I was watching another MEV opportunity slip away. My Python bot had detected a potential 0.08 ETH arbitrage, but by the time it processed the transaction, the opportunity was gone. This wasn’t the first time, and I knew it wouldn’t be the last.
That’s when I decided to stop fighting Python’s limitations and build MEV Shield — a high-performance MEV detection engine in C++17 that processes 1000+ transactions per second with <15ms latency.
Most MEV detection tools are built in Python or Node.js. They’re great for prototyping and have fantastic ecosystems, but they struggle with real-time performance:
When you’re dealing with mempool transactions that appear for milliseconds, these limitations become deal-breakers. Your bot might detect the opportunity, but it will likely miss the execution window.
I know what you’re thinking: “C++? Isn’t that overkill? Don’t we have modern languages for this?”
Here’s the reality I discovered:
// C++ gives us deterministic performance
void process_transaction(const Transaction& tx) noexcept {
auto opportunity = detect_arbitrage(tx); // Always <15ms
if (opportunity.has_value()) {
alert_system.notify(opportunity.value());
}
// No garbage collection, no unexpected pauses
}
Unlike managed languages, C++ doesn’t have garbage collection. This means consistent, predictable latency that doesn’t spike randomly.
cpp
moodycamel::ConcurrentQueue<Transaction> queue_;
std::atomic<bool> running_{true};
void process_transactions() {
Transaction tx;
while (running_.load(std::memory_order_acquire)) {
if (queue_.try_dequeue(tx)) {
analyze_mev_opportunity(tx); // Lock-free = no contention
}
}
}
Lock-free queues allow multiple threads to process transactions simultaneously without blocking each other.
Modern C++17 isn’t your grandfather’s C++. We have:
During testing, MEV Shield demonstrated:
But the most important metric? Real opportunities caught:
text
[2025-10-27 09:27:38.690] 🚨 HIGH RISK - Profit: 0.0960 ETH | Slippage: 0.3%
[2025-10-27 09:28:26.741] 🚨 HIGH RISK - Profit: 0.1050 ETH | Slippage: 1.9%
[2025-10-27 09:28:38.895] 🚨 HIGH RISK - Profit: 0.1080 ETH | Slippage: 1.1%
These aren’t simulated results. These are actual MEV opportunities that MEV Shield detected and would have captured with proper execution infrastructure.
Many “real-time” monitoring tools actually use HTTP polling, which introduces significant latency. MEV Shield uses proper WebSocket connections to multiple RPC providers with automatic failover.
text
WebSocket → Parser → Detector → Scorer → Notifier
↓ ↓ ↓ ↓ ↓
Thread 1 Thread 2 Thread 3 Thread 4 Thread 5
Each stage runs in its own thread with lock-free queues between them, preventing any single bottleneck.
// Zero-copy string views
void parse_transaction(std::string_view tx_data) {
// No allocations, just view into existing memory
auto tx = Transaction::parse(tx_data);
// ... process transaction
}
// RAII for resource management
class WebSocketConnection {
WebSocketClient client_;
public:
WebSocketConnection(const std::string& url)
: client_(url) { // Automatically connects
}
~WebSocketConnection() {
// Automatically cleans up
}
};
Protect user withdrawals and deposits from MEV attacks with early warning systems.
Get both protection for your own transactions and detection of profitable opportunities.
Warn users about pending MEV risks before they confirm transactions.
Study real MEV patterns with a transparent, open-source implementation.
I’ve open-sourced MEV Shield under GPLv3 because I believe transparent MEV protection benefits everyone in the ecosystem.
Quick Start:
bash
bash
git clone https://github.com/kemboisre-ctrl/mev-shield.git
cd mev-shield
./scripts/quick_start.sh
# Add your API keys to config/config.yaml
./build/mev_shield
The project includes:
In MEV, milliseconds are millions. The difference between 15ms and 150ms latency is the difference between capturing an opportunity and watching it disappear.
With features like auto, smart pointers, and the standard library, modern C++ development is much more pleasant than its reputation suggests.
As blockchain adoption grows, we need tools that can handle the scale. Python and Node.js are great for many use cases, but performance-critical applications deserve performance-optimized foundations.
In the often-opaque world of MEV, transparency is valuable. Open source allows users to verify what the code is actually doing.
I’m excited to see how the community builds upon MEV Shield. Some potential directions:
MEV Shield is available at: https://github.com/kemboisre-ctrl/mev-shield
Whether you’re building trading systems, studying MEV patterns, or just curious about high-performance blockchain applications, I’d love your feedback and contributions.
The crypto ecosystem is evolving rapidly, and performance will increasingly become a differentiator. Sometimes, the right tool for the job is the one that’s been reliably solving performance problems for decades.
What are your thoughts on performance in blockchain applications? Have you encountered similar limitations with interpreted languages? I’d love to hear your experiences in the comments below.
Follow me on GitHub for more updates on MEV Shield and other blockchain development projects.
#Blockchain #MEV #CPlusPlus #DeFi #Ethereum #OpenSource #Performance #Trading
Why I Built a C++ MEV Detection Engine That’s 10x Faster Than Python Alternatives was originally published in Coinmonks on Medium, where people are continuing the conversation by highlighting and responding to this story.


