Every cabinet here was built by a kid. Yours takes about an afternoon.

What you get before you start

The starter is a working, empty game. Sign-in that needs no email and no password, so a player can play in the first second. A save in the database with a wall between one player and the next. A game loop that runs at a steady speed instead of racing on a fast phone. Emails rewritten so they read like a message from a person. And a screen that says "this game broke, that is worth reporting" instead of going white.

Two things it deliberately leaves empty, because they are the game and they are yours: the rules file, and the page where you say what your game gets wrong. That second one is not optional. A game that scores you and never admits what it left out does not go on this wall.

The house rules

Paste these into your project as the second thing you do. They are what stops the AI wandering off and what keeps your players safe.

• No real names. Not yours, not anyone's — a handle is how people know you here.
• No chat, and no box where one player writes something another player reads.
• The save lives in the database, one row per player, walled off from every other player.
• Never trust a number the browser sends. Work out the score on the server.
• Never rank players against each other by score, money or speed.
• Say what your game gets wrong. An AI wrote it and it left something out — name it, in your words.
• If a fix fails twice, stop and find the cause. The third try is where projects die.

The ten prompts you skipped

The starter already did these. They are here so you can see what was done for you — and so you can run them yourself if you would rather start from nothing. Paste them in order. Prompt 1 goes in Plan mode; the rest in Build mode.

Five ways it will fight you

It keeps not working

Stop at three attempts and revert to your last good version. A fourth try usually breaks something that was fine.

Login worked in preview, broke when you published

Your published URL is missing from the project's redirect URLs. Add it before you publish, not after.

The preview looks broken

Reload it twice before you believe it. The preview lies more often than the code does.

Your credits vanished

You asked for five things in one prompt. Ask for one thing, look, then ask for the next.

You reverted and your data is gone

Reverting restores your code, not your database. Those are two different things.

If you are a teacher

This runs as a unit without much from you. A class builds one small game each, publishes it, and then reviews each other's — which is where the actual learning sits, because reviewing someone's game means checking their numbers against the real world. A student needs no email and no password to play, and the account they build with can be anonymous.

What it teaches

Unit economics from measurable parts — material, machine time, failure rate, fees, postage — and the difference between a number a system reports and a number that is true. Students state a prediction with a confidence before they check, which is the habit the whole thing is built to install.

Ages

Eight upwards, in the same room. The first lock needs no research and no reading age; the second needs sourcing; the third needs a record of your own wrong answers.

What we do not do

No real names, anywhere — the database refuses a handle that matches a student's name. No chat and no direct messages. No ranking of students by score, money or speed. No streaks, no notifications, no points for turning up.

What a lesson looks like

One period to build, one to publish and review someone else's, and a standing fifteen minutes a week on the open lock. Everything is browsable in any order — there is no day one and nothing is ever late.

If you want to run this with a class and something is in your way, say so through Feedback anywhere in the arcade. The parts that schools need and we have not built yet are worth knowing about.

Where the credits come from

Building on Lovable costs money, so it is fair to ask who pays and what they get out of it. An adult pays for the account this arcade runs on. Nobody here earns anything when you click a link on this page — there is no referral link on it, on purpose, because a page that teaches you to spot hidden incentives has no business running one. If that ever changes, it will be written here first, in plain words, before it is true.