Fitnit · built in public

Lab

Working boards for design and product experiments. Each is built from real screenshots and real data rather than mockups, and re-generated as the app changes, so the record stays honest rather than becoming a highlight reel.

◎ Built in public. Real screenshots, real funnel numbers, and the reasoning behind each change — including the parts that went wrong. Published because the decisions are more useful than the conclusions, and most product writing only shows the conclusions.

Boards

Onboarding, every frame

Every screen of the signup flow, a scrubber for stepping through how it has changed across versions, and the PostHog funnel showing where it actually loses people.

v1.119.0 13 frames funnel data

Landing b-roll

Replacing the three carousel icons with photoreal plates generated on fal.ai, with the app's own UI composited onto the phone in each shot. Style rounds and comp tests.

3 slides fal.ai $1.65 spent

Next experiment

Drop a self-contained HTML export in scripts/lab/, run externalize.py, and add a card here.

empty slot

Served from src/public/lab/ · Cloudflare Pages, deploys on push
Add a board: python3 scripts/lab/externalize.py <export>.html --out src/public/lab --name <slug>
Images are content-hashed into lab/assets/, so a re-export only rewrites what changed.