Bitcoin Devnet

Overview

Bitcoin Devnet is a private Bitcoin Signet network designed for rapid application development and testing. Unlike public testnets or regtest, Devnet provides a realistic peer-to-peer network environment with automatic 10-second block generation, simulating real-world blockchain behavior including network latency, mempool dynamics, and block propagation.

Built on Bitcoin Signet (BIP 325), Devnet uses signature-based block validation instead of proof-of-work, enabling predictable block times while maintaining realistic network topology. The network consists of 3 interconnected Bitcoin Core nodes (node1, node2, node3) running on Fly.io infrastructure, with a Spring Boot controller service managing automated block generation.

Perfect for developers building wallets, payment processors, Lightning applications, or testing transaction broadcasting, mempool behavior, and multi-node synchronization without waiting for unpredictable testnet confirmations.

Why Devnet Instead of Regtest or Testnet?

• Predictable Block Times: Blocks generated every 10 seconds automatically - no manual mining required. Send a transaction at 12:34:25, expect confirmation at 12:34:35.
• Real Network Topology: 3-node peer-to-peer network simulates realistic block propagation, mempool broadcasting, and network latency (unlike single-node regtest).
• Controlled Environment: Private Signet network isolated from public testnet chaos - no spam, no reorgs, no waiting for blocks.
• Automated Management: REST API controller handles block generation automatically - focus on your application, not infrastructure.
• Production-Like Testing: Test multi-node scenarios, transaction propagation, and mempool behavior in a realistic but controlled environment.

Network Architecture

The Devnet consists of 4 components running on Fly.io:

• bitcoin-devnet-node1 (Alpha): Primary Bitcoin Core 27.0 Signet node with RPC enabled
• bitcoin-devnet-node2 (Beta): Relay node connected to node1 and node3
• bitcoin-devnet-node3 (Gamma): Relay node connected to node1 and node2
• mnemore-devnet: Spring Boot controller service that calls generatetoaddress RPC every 10 seconds

All nodes use a deterministic signetchallenge generated from seed mnemore-devnet: 5121020e75a502400f97083b195342e58519c6a532d89e6f1fd016e5505c4186da6251ae

Technical Specifications

Devnet Controller API

The mnemore-devnet service provides a REST API for monitoring and controlling the network. Block generation runs automatically every 10 seconds, but you can also control it manually.

Base URL: https://mnemore-devnet.fly.dev

Monitoring Endpoints

# Check mining status and block count
curl https://mnemore-devnet.fly.dev/api/devnet/status

# Response:
{
  "isMining": true,
  "blockCount": 1523,
  "lastBlockTime": "2025-10-28T14:23:35Z",
  "blockIntervalSeconds": 10,
  "miningAddress": "tb1q..."
}

# Get blockchain information
curl https://mnemore-devnet.fly.dev/api/devnet/blockchain/info

# Get connected peers (should show 2 peers)
curl https://mnemore-devnet.fly.dev/api/devnet/peers

# Get network information
curl https://mnemore-devnet.fly.dev/api/devnet/network/info

Control Endpoints

# Mine a single block immediately
curl -X POST https://mnemore-devnet.fly.dev/api/devnet/mine-block

# Stop automatic block generation
curl -X POST https://mnemore-devnet.fly.dev/api/devnet/stop-mining

# Start automatic block generation
curl -X POST https://mnemore-devnet.fly.dev/api/devnet/start-mining

# View current configuration
curl https://mnemore-devnet.fly.dev/api/devnet/config

Roadmap

Using the Devnet

Connect to any of the three nodes via RPC to broadcast transactions, query the blockchain, or test your application:

# Connect to node1 (primary)
bitcoin-cli -signet -rpcconnect=bitcoin-devnet-node1.fly.dev \
  -rpcport=38332 -rpcuser=bitcoin -rpcpassword=*** \
  getblockchaininfo

# Broadcast a transaction
bitcoin-cli -signet -rpcconnect=bitcoin-devnet-node1.fly.dev \
  -rpcport=38332 -rpcuser=bitcoin -rpcpassword=*** \
  sendrawtransaction <hex>

# Transaction will be included in next block (within 10 seconds)
# Example: Send at 14:23:25 → Confirmed at 14:23:35

# Check mempool
curl https://mnemore-devnet.fly.dev/api/devnet/mempool/info

# Watch blocks being generated in real-time
watch -n 1 'curl -s https://mnemore-devnet.fly.dev/api/devnet/status | jq .blockCount'

Testing Scenarios

• Transaction Broadcasting: Send transactions to node1, verify they propagate to node2 and node3 within seconds
• Mempool Behavior: Test transaction replacement (RBF), fee estimation, and mempool eviction
• Block Propagation: Verify blocks generated on node1 reach node2 and node3 within 1-2 seconds
• Multi-Node Sync: Test wallet synchronization across multiple nodes
• Predictable Timing: Build time-sensitive applications knowing exactly when blocks will arrive