Idempotency keys done right: exactly-once effects over at-least-once networks
Why "just retry" creates duplicate payments, and a PostgreSQL-backed design for idempotency keys that survives double clicks, timeouts, crashes and…
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Split-Brain Needs a Cluster. Mine Happened on One Server.
Today I want to talk about split-brain. The name sounds dramatic, and the problem is dramatic too. One system splits into two halves, and each half…
Every line of my recovery code was correct. It failed every single time."
I run an automated trading system on a paper account. Two pipelines, a handful of small single-purpose agents, no human in the loop once it starts.…
Moving Carefully and Proving It: The Reality of Scaling Fintech Infrastructure
Building backend systems for fintech is fundamentally different from almost any other domain. The stakes are absolute, the edge cases are catastroph…
Deep Dive: Precision Timing Subsystem Modules & IEEE 1588 ArchitectureIn modern distributed computing
Here is a complete, publication-ready Medium article based on the guide to Precision Timing Subsystem Modules and IEEE 1588 architecture.Deep Dive:…
Idempotent APIs: Complete Guide to Building Reliable and Duplicate-Safe Distributed Systems
Author: Gupta Abhishek Premkumar Published: September 2026 Reading Time: 18 Minutes Tags: API, Distributed Systems, Microservices, Spring Boot, REST…
Your Agent's Retry Logic Is an Event-Driven Systems Problem
Most of the event-driven architecture I've built started the same way: a synchronous call chain that worked fine in a demo and fell over under real…
Make Sandbox Epoch a Fencing Token Before Free Compute Vanishes Mid-Write
Here is the event order I use as a paper counterexample when someone treats a free sandbox as durable storage. The planner sends apply_patch , the s…
Transactional Outbox Pattern: Memory Queue for Speed, PostgreSQL for Recovery
In distributed systems, the Transactional Outbox Pattern is a common way to reliably publish events after a database transaction. The idea is simple…
Circuit Breaker Pattern Explained: How to Prevent Cascading Failures in Distributed Systems
Circuit Breaker Pattern What happens when one service fails, but your entire system keeps calling it anyway ? Imagine your payment service is down.…
I Thought Redis Would Save My API. Just 500 Requests Proved Me Wrong.
As our series continues, Deep-Dive Backend Systems Roadmap. I created the simplest weather API backend, calling the other API to get weather data an…
Circuit Breaker Pattern
One-liner: A circuit breaker stops calling a failing service to give it time to recover — instead of hammering it with requests that are guaranteed…
Building Faultline: A Reusable Chaos-Injection and Linearizability-Checking Harness
Building Faultline: A Reusable Chaos-Injection and Linearizability-Checking Harness Faultline is an open-source Go harness that injects faults into…
Metrice: Zero-dependency post-quantum P2P mesh network
Metrice is a decentralized peer-to-peer (P2P) mesh networking protocol engineered with zero external npm dependencies (Zero-Dependency), running nat…
Keeping a Legacy Cache Consistent During an Incremental Migration
During an incremental system migration, I ran into a subtle consistency problem: our new service could successfully update the database while the le…
Your API will be called twice. Here's how to make it run once.
The bug report that has no bug Someone got charged twice for one order. The report lands with a screenshot and an angry emoji, and you start pulling…
Handling Partial Failures in Distributed Systems
Quick Answer: To handle partial failures in distributed systems, avoid complex distributed transactions. Instead, design for the "unhappy path" usin…
Seven Ideas That Keep Distributed Systems From Falling Over
Hello, I'm Maneshwar, and I'm building LiveReview — a blast-radius aware AI code review built for your business-critical systems. Star us to help de…
Any Language, One Store: How Zaris Speaks the Redis Protocol
Zaris is a distributed key/value store built for .NET, with its own binary protocol and native .NET clients. With 2.0.0, every Zaris node can also e…
Kafka vs RabbitMQ vs NATS (2026): Performance, Use Cases, Latency, Throughput & Microservices
Kafka vs RabbitMQ vs NATS (2026): Performance, Use Cases, Latency, Throughput & Microservices Choosing the right messaging system can have a maj…
VRP Is Ready for External Validation — One Company Can Be the First to Pilot It
VRP Is Ready for External Validation — Who Will Be the First to Pilot It? My name is Vitalijus Riabovas. I am the independent architect and creator…
My QUIC transport had never once been executed. Here's what happened when I ran it.
I've written before about SMESH, a coordination protocol modelled on mycorrhizal networks — the fungal web that lets trees in a forest warn each oth…
The Outbox Pattern Is Not Enough
The textbook version of the transactional outbox is tight. You save the domain entity and an outbox row in one local transaction. A background sched…
My idempotency library had one job. A dropped connection made it run the payment twice.
quayside is my idempotency library for Node.js. The whole API fits in one sentence: execute(key, fn) runs a function exactly once per key — if it al…
"half-open" twice is not the same state: the bug that shaped breakwater 1.0
breakwater is my resilience toolkit for Node.js — retry, circuit breaker, timeout, bulkhead, rate limiting, stale-while-open caching, all composable…
TOCTOU in Payment Systems: When Validation Becomes Stale Before Commit
The formal problem: CWE-367 Time-of-check to time-of-use (TOCTOU) is a formally catalogued class of race condition, CWE-367 , first documented in 20…
Building Sluice: QoS-Aware Capacity Governance for Self-Hosted LLM Inference
📦 Project: https://github.com/VampiricCyborg/sluice 1. The Problem: When Capacity Becomes the Bottleneck A self-hosted vLLM deployment runs on a GPU…
A Floor Beneath Every Person: Design Choices in the First Social Resource Floor Blueprint
TL;DR — I've been building the Social Resource Floor: an open blueprint for coordinating one person's access to basic survival resources — food, hou…
Horizontal Scaling: Solving One Problem, Creating Another
When learning system design, we are almost always fed the exact same doctrine: start with one API + one Database, then as traffic increases, add a L…
I Built a Concurrent Resource Scheduler in Go Using Sharded Priority Heaps
Support on GitHub: github.com/phero20/concurrent-resource-scheduler (Give it a star if you find it useful!) View Docs: pkg.go.dev/github.com/phero20…