Pump on Gamblit

I built “Pump” for Gamblit, and honestly, it’s one of the most nerve-wracking games on the platform. It’s a classic crash-style betting game: you place your wager, and a multiplier starts climbing from 1.00x. The longer you wait, the more you win. But at any random millisecond, the pump explodes. Cash out before the crash, and you keep your multiplied bet. Get greedy and hold on a second too long? You lose everything.

The Vibe We Were Going For

1. Multiplayer Tension: Playing alone is boring. I wanted a live dashboard where you can see exactly when other players chicken out and cash their bets. It adds this massive layer of peer pressure.
2. Zero-Friction Gameplay: Cashing out needs to be a single, massive button. No confirmation dialogs, no lag. Just raw reaction time.
3. Visual Stress: The UI had to convey rising tension. As the multiplier goes higher, the visuals get more intense.

How It Works

1. The Live Multiplier:

   • It’s the heart of the game. Driven by WebSockets, it updates smoothly in real-time across every connected client simultaneously.

2. The Live Leaderboard:

   • You see exactly who is in the current round. As the multiplier climbs, you watch players drop out and secure their profits in real-time.

3. Auto-Cashout:

   • Don’t trust your own reflexes? You can set a hard limit (e.g., automatically cash me out at 2.50x) before the round even starts.

The Engineering Behind the Crash

• Frontend: Built with Svelte and SvelteKit. When a game relies on millisecond reaction times, you can’t have a bloated virtual DOM slowing things down. Svelte’s reactivity was perfect for this.
• Real-Time Backend: Node.js hooked up to Socket.IO. It handles broadcasting the multiplier ticks to thousands of active clients simultaneously.
• Game Logic: Pure TypeScript. Crucially, the crash point is generated using a provably fair cryptographic hash before the round even begins. The server knows when it will crash, but the players don’t.
• State Management: Redis handles the frantic pace of player bets and cashouts, keeping the main database from getting hammered during a round.

The Result

Pump quickly became the most chaotic, adrenaline-fueled game on the site. The chat goes crazy when someone holds on past a 50x multiplier, and it’s brought a massive social element to Gamblit.

“The adrenaline rush from Pump is unreal! There’s nothing like watching that multiplier climb past 10x, with your heart pounding as you debate whether to cash out or hold on for just a second longer. Seeing everyone else cash out early just adds to the pressure. It’s easily the most exciting game on the site.”