Vibecode build plans · № 3

Build a waitlist page

One sentence, one form, one honest test of whether anyone wants the thing.

A waitlist page is not a collection box — it's the cheapest experiment you can run on a pitch. One sentence about what you're building, one email field, and the market's answer arrives as a number. Which means the page has exactly one job: make the sentence land. Everything else on it is either supporting that sentence or diluting it.

One decision has to be made honestly up front: a static page can't store emails, and you should not build a backend for a waitlist. Pick a form service below (or a tiny Cloudflare Worker if you insist on owning it) and the prompts write themselves around your choice.

The spec — and the cuts

• Above the fold: promise, proof, ask. What it is in one sentence, one line of evidence you're real, one email field. A visitor who reads nothing else must still get it.
• One file, under 50KB, instant load — a waitlist link gets clicked from social feeds on phones, where slow means gone.
• Honest by default. Say what you'll send and how often ("one email at launch, maybe two before"). No invented counters, no fake scarcity — see the traps.
• Cut: analytics scripts, chat widgets, cookie banners you don't need, and the second section explaining features of a product that doesn't exist yet.

The prompts

Pick your form backend and options — the prompts rewrite themselves — then paste into your agent in order.

Where agents go wrong on this build

• Manufactured urgency. "Only 17 spots left!" on a waitlist is slop, and your smartest visitors — the ones you want — smell it instantly. If you have real numbers, show real numbers; if you don't, show nothing.
• Explaining a product that doesn't exist. Agents pad the page with feature grids and screenshots of vapor. Every section after the fold is a chance to talk someone out of the one action the page asks for.
• Validation theater. Twenty lines of regex to "validate" emails. type=email required is the entire correct answer; the form service does the rest.
• Forgetting the unfurl. A waitlist link lives in tweets, DMs, and group chats — it's seen as a preview card far more than as a page. Missing OG tags silently halve the click-through.
• Databases. If your agent starts writing a schema for a one-field form, stop it. That's what the form service is for.

Why the feedback step is in the plan

The pitch sentence is the one thing on this page you cannot judge yourself — it reads as obvious to you because you've been living inside the idea. And signups from friends won't tell you either: people who like you lie. What a reviewer can give you honestly is comprehension — what they think the product is, where their eyes stopped, which word made them tune out. Prompt 4 wires your agent to our MCP server so two or three people can pin exactly that on the live page before the internet sees it.