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When the disk fills up: pressure and tenant isolation in Squirix preview.7
In my preview.6 article , I wrote about what happens after a write is accepted: binary WAL frames, group commit, crash recovery, and durable retries. …
Treat Health-Data Revocation as a Distributed Convergence Protocol
Counterexample: a connector grant is revoked at epoch 8, but an import message created under epoch 7 is delayed. The primary store deletes its copy, t…
Kafka record headers in Stateful Functions: closing a five-year-old gap
Apache Stateful Functions never let a function see Kafka record headers, and never let it set them. Five years, no headers. StateFun Actors 3.4.0-KZM-…
Make an Outbox Relay Lease Expire Without Violating Delivery Invariants
Relay A claims outbox row 42 and publishes its message. Before A records completion, its lease expires. Relay B claims row 42 and publishes it again. …
Building Reliable Event-Driven Systems: Event Schemas, Versioning, Contract Testing and Events vs Commands (5/5)
In this final article, we're going to explore Production practices 22. Events Are Delivered, Not Guaranteed A common misconception in event-driven arc…
Distributed Move Protocol
The Hidden Complexity of Moving State in Distributed Systems Why a simple “move” becomes a distributed protocol when source and destination live on di…
Building Reliable Event-Driven Systems: Event Schemas, Versioning, Contract Testing and Events vs Commands (part-4)
In this article, we're going to explore Contract Testing Contract testing ensures that event contracts remain stable as systems evolve. Producers rece…
What happens after a write? Reworking Squirix's WAL in preview.6
In my first Squirix article , I wrote about why Squirix keeps a strict boundary between the client and the server. Applications use a typed client ove…
Test Saga Compensation When Payment Succeeds but Inventory Times Out
An order reserves inventory, charges payment, then times out waiting for reservation confirmation. Cancellation begins. A late inventory success arriv…
QUIC-Based NAT Traversal: How PUNCH_ME_NOW Frames Are Standardizing Hole Punching
TL;DR: NAT traversal has historically relied on STUN/TURN/ICE running as an external signalling layer bolted onto whatever transport protocol you choo…
# Agentic Systems for Big Query Handling in Distributed Environments: The Complete Engineering Guide
A data engineering team at a global logistics company submits a query: "Identify all shipments delayed by more than 48 hours in the last quarter, cros…
Building Reliable Event-Driven Systems: Event Schemas, Versioning, Contract Testing and Events vs Commands (part-2)
This is part-2 of the article series on "Building Reliable Event-Driven Systems". In this article, we're going to explore Event Schemas . 5. Designing…
We hit an at-least-once delivery trap. Here is how we fixed the race conditions.
If you are running an event-driven architecture with message queues like Kafka, you already know the drill, scalability is awesome, but network partit…
Treat Per-Task Model Switching as a Concurrency Protocol
Changing the model for a running AI task is not a settings update. It is a distributed operation: read current task -> prepare credentials/config -…
Failure Engineering Explained by Uncle to Nephew — Episode 1: Why Failures Are Normal
New series, same two people from the Node.js Internals series. Where that series answered "how does the system work?", this one answers "how does the …
gRPC Internals and Performance
Gearing Up for Speed: A Deep Dive into gRPC Internals and Performance Ever feel like your microservices are gossiping at a snail's pace? You've got th…
🚀 We're Hiring Software Engineers at 10xHire
👉 Apply Here First Application Form: https://forms.gle/QJNF7TXVBTgbLoaC7 At 10xHire , we're building the next generation of technical hiring. We belie…
Beyond TTL: Explicit Cache Invalidation
Most engineers default to TTL for cache invalidation. But a simple Time-To-Live guarantees stale reads for a duration, which is unacceptable for criti…
Core Concept: Leader Election via Consensus
It's not agreeing on a transaction that's often the most expensive consensus operation in a distributed system, it's agreeing on who gets to decide . …
How I decide what to build, and what to throw away, as a solo founder building an L1
I work on NOVAI alone right now. No team to argue with, no senior engineer to catch the thing I can't see, no reviewer to tell me the idea I am in lov…
Eventual Consistency Is Misunderstood by Most Engineers
I've interviewed dozens of engineers at the senior level. When I ask them to explain eventual consistency, most recite the textbook answer: "data will…
Prioritizing Abstractions Over Complexity: Addressing Illusions in Distributed Systems Platform Design
Introduction In the world of distributed systems, complexity is the beast we’re all trying to tame. Teams building platforms often fall into the trap …
"Done" Is Not a State
On December 16, 2024, a developer filed a bug report against Trigger.dev, the open-source background job framework. A routine nightly server restart h…
The Bug Behind the Bug: Why Protocol Failures Rarely Live in One Layer
Blockchain incidents are often explained too simply: “consensus stopped,” “the VM produced the wrong state,” or “a malformed transaction crashed valid…
Orchestrate Saga Compensation Timeouts in Real Time (Kiponos Java SDK)
A checkout saga spans inventory, payment, shipping, and loyalty. Downstream latency shifts every hour. Black Friday is not the day to discover your pa…
System Design Interview Questions by Level: Junior, Mid-Level, Senior, and Staff
System Design Interview Questions by Level: Junior, Mid-Level, Senior, and Staff Not every system design interview evaluates the same thing. A junior …
Cinema Seat Reservation System — Part 2: Transitioning To Production-Scale and Deploying on Azure Cloud
Introduction This is the second part of sharing my journey to create a microservices-based backend system, in the previous part, I introduced the syst…
The Physical Laws of AI Migrations: Architecting an LLM Orchestrator that Survives Reality
Large codebase migrations are not typing problems; they are distributed state machine problems. When you execute a multi-step, multi-PR refactor with …
From Feature Delivery to Platform Engineering.
The Problem: Feature Velocity Was Creating Structural Debt The system originally started as a simple feature delivery backend: A Django API powering a…