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Engineering notes

Things we learned the expensive way

Write-ups from real engagements — including the parts that went wrong. No thought leadership, no listicles.

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AI Engineering18 September 20269 min

What actually breaks when RAG meets production

Retrieval demos are easy. Keeping answers correct across a document set that changes daily is where most teams come unstuck — and the fixes are less glamorous than the demos.

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Architecture
4 September 202612 min

Migrating a live monolith without a maintenance window

The strangler fig pattern, applied to a healthcare platform running real consultations. What we routed first, what we left until last, and the two things we got wrong.

DODaniel Okafor
Performance
21 August 20268 min

Where 1.8 seconds actually came from

A line-by-line account of a commerce performance rebuild. Spoiler: the images everyone blamed were worth 200ms, and the third-party tag manager was worth a second.

TRTomás Rivera
Design
7 August 20267 min

Design systems that survive contact with engineers

Most design systems rot within a year. The ones that do not share four properties, and none of them have anything to do with how the Figma file is organised.

PRPriya Raghavan
Platform
24 July 202611 min

Multi-tenant isolation: row-level security or separate databases?

The decision that is hardest to reverse in any SaaS platform, argued from both sides — with the cost and compliance numbers that usually settle it.

AMAarav Mehta
Security
10 July 20266 min

Threat modelling when you have eleven employees

Enterprise security frameworks assume a security team. Here is the stripped-down version that fits a startup afternoon and still catches the things that matter.

MLMarcus Lindqvist
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