I built a tool that recreates the Bicep Heart trend from one photo - week one numbers inside
The Bicep Heart trend is a short-form video pose that went viral: two people standing back to back, flexing, hands forming a heart behind their heads. Every version has the same pose, the same rhythm, the same camera framing.
I kept seeing people ask how to make one without filming. Text-to-video tools can sort of do it, but every render invents new motion, so the output rarely looks like the trend. So I built Bicep Heart: you upload one photo, and it renders a 7-second vertical video of you doing the exact routine from a fixed reference clip.
How it works
- One JPEG/PNG/WEBP photo of a person, up to 10 MB
- Motion comes from a fixed reference clip via a motion-control video model (Kling through APIMart, roughly $0.40 per render), so pose, timing and camera framing stay identical across outputs
- Google sign-in, English and Chinese UI
- Credits are one-time packs that never expire; failed renders refund automatically
Stack
| Layer | Choice |
|---|---|
| Runtime | Cloudflare Workers + TanStack Start SSR |
| Data | D1 for orders/users/credits, R2 for uploads and renders |
| Async | Cloudflare Queues with a dead-letter queue and a 5-minute cron sweep |
| Payments | Dodo Payments as merchant of record, Standard Webhooks signatures |
The interesting engineering bit was credits. A render can fail silently upstream, so every job goes through a queue with a DLQ, and a cron job reconciles stuck jobs and refunds credits. Refund-on-failure was non-negotiable: nobody trusts a video generator that eats money on error 500.
Week one numbers (no launch, just SEO)
- Google Search Console, day 7: 414 impressions, 8 clicks, average position 8.2
- 34 pages indexed; per-locale canonical + hreflang, llms.txt, IndexNow submitted
- Most impressions come from what-is-the-bicep-heart-trend style queries - good for discovery, weak for conversion
What I am doing next
Distribution, not more code. The site works; nobody knows it exists. Next: short-video samples on social platforms, newsletter outreach, and watching which queries convert.
If you want to try it: bicepheart.site. Feedback welcome, especially on pricing (Starter $4.99 / 7 credits, one render is 7 credits).