Show HN: Flowchart AI – Write English, get a flowchart

Hi HN,

I’m an indie developer who kept running into the same bottleneck during code reviews and product planning: Someone would describe a process—“A → B if success else C”—and I’d stop everything to sketch it out. So I built a tool to turn plain English into editable flowcharts.

### What it does

- You can describe a process in natural language, and get a fully editable flowchart rendered on the page. - No login required for a one-time free run. - Logging in with Google (via BetterAuth) gives you one diagram per day. - It uses Gemini 2.5 Flash under the hood. - For now, exporting is only supported in `.excalidraw` format—but SVG/PDF are coming soon.

### Tech stack

- Frontend: Next.js 15 + TypeScript + Excalidraw - Backend: Vercel Serverless Functions - Auth: BetterAuth - Database: Supabase - Storage: Cloudflare R2 Bucket (S3-compatible)

### Try it

- Live demo: https://flowchartai.org The hosted version has usage limits due to server and model costs.

- Source code (MIT-licensed): https://github.com/tanchaowen84/flowchartai If you prefer, you're welcome to self-host the open-source version instead.

### Why I’m sharing

I built this to solve a personal pain point. Would love to hear if it’s useful to you, or if there’s something obviously wrong I missed. Bug reports, suggestions, architecture critiques — all welcome. I’ll be in the comments all day.

Thanks for taking a look.