inventing APIs. CodeKeyboard is a system Android keyboard (IME), not a text box demo — split Sofle-inspired layout, multiple layers, home-row modifiers, and on-device prediction that learns personal and mixed-script typing (Banglish included) without a server. These notes walk through the canvas rendering, composing/selection handling,…