Testing & QA

cutting N+1 queries in Next.js API routes with Supabase RPC

when a dashboard starts pulling relational data from Supabase, the naive approach is to fire a separate select per row. the result is a classic N+1…

Enforcing a concrete performance budget for Expo EAS builds and OTA updates

The situation Say you are a mobile engineer on a small React‑Native team that uses Expo Application Services (EAS) for CI‑driven builds and over‑the…

Écrire un article sur les Web Workers en JavaScript

Debouncing vs. Throttling in JavaScript: How to Choose JavaScript interfaces often receive events faster than they need to perform useful work. A se…

Interrupted Runs Belong in the Denominator

A benchmark score that quietly drops interrupted runs is not a conservative score; it is a score whose hardest cases were deleted before anyone coun…

Architecture Patterns for Custom Direct Booking Engines & Hospitality Web Apps

When building web applications for the hospitality sector—ranging from luxury boutique hotels to private villa rentals—developers often face a choic…

AsyncLocalStorage vs Scope.REQUEST in NestJS: Fixing a Multi-Tenant Data Leak Without Killing Performance

A while ago in a high-scale multi-tenant B2B SaaS platform, we ran a high-concurrency benchmark before launching an enterprise data portal. Everythi…

Bevy instancing: drawing 639,000 units with one draw call per mesh

Originally published at tensorust.com . TL;DR: Bevy already instances meshes for you when entities share a mesh and a material. Past a few thousand…

Why We Kept Ternary Bonsai 2 27B After Testing the Faster 9B

October 16, 2026 Our production classifier runs on a single RTX 2080 Ti with 11 GB of VRAM. It is often busy enough that requests spill over to a ho…

Measure the Escalation Rate. A Local-First Router That Never Earns Back Is Just Latency.

A local-first router only pays off if tier 1 absorbs most of your traffic. If your local model answers 20% of prompts and escalates the rest, you di…

HBM Explained: Why High-Bandwidth Memory Is Critical for AI Accelerators

Introduction: Why HBM Matters Artificial intelligence has changed the way computing systems are designed. In traditional servers, system performance…

Technical SEO for Developers: From URL Architecture to Rendering and Indexing

A sitemap points to one URL. The page declares another as canonical. Internal links keep reinforcing a third version. You can change the SEO plugin…

How to Improve Blogger Website Performance with Practical HTML and CSS Optimizations

How to Improve Blogger Website Performance with Practical HTML and CSS Optimizations A Blogger website can look beautiful and still perform poorly o…

Profiling a Slow Application: Stop Guessing, Start Measuring

Your application is slow. Users are complaining. API requests are taking too long, and pages are struggling to load. Your first instinct might be to…

Why a '35GB' Quantized LLM Still OOMs an 80GB GPU: KV Cache, GQA vs. DeepSeek MLA, and the Real VRAM Math

Every engineer deploying open-weights models hits the same rite of passage: You take a 70B parameter model, quantize it to 4-bit ( 70B * 0.5 bytes ≈…

Most PySpark Tuning Advice Starts in the Wrong Place

When I benchmarked PySpark's UDF types earlier this year, I ran the same three workloads (trivial arithmetic, a string transform, a normal CDF) at f…

What Is Event Loop Lag in Node.js? How to Measure It (Part 1)

Your Node.js API gets slow. The database looks fine. So do the downstream services. Yet p99 latency has tripled and even the health check takes 300m…

React Performance Optimization: Practical Techniques for Faster Applications

React applications often start fast, but as features grow, components become more complex, state updates trigger unnecessary renders, and large list…

Your Lab Scores Lie: An Audit Guide to Core Web Vitals That Actually Matter

I work at SEOSage, which builds desktop SEO audit software. The steps below work with any crawler. Google ranks on field data. You are probably meas…

How I Hunted Down 23 N+1 Queries in a Rails App With Claude Code

TL;DR Our Rails app's p95 response time had crept from 280 ms to 1.4 s over a year, and nobody could say why. I paired with Claude Code for four day…

csperf Diff: Comparing Two Runs Without Spreadsheet Chaos

Why this lesson exists In Slack threads you’ll often see two people paste a mean execution time and immediately start a debate. One says “my run is…

Why your tests don't catch N+1 queries (and how to make them)

N+1 queries are easy to merge with a green CI run. The tests covered the endpoint and checked the response. They did not check how many queries it t…

How I got a 100/100 PageSpeed score on a site that updates every single day

Daily-updating sites are the natural enemy of perfect performance scores. Every new image, every new page, every new script is another chance for la…

culpert - rust heap profiling with span awareness and regression tooling

Noise Sources: Affinity, Frequency, and Background Load — How to isolate and quantify non‑compiler variance with csperf

Why this lesson exists Unexplained variance in a csperf run often gets blamed on the compiler, when in fact the machine is the culprit. This episode…

Our Next.js ISR writes hit 325K on Vercel's free plan. Determinism fixed half of it

I run promokoduz.uz , a promo-code catalogue for Uzbekistan in three languages. It is a small site: 111 live codes across 75 brands and about 60 vis…

Why @next/bundle-analyzer wasn't enough for our team (So we built an automated PR bot)

If you've ever worked on a growing Next.js app, you've probably lived through this exact scenario: You’re reviewing a seemingly harmless pull reques…

How I Took a Multilingual WordPress Site to 90+ on Google PageSpeed

Speed is one of the first things visitors notice, and one of the things Google measures. But on a real business website, speed work is never only ab…

MongoDB Indexing Strategies: ESR Rule, Explain Plans, and Performance Tuning

title: "MongoDB Indexing Strategies: ESR Rule, Explain Plans, and Performance Tuning" published: true published_at: "2026-11-20T09:00:00+05:30" desc…

Go regexp too slow? I built coregex, a drop-in replacement. An audit found 16 bugs — here's what broke

Six months ago I published "Go's Regexp is Slow. So I Built My Own" . The project grew, got contributors, beat Rust on several patterns. Tested on G…

Fixing a bad INP in React? Find the slow phase before you optimize anything

Interaction to Next Paint (INP) has been a Core Web Vital since March 2024, when it replaced First Input Delay. It's also the one teams find hardest…