quant.engineering

Schema Evolution Under Live Order Flow

rundef — Sun, 12 Apr 2026 00:00:00 -0400

Schema changes don't roll out atomically in real systems. Old and new versions coexist across services, making backward compatibility and long-term correctness unavoidable constraints.

Streaming Under Adversity: Building Systems That Survive Reality

rundef — Sat, 21 Mar 2026 00:00:00 -0400

Financial streaming systems must remain correct when reality intervenes. This article dissects crash mid-window recovery, checkpoint corruption, idempotent effects and deterministic replay when failures occur.

Designing Fault-Tolerant Async Trading Services in Python

rundef — Sat, 07 Mar 2026 00:00:00 -0500

A production-ready async runtime architecture with explicit supervision and restart discipline, built to keep trading systems correct under failure, stress and load spikes.

Inside DeFi's Hidden Economy: MEV, Mempools, and the Battle for Blockspace

rundef — Sat, 21 Feb 2026 00:00:00 -0500

Step inside DeFi's hidden economy: how mempools, MEV and Flashbots turn transaction ordering into a latency-driven execution game where speed and visibility decide outcomes long before settlement.

From Blocks to State: A Mental Model for Blockchain Systems

rundef — Sat, 07 Feb 2026 00:00:00 -0500

Blockchains are often explained through protocol-specific concepts like blocks or slots. This article reframes them as distributed state-transition systems, where ambiguity and delayed agreement exist to varying degrees across chains.

The Hidden DAG Behind Every Modern Trading System: How Market Data Is Ingested at Scale

rundef — Sat, 24 Jan 2026 00:00:00 -0500

Modern trading systems rely on directed acyclic graphs (DAGs) that branch, merge, and transform real-time feeds into many parallel consumers: matching engines, risk checks, analytics, surveillance, and storage. These ingestion DAGs exist to isolate failure, control fan-out, and preserve latency and correctness under extreme market conditions.

Flow Control in Low-Latency Systems: Batching, Conflation, and Backpressure

rundef — Sat, 10 Jan 2026 00:00:00 -0500

Low-latency systems fail when work becomes unbounded. Batching, conflation, and backpressure are mechanisms that keep systems stable under bursty, adversarial load. Without them, tail latency and cascading failures are inevitable.

Observability at Scale: Distributed Telemetry for Modern Trading Infrastructure

rundef — Sat, 13 Dec 2025 00:00:00 -0500

How do trading systems observe themselves in real time? This article breaks down the telemetry architecture that keeps distributed systems visible under extreme latency pressure.

How Exchanges Turn Order Books into Distributed Logs

rundef — Sat, 06 Dec 2025 00:00:00 -0500

Every modern exchange is a distributed database in disguise. This article reveals how trading engines transform chaotic streams of buy and sell orders into a perfectly ordered, replayable log, ensuring fairness, determinism, and market data reliability.

Latency Profiling in Python: From Code Bottlenecks to Observability

rundef — Sat, 29 Nov 2025 00:00:00 -0500

Understanding where time disappears in Python systems requires measuring both CPU and I/O behavior. Profilers, metrics pipelines, and continuous observability tools expose the performance patterns hidden inside production workloads.

Understanding Latency: From Wire to Code

rundef — Sat, 15 Nov 2025 00:00:00 -0500

Every microsecond counts, but where do they actually go?

Tracing the journey of a message from the network wire to application code reveals how NICs, interrupts, syscalls, and runtimes introduce latency at every hop.

Dissecting the Infra of DeFi Protocols

rundef — Sat, 08 Nov 2025 00:00:00 -0500

Most DeFi discussions stop at smart contracts. This article goes deeper: through the data pipelines, executors, keepers, and coordination layers that make protocols run. If you're a software engineer, you'll see how DeFi architecture mirrors the systems you already know.

What Database Scaling Looks Like When Milliseconds Mean Millions

rundef — Sat, 01 Nov 2025 00:00:00 -0400

Financial systems process billions of time-series data points with sub-millisecond query requirements: constraints that break traditional databases. Scaling these workloads requires different architectural choices, from vertical scaling to intelligent sharding schemes and specialized layouts for market data.

Introduction to DeFi Engineering

rundef — Thu, 23 Oct 2025 00:00:00 -0400

An introduction to the engineering landscape in DeFi protocols: the distinct engineering roles (protocol, infrastructure, execution), the complete technology stack from smart contracts to off-chain systems, core primitives like liquidity pools and oracles, and what makes building in this space fundamentally different from traditional fintech.

How to Build Execution Systems for Crypto Trading at Scale

rundef — Sun, 12 Oct 2025 00:00:00 -0400

How do you execute $100M orders across 10+ crypto exchanges without moving the market? This deep-dive covers the infrastructure behind institutional trading systems: market data pipelines, smart order routing, execution quality metrics, and building for failure.

Ring Buffers 101: The Building Block of Low-Latency Systems

rundef — Sat, 04 Oct 2025 00:00:00 -0400

Ring buffers are a foundational data structure in low-latency systems. Their memory layout enables predictable performance and high throughput in real-time workloads such as trading engines, telemetry pipelines, and network processing.

Message-Oriented Architectures in Trading Systems: Patterns for Scalability and Fault Tolerance

rundef — Sat, 20 Sep 2025 00:00:00 -0400

Modern trading systems rely on message-oriented architectures to move market data, orders, and risk events between services with predictable latency. Delivery guarantees, broker architectures, and ordering constraints shape how these systems behave under load.

Canton: A Distributed Ledger for Global Finance

rundef — Sun, 07 Sep 2025 00:00:00 -0400

Traditional settlement takes days because banks cannot trust shared state. Canton Network addresses this with domain-based consensus and cryptographic privacy, enabling real-time settlement without sacrificing confidentiality.

Interdependence of returns across multiple strategies

rundef — Mon, 03 Mar 2025 00:00:00 -0500

Low correlation between strategies does not guarantee independence. Hidden dependencies between trading strategies can create concentrated portfolio risk, especially during regime shifts where correlations suddenly converge.

Setting up an Ubuntu 24.04 EC2 instance for algorithmic trading with Interactive Brokers

rundef — Fri, 28 Feb 2025 00:00:00 -0500

Provisioning cloud infrastructure is a common step when moving trading systems from local development to production. This guide shows how to deploy an Ubuntu 24.04 EC2 instance and connect it to Interactive Brokers.