┌─────────────────────────────────────────────────────────────────┐
│                    Local Development Stack                       │
├─────────────────────────────────────────────────────────────────┤
│                                                                  │
│  ┌─────────────────┐  ┌─────────────────┐  ┌─────────────────┐ │
│  │  Midnight Node  │  │    Indexer      │  │  Proof Server   │ │
│  │                 │  │                 │  │                 │ │
│  │  ws://127.0.0.1 │  │ http://127.0.0.1│  │ http://127.0.0.1│ │
│  │     :9944       │  │     :8088       │  │     :6300       │ │
│  │                 │  │                 │  │                 │ │
│  │  - Blockchain   │  │  - Query state  │  │  - ZK proofs    │ │
│  │  - Consensus    │  │  - Index txs    │  │  - Verification │ │
│  │  - State        │  │  - GraphQL API  │  │  - Circuits     │ │
│  └────────┬────────┘  └────────┬────────┘  └────────┬────────┘ │
│           │                    │                    │           │
│           └────────────────────┼────────────────────┘           │
│                                │                                 │
│                    ┌───────────┴───────────┐                    │
│                    │   Your dApp / Tests   │                    │
│                    └───────────────────────┘                    │
│                                                                  │
└─────────────────────────────────────────────────────────────────┘

When to Use

Setting up local Midnight development environment
Running node, indexer, and proof server locally
Troubleshooting infrastructure issues
Syncing component versions
Building/testing without testnet

Official Repositories

Component	Repository	Purpose
Dev Tools	midnight-infra-dev-tools	Scripts & guides for local setup
Node	midnight-node	Blockchain node (Substrate-based)
Indexer	midnight-indexer	State indexing & GraphQL API
Ledger	midnight-ledger	Proof server & ZK circuits

Quick Start

Step 1: Clone Dev Tools

git clone https://github.com/midnightntwrk/midnight-infra-dev-tools.git
cd midnight-infra-dev-tools

Step 2: Select Commit Version

The dev tools allow you to select specific commits for each component to ensure compatibility.

# Check available versions
cat versions.json

# Or select specific commits in the config

Step 3: Clone Component Repositories

# Clone the node
git clone https://github.com/midnightntwrk/midnight-node.git

# Clone the indexer
git clone https://github.com/midnightntwrk/midnight-indexer.git

# Clone the ledger (proof server)
git clone https://github.com/midnightntwrk/midnight-ledger.git

Step 4: Start Infrastructure

# Start all three components
./scripts/start-all.sh

# Or start individually:
./scripts/start-node.sh
./scripts/start-indexer.sh
./scripts/start-proof-server.sh

Component Details

Midnight Node

The blockchain node handles consensus, state management, and transaction processing.

Default Endpoint: ws://127.0.0.1:9944

# Start node
cd midnight-node
cargo build --release
./target/release/midnight-node --dev

# Or use Docker
docker run -p 9944:9944 midnightntwrk/midnight-node:latest --dev

Key Features:

Substrate-based blockchain
Block production
Transaction pool
State storage

Midnight Indexer

Indexes blockchain state and provides GraphQL API for queries.

Default Endpoint: http://127.0.0.1:8088

# Start indexer
cd midnight-indexer
npm install
npm run start

# GraphQL playground available at:
# http://127.0.0.1:8088/graphql

Key Features:

Real-time state indexing
GraphQL API
Contract state queries
Transaction history

IMPORTANT: The indexer must be synced with the node version. Update the metadata that the indexer interprets when changing node commits.

Proof Server (Ledger)

Generates and verifies zero-knowledge proofs for transactions.

Default Endpoint: http://127.0.0.1:6300

# Start proof server
cd midnight-ledger
cargo build --release
./target/release/proof-server

# Or use Docker
docker run -p 6300:6300 midnightntwrk/proof-server:latest

CRITICAL: The proof server must use the same ledger version integrated into midnight-node. Check version in:

midnight-node/Cargo.toml lines 63-70

Example from Cargo.toml:

[dependencies]
midnight-ledger = { git = "https://github.com/midnightntwrk/midnight-ledger", rev = "abc123" }

Version Synchronization

Why Version Matching Matters

All three components must be version-compatible:

Node produces blocks with specific ledger format
Indexer parses blocks using matching metadata
Proof server generates proofs for the ledger version

Checking Versions

# Check node's ledger dependency
grep "midnight-ledger" midnight-node/Cargo.toml

# Check indexer metadata version
cat midnight-indexer/metadata/version.json

# Verify proof server version
./proof-server --version

Syncing Indexer to Node

When you change the node commit:

Find the ledger version in node's Cargo.toml
Update indexer metadata to match
Restart indexer to re-index

# Update indexer metadata
cd midnight-indexer
./scripts/update-metadata.sh <node-commit>
npm run reindex

Configuration

Network Configuration

Create a config file for your dApp:

// config.ts
export const localConfig = {
  node: {
    url: "ws://127.0.0.1:9944",
  },
  indexer: {
    url: "http://127.0.0.1:8088",
    graphql: "http://127.0.0.1:8088/graphql",
  },
  proofServer: {
    url: "http://127.0.0.1:6300",
  },
};

export const previewConfig = {
  node: {
    url: "wss://rpc.preview.midnight.network",
  },
  indexer: {
    url: "https://indexer.preview.midnight.network",
    graphql: "https://indexer.preview.midnight.network/graphql",
  },
  proofServer: {
    url: "https://proof.preview.midnight.network",
  },
};

Environment Variables

# .env.local
MIDNIGHT_NODE_URL=ws://127.0.0.1:9944
MIDNIGHT_INDEXER_URL=http://127.0.0.1:8088
MIDNIGHT_PROOF_SERVER_URL=http://127.0.0.1:6300

Using with Starter Template

The starter template integrates with local infrastructure:

# Clone starter template
git clone https://github.com/MeshJS/midnight-starter-template.git
cd midnight-starter-template

# Install dependencies
npm install

# Start local infrastructure (uses Docker)
npm run setup-standalone

# In another terminal, start frontend
npm run dev:frontend

Troubleshooting

Node Won't Start

Error: Cannot bind to port 9944

Solution: Another process is using the port

lsof -i :9944
kill -9 <PID>

Indexer Can't Connect to Node

Error: WebSocket connection failed

Solution: Ensure node is running and accessible

# Test node connection
wscat -c ws://127.0.0.1:9944

Proof Server Version Mismatch

Error: Incompatible ledger version

Solution: Sync proof server to node's ledger version

# Check node's ledger dependency
grep "midnight-ledger" midnight-node/Cargo.toml

# Checkout matching version in midnight-ledger
cd midnight-ledger
git checkout <matching-commit>
cargo build --release

Indexer Out of Sync

Error: Block parsing failed

Solution: Update indexer metadata and reindex

cd midnight-indexer
./scripts/update-metadata.sh
npm run reindex

Docker Issues

Error: Cannot connect to Docker daemon

Solution: Start Docker Desktop or daemon

# macOS
open -a Docker

# Linux
sudo systemctl start docker

Health Checks

Check All Services

# Node health
curl -s http://127.0.0.1:9944/health

# Indexer health
curl -s http://127.0.0.1:8088/health

# Proof server health
curl -s http://127.0.0.1:6300/health

Verify Connectivity

# Test WebSocket to node
wscat -c ws://127.0.0.1:9944

# Test GraphQL
curl -X POST http://127.0.0.1:8088/graphql \
  -H "Content-Type: application/json" \
  -d '{"query": "{ __schema { types { name } } }"}'

Scripts

Use the provided setup script:

bash /path/to/skills/midnight-infra-setup/scripts/setup.sh [action]

Actions:

start - Start all infrastructure
stop - Stop all infrastructure
status - Check service status
logs - View logs
reset - Reset and restart

Present Results to User

Midnight Infrastructure Status:
  Node:         ✓ Running (ws://127.0.0.1:9944)
  Indexer:      ✓ Running (http://127.0.0.1:8088)
  Proof Server: ✓ Running (http://127.0.0.1:6300)

All services are healthy and synchronized.

Next steps:
1. Deploy your contract: npm run deploy:local
2. Start frontend: npm run dev:frontend
3. Connect wallet and interact

References

midnight-infra-dev-tools - Official setup scripts
midnight-node - Blockchain node
midnight-indexer - State indexer
midnight-ledger - Proof server
Token Vault Example - Shielded/unshielded tokens

midnight-infra-setup

Midnight Infrastructure Setup

Architecture Overview