Vibe Coding in Xcode 26.3 Delivers a Sewing-Pattern App in Under 48 Hours

An independent developer uses Xcode 26.3 and Claude Agent to migrate a sewing-pattern project and rapidly add ML, OCR, and NFC features, producing a cross‑device iPhone/Mac/Watch app in under two days. After solving stability issues from background agents by enforcing strict update rules, the codebase grew to 32,381 lines across 116 files (52,947 added, 10,626 deleted). The experience showcases a huge productivity boost from AI-assisted coding, tempered by the fragility of agentic workflows and ongoing UI/UX considerations, with a possible App Store launch on the horizon.