Every interruption costs 23 minutes of deep focus (UC Irvine). Your editor saves files — not what you were thinking. Dev Checkpoint captures your mental context in 1 keystroke: git branch, active file, cursor position, open TODOs, terminal history. Restores with a human-readable narrative in 3 seconds. Zero cloud. Zero AI. Zero config. Everything stays on your machine. Free, open source MIT. Works immediately after install.