Local Dev Environment

Knight Shield uses Docker Compose to run a complete local Midnight Network stack for development.

Docker Compose Services

The docker-compose.yml at the project root defines three services:

midnight-node

image: midnightnetwork/midnight-node:v0.21.0
ports:
  - "9944:9944"

Local Midnight node exposing WebSocket RPC on port 9944. This is the blockchain node that processes transactions and maintains state.

indexer

image: midnightnetwork/indexer:v4.0.0-rc.4
ports:
  - "8088:8088"

Block indexer that provides queryable APIs for transaction history, contract state, and balance lookups. The wallet SDK queries this for sync operations.

proof-server

image: midnightnetwork/proof-server:v7.0.0
ports:
  - "6300:6300"

ZK proof generation server. Required for submitting transactions that involve Compact contract calls — the proof server generates the zero-knowledge proofs that validate state transitions.

Starting the Stack

# Start all services in background
docker compose up -d

# Check status
docker compose ps

# View logs
docker compose logs -f midnight-node

# Stop all services
docker compose down

Network Configuration

When running locally, use the standalone network configuration in the core SDK:

import { NETWORKS } from '@knight-shield/core';

const config = NETWORKS.standalone;
// {
//   node: 'http://127.0.0.1:9944',
//   indexer: 'http://127.0.0.1:8088/api/v1/graphql',
//   proofServer: 'http://127.0.0.1:6300'
// }

Relay Server

The relay server runs separately from the Docker stack. It connects to the local Midnight node as its upstream:

# Default upstream: ws://127.0.0.1:9944
cd packages/relay-server
MIDNIGHT_NODE=ws://127.0.0.1:9944 PORT=8443 node dist/server.js

Environment variables:

• PORT — Server port (default: 8443)
• MIDNIGHT_NODE — Upstream Midnight node WebSocket URL (default: ws://127.0.0.1:9944)

Compact Compiler

Install the Compact compiler (compactc) from the Midnight Network developer tools:

# Verify installation
compactc --version
# Expected: 0.29.0

Compile contracts:

pnpm compile:contracts
# Outputs to build/ directory:
# - JS bindings (managed and witnesses)
# - ZK proving keys
# - ZKIR (zero-knowledge intermediate representation)

Mobile Development

iOS

Requires Xcode with iOS Simulator. Install CocoaPods dependencies:

cd packages/mobile/ios
pod install
cd ..
npx react-native run-ios

Android

Requires Android Studio with an emulator or connected device:

cd packages/mobile
npx react-native run-android

Metro Bundler

The Metro bundler serves the JavaScript bundle to the mobile app:

cd packages/mobile
npx react-native start

Troubleshooting

Issue	Solution
Node not syncing	Check docker compose logs midnight-node for errors
Proof server timeout	ZK proof generation is CPU-intensive — ensure adequate resources
Indexer not responding	The indexer needs the node to be fully synced first
Relay connection refused	Ensure the relay server is running and pointing to the correct node