Roast my prediction app — I think I’m building Polymarket for normal people. Tell me where I’m wrong.

[u/Charles_Crickmore]

Stacked — a social prediction app where you bet on anything with your mates using virtual coins. Tinder-style swipe to predict, 1v1 challenges with counter-offer negotiation, leagues with pick’ems, daily auto-generated bets, leaderboards. No real money.
Built it solo for 6 months.

The thesis I’m betting on:

Prediction markets have exploded — Polymarket, Kalshi, Manifold. They’re great, but 95% of people will never touch them. They’re built for traders. The markets are about politics and macro. Real money creates friction. Predicting against strangers feels like trading, not playing.

The missing layer is predictions between people you actually know, on things you actually care about. Will Tom break 90 this round? Will my brother actually finish his thesis this month? Same prediction-market mechanics, completely different stakes — reputation and bragging rights instead of P&L.

What’s actually built:
Full product, not a prototype. Full auth, dispute system with auto-resolver and admin queue, league system with kicks/atomic refunds/pick’em rounds, friend system, 1v1 challenge negotiation flow, daily house bets generated via Polymarket API. US legal pages, age-gated signup, abuse layer, and email infrastructure all shipped this month.

The real test:
Took it on a golf trip last weekend with my brother and 6 mates. All 7 signed up. 0 placed a single bet. Cold-start problem is real even when you bring the cold start with you on a plane.

What I think might be wrong (you tell me which one is actually it):
• Thesis is right but the activation flow is broken — first-bet friction is too high
• Thesis is half-right — friends will play, but only with something more at stake than bragging rights
• Thesis is wrong — without real money the motivation just isn’t there at the casual level
• I’m building Polymarket for normies but normies don’t actually want Polymarket in any form

Stack: vanilla JS on Netlify, Firebase Cloud Functions, Firestore.

Would love this group to tell me where the thesis cracks. Link in my bio if you want to check it out in real

[u/Rns70]

I loving gambling and I genuinely like this idea. So many times I have said to my friends "lets bet on X" as a joke. Would love for there to be a app where I could actually stake the money

[u/Charles_Crickmore → u/Rns70]

Really appreciate this — exactly the signal I’m trying to read. The “let’s bet on X” moment with mates is the whole reason Stacked exists.

On real money: there’s actually a path for that already built in. The app tracks every bet and keeps the running ledger in virtual coins, and you can settle up offline however you want — Venmo, cash, beers, whatever. Same way mates settle after a poker night. The app stays on the right side of the regulatory line (solo dev can’t clear sportsbook licensing), but the social ledger between you and your friends is real.

Curious — does that change it for you? Or were you imagining the app handling the actual money transfer itself?

[u/Hobophobic_Hipster → u/Charles_Crickmore]

Thanks, Claude

[u/Charles_Crickmore → u/Hobophobic_Hipster]

I Prefer Charles, but Claude works too

[u/stonks_lover]

2 quick challenges: 

• same challenge as kalshi and polymarket: definition of a win. What counts as a “finished thesis”? If there isn’t a clear definition for each bet, it won’t work. 
• would it make or break friendships? 🤣

[u/Charles_Crickmore → u/stonks_lover]

Both fair challenges, especially the first one — I’ve spent a lot of time on this.

Resolution model has a few layers: the bet creator marks the result by default, the other party can dispute within a window, and disputes escalate to adjudication if needed (currently me as admin, longer term voting within a league). For sports bets specifically, we auto-resolve via external API. So “Will Arsenal win tonight?” is automatic. “Will Tom quit his job this year?” relies on the creator + dispute system.

Not perfect — Kalshi has the same headaches with ambiguous markets — but for friend groups, social pressure does most of the heavy lifting. Nobody’s disputing a friendly bet too aggressively when the stakes are five beers.

On friendships: only breaks if someone refuses to settle up — at which point you’ve learned something useful about that friend anyway hahaha

[u/Charles_Crickmore]

Getting ahead of the obvious question — why not real money?

Two reasons.

One, regulatory. Real money makes it a sportsbook: state-by-state licensing, KYC, AML, 1099 tax reporting, responsible gambling compliance. Multi-million-dollar legal bar a solo dev cannot clear.

Two, and more interesting — real money collapses the product surface. You can’t legally take a real-money bet on “will Tom break 90 this round” or “will my brother actually finish his thesis this month.” Those markets only exist with virtual currency. Real money pins you to regulated event markets — the lane Polymarket and Kalshi already own.
The product is closer to a group chat with structure than a sportsbook. Reputation and bragging rights are the actual stakes between mates — real money usually makes it weird, not better. Manifold proved play-money prediction markets work.
If virtual stakes aren’t enough motivation, that’s the thesis being wrong — which is exactly the roast I’m here for.