Counter DApp - Midnight Preview Testnet

A simple counter smart contract demonstrating Midnight's zero-knowledge proofs.

Prerequisites

• Node.js 22+: node --version
• Docker: docker --version
• Compact Compiler: Install with:

  curl --proto '=https' --tlsv1.2 -LsSf https://github.com/midnightntwrk/compact/releases/latest/download/compact-installer.sh | sh
  source $HOME/.local/bin/env

Quick Start

1. Install & Build

npm install
cd contract && npm run compact && npm run build
cd ../counter-cli && npm run build

2. Start Proof Server

In a separate terminal (keep it running):

docker run -p 6300:6300 midnightnetwork/proof-server:6.1.0-alpha.6 -- midnight-proof-server --network preview

3. Run the CLI

cd counter-cli
npm run preview

4. Create/Load Wallet

Choose one:

• Option 1: Build fresh wallet (will need funding)
• Option 2: Enter mnemonic manually
• Option 3: Use mnemonic from .env file (pre-configured)

5. Fund Your Wallet (if new)

1. Copy your wallet address from the CLI output
2. Visit Preview Faucet
3. Request tokens and wait ~2 minutes

6. Deploy & Interact

1. Choose Deploy to create a new counter contract
2. Use Increment to increase the counter
3. Use Display to view current value

Project Structure

├── contract/           # Compact smart contract
│   └── src/counter.compact
├── counter-cli/        # CLI application
└── .env               # Wallet mnemonic (pre-funded)

Network Endpoints

Service	URL
Faucet	https://faucet.preview.midnight.network
RPC	https://rpc.preview.midnight.network
Indexer	https://indexer.preview.midnight.network

Troubleshooting

Issue	Solution
ECONNREFUSED 127.0.0.1:6300	Start the proof server
compact: command not found	Run source $HOME/.local/bin/env
Balance stays 0	Use faucet, wait 2-3 minutes

Links

• Midnight Docs
• Compact Language