CacheCash

CacheCash is a high‑TPS private transfer minigame built on Hyli.

Play CacheCash now!

Overview

CacheCash showcases private, high-speed payments powered by proofs on Hyli.

Key features

• 🕶️ Private balances & transfers powered by zero-knowledge proofs
• ⚡ Instant local interactions with onchain finality
• 🧱 Composes Noir for privacy, SP1 for speed
• 💧 Fully private faucet: claim and spend without revealing balances
• 🎲 Simple, fast, and fully private gameplay
• 🔒 All data stays on your device

Links

• 🎮 Play the game
• 📘 Read the deep dive
• 🧰 Learn about Hyli

How to run

Prerequisites:

• Node.js ≥ 18
• Rust ≥ 1.75
• Noir
• Running Hyli devnet

Local development

1. Start the Hyli devnet locally (or point to a remote devnet) so the node RPC is reachable at http://127.0.0.1:4321 and the DA reader at 127.0.0.1:4141.

2. (Optional) Copy the default server configuration if you want to tweak ports or node URLs:

   cp server/src/conf_defaults.toml config.toml

   You can also override individual keys at runtime with environment variables such as CACHECASH__NODE_URL=http://devnet-host:4321.

3. Run the CacheCash server from the repository root:

   cargo run --release --manifest-path server/Cargo.toml

   The first boot generates and caches the SP1 proving key under data/hyli_utxo_state_pk.bin, so expect an extra minute the very first time.

4. In a second terminal, install frontend dependencies (uses Bun to stay in sync with bun.lockb) and start the Vite dev server:

   cd front
   bun install
   bun run dev

   If you prefer npm, run npm install followed by npm run dev; the values in front/.env control which endpoints the UI talks to.

5. Open http://localhost:5173 in your browser and start playing.

Docker

• Backend:

  docker build -f Dockerfile.server -t cachecash-server .
  docker run --network host cachecash-server

  Supply a custom config.toml via a bind mount (e.g. -v $(pwd)/config.toml:/app/config.toml) or environment variables if the devnet is not on localhost.

• Frontend:

  docker build -f Dockerfile.ui -t cachecash-ui .
  docker run -p 5173:80 cachecash-ui

  Set VITE_* variables with -e flags when you need the UI to target non-default endpoints.

Inspired by

• Payy
• ZCash