Can a prompt replace Canva?

Build a small canvas design editor using an open-source canvas library (Fabric.js or Konva) with a handful of size presets for common formats — a square social post, a portrait story size, a header banner, a printable page — plus a custom-size option. Support text using fonts already on the machine, image upload, basic shapes, a layer list with reordering, and simple alignment and snap guides. Load a small brand panel from a config file — a handful of brand colors and two fonts as one-click swatches — so a personal brand stays consistent across designs without redoing it each time. Save each design as a file that reopens exactly as it was; duplicating a saved design is the whole 'template' system, no separate template engine needed. Export to PNG at a couple of resolutions, and to PDF by rendering the canvas to a printable page. Keep everything local, with no accounts and no telemetry.

Do not build a stock-photo or template library, an AI image generator, or real-time collaboration — bring your own images, and treat this as a single-user tool. The licensed asset library and the ability for two people to edit the same file live are Canva's actual product, not a weekend of canvas code.