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🎲 Roll Dice

Simple dice rolling application using Ephemeral Rollups to demonstrate using MagicBlock's verifiable random function (VRF) to generate random numbers.

VRF Flow

The dice account is delegated to the Ephemeral Rollup. On the ER, the program requests randomness from the VRF oracle with a client seed; the oracle fulfills the request by invoking the program's callback instruction (e.g. CallbackRollDiceSimple) with verified random bytes, which become the dice roll.

Demo

https://roll-dice-demo.vercel.app/

Software Packages

This program has utilized the following software packages.

Software	Version	Installation Guide
Solana	3.1.9	Install Solana
Rust	1.89.0	Install Rust
Anchor	1.0.2	Install Anchor
Node	24.10.0	Install Node

agave-install init 3.1.9
rustup install 1.89.0
avm use 1.0.2

Build and Test

Install dependencies and build the program:

yarn
yarn build

This example runs against a local MagicBlock cluster — a base Solana validator, an Ephemeral Rollup fronted by the Query Filtering Service, and a VRF oracle that fulfills randomness requests. Start it in one terminal and leave it running:

yarn setup

yarn setup runs SETUP_ONLY=1 ./scripts/test-locally.sh roll-dice from the repo root: it builds this example, boots the validators and VRF oracle, and holds them until you press a key.

Then, in a second terminal, run this example's tests against that cluster:

yarn test:local

test:local sources scripts/local-env.sh so the SDK targets the local cluster (without it the tests fall back to devnet).

Tip: to build and run every example end-to-end (what CI does), run the repo-root ./scripts/test-locally.sh directly.

🚀 Launch the Frontend

To start the frontend application locally:

cd app

Install dependencies:

yarn install

Start the development server:

yarn dev

The application will be available at http://localhost:3000 (or another port if 3000 is already in use). The delegated dice demo will be available at http://localhost:3000/delegated.