Sign in

David Mello

@reallymello.bsky.social
8 followers 1 following 18 posts

Director of Quality Engineering. Writing about test automation, accessibility testing, and software quality at www.davidmello.com Also: DIY solar, home automation, and Florida living.

PostsRepliesMedia
David Mello @reallymello.bsky.social · 03/10/2026
I built a floating ghost hologram for my yard with gray tulle, scrap wood, and a projector 👻🎃 Surprise: my first projector was way too dim. Here's the build, where to put the projector, and how bright it needs to be. #halloween www.davidmello.com/diy-home-upg...
davidmello.com
How to Make a Halloween Hologram With a Projector and Tulle
Build a floating ghost hologram for your yard with tulle, scrap wood, and a projector. Real night tests show how bright your projector needs to be, plus 3D pumpkins.
000
David Mello @reallymello.bsky.social · 21/09/2026
How do you keep tests that can't run in parallel (they change global state, feature flags, web.config) from forcing your whole #Playwright suite back to serial? Three ways to mix serial and parallel tests, with pros and cons and a demo repo www.davidmello.com/software-tes...
davidmello.com
Run Parallel and Serial Tests Together in Playwright
Playwright tests that change global state break parallel test runs. Learn different ways to run serial and parallel tests together without failures.
000
David Mello @reallymello.bsky.social · 19/09/2026
Years ago we tried #predictive #test selection to fix an 8-hour CI loop (run test subsets). It worked, until it exposed intra-test dependencies we never knew existed. A #StarEast talk finally gave that problem a name, and detailed four different approaches pro/con www.davidmello.com/software-tes...
davidmello.com
Test Selection: Run Fewer Tests, Catch the Same Bugs
A framework for running fewer tests without missing real bugs, and the one prerequisite that has to be true first. StarEast 2026 lessons.
001
David Mello @reallymello.bsky.social · 06/09/2026
An #AI-generated #K6 load test passed every check. The app fell over in production. A try/catch had been swallowing the errors. Wrote up what that taught me about AI guardrails, from a #StarEast talk on using #Claude Code across the performance testing lifecycle: www.davidmello.com/software-tes...
davidmello.com
AI Performance Testing Guardrails Every Tester Needs
An AI-generated performance test missed a real bug, and the app broke in production. StarEast 2026 lessons on the guardrails that would have caught it.
000
David Mello @reallymello.bsky.social · 30/08/2026
I reused our #Playwright functional tests to drive load testing instead of building a separate suite. Turns out a SAS performance engineer did the same thing independently, different tools, same conclusion. Wrote up what we both learned (and where it breaks down): www.davidmello.com/software-tes...
davidmello.com
Reuse Your Playwright Tests for Load Testing
Reuse existing Playwright functional tests for load testing instead of building a parallel suite. My own experience, validated by a StarEast 2026 talk.
000
David Mello @reallymello.bsky.social · 11/08/2026
Decided to see if these newer battery-powered pool cleaning robots with AI features are worth the cost over traditional passive suction-side cleaners. I rolled the dice on the #Aiper #Scuba and #EcoSurfer Experts Duo bundle where one cleans the pool and the other skims bugs off the waterline
davidmello.com
Aiper Experts Duo Review: Worth the Upgrade?
I replaced my Poolvergnuegen suction-side cleaner with the Aiper Experts Duo robotic pool cleaner (Scuba V3 + EcoSurfer S2). Unboxing, first-week results.
000
David Mello @reallymello.bsky.social · 19/07/2026
With hot summer temperatures, sometimes adding an attic gable fan helps with heat load and cooling efficiency in your house, especially if your AC ducts run through the attic space. Here is a calculator to help find the right size for your attic space www.davidmello.com/tools/attic-...
davidmello.com
Attic Fan CFM Sizing Calculator
Calculate the minimum and recommended CFM for a gable or roof attic fan based on your attic square footage and climate, with fit checks against popular fan models.
000
David Mello @reallymello.bsky.social · 02/07/2026
#Ubiquiti #UniFi released an entire lineup of #5G backup internet devices with great specs, but they chose to pair them with terrible data plans. This is why we can't have nice things. www.davidmello.com/networking/u...
davidmello.com
UniFi 5G Backup: Great Hardware, Bad Plans
Ubiquiti's new 5G backup hardware is genuinely good. The bundled data plans are not. Here's what plans actually work, including an unlimited option for $14.95/month.
000
David Mello @reallymello.bsky.social · 29/06/2026
Used a #FLIR camera to see how much heat a #PortableAC exhaust duct radiates back into the room it's supposed to be cooling. Posted tips and video evidence for #hvac efficiency to keep your spaces cool in summer. www.davidmello.com/diy-home-upg...
davidmello.com
How to Improve Portable AC Efficiency, Updated
Portable AC efficiency fixes ranked by cost and effort: duct insulation, the intake hose most people skip, window sealing, and when to upgrade to a mini-split.
100
David Mello @reallymello.bsky.social · 22/06/2026
Have you, or someone you know, been told that #Playwright CLI less expensive than Playwright MCP during #AI driven test development, but haven't had the time to dig into why? Well, @automationpanda.bsky.social covered it during his #StarEast2026 tutorial. www.davidmello.com/software-tes...
davidmello.com
Playwright AI Testing on a Budget: Locators vs. Computer Vision — StarEast 2026
Playwright's MCP server can burn your AI budget fast. StarEast 2026 lessons on efficient AI testing, and why locators still beat computer vision.
020
David Mello @reallymello.bsky.social · 20/06/2026
When the feels like temperature outside is already 106F outside I'm glad I invested in my @airspool.bsky.social #solar air conditioner www.davidmello.com/diy-home-upg... In Florida yesterday with the feels like at 106F the garage was able to stay at 72F!
davidmello.com
DIY Solar AC Installation: Garage Mini Split Review (South Florida, 1 Year Later)
Airspool mini-split solar AC review from a South Florida garage gym install. Full DIY solar AC installation guide, real performance data, financial payback math, and how it held up a year later.
000
David Mello @reallymello.bsky.social · 19/06/2026
"What is an eval? It is a regression suite...codename because developers didn't like testers so they came up with a different name." Kevin Pyles dropped that line at #StarEast2026 🤪 I also built a Dracula chatbot. www.davidmello.com/software-tes... #QA #PromptEngineering #VibeCoding
davidmello.com
Getting Dirty with AI Testing: A StarEast 2026 Trip Report on Evals, Vibe Coding, and Prompt Engineering
StarEast 2026 trip report: what a hands-on AI testing tutorial taught me about prompt engineering, evals, and building an AI chatbot as Count Dracula.
010
David Mello @reallymello.bsky.social · 14/06/2026
Interesting tutorial on using AI Vision to side-step brittle test selectors at #StarEast2026 — including testing non-web apps where there's no DOM to rely on. www.davidmello.com/software-tes... #TestAutomation #SoftwareTesting
davidmello.com
Beyond Brittle Selectors: AI Vision Testing vs Playwright MCP — StarEast 2026
Brittle selectors slowing your team down? My notes from StarEast 2026 on AI vision testing vs Playwright MCP — and where to start.
020
David Mello @reallymello.bsky.social · 25/05/2026
Had the opportunity to test my first AI agent #chatbot. The process felt familiar with the key difference of non-deterministic output. Captured my first impressions solving that with a #Promptfoo and #Playwright test suite in this post www.davidmello.com/software-tes...
davidmello.com
How to Test AI Chatbots and Agents: A Real-World QA Engagement
Testing an AI chatbot with Promptfoo and Playwright: oracle problem, guardrail testing, bias detection, and accessibility — lessons from a real two-week engagement.
000
David Mello @reallymello.bsky.social · 18/05/2026
Interview question: "What would you stop doing when UI tests are flaky?" Drop your answer below, then see how it compares to what other QA engineers said for this awkward question 👇 davidmello.com/software-tes...
davidmello.com
What Would You Stop Doing When UI Tests Are Flaky?
Most QA engineers answer this interview question confidently wrong. Here's what
010
David Mello @reallymello.bsky.social · 17/05/2026
#Lighthouse is a robot vacuum. It covers a lot of ground automatically — but you still need to do the spots it can't reach. axe detects ~57% of real accessibility violations at best. Here are the #Playwright test patterns for the other 43%: www.davidmello.com/software-tes...
davidmello.com
Playwright Accessibility Testing: What axe and Lighthouse Miss
axe and Lighthouse miss 60–70% of WCAG violations. Learn the limitations of automated accessibility testing and how to write smarter Playwright tests.
002
David Mello @reallymello.bsky.social · 18/04/2026
I've been running #UniFi Talk for 4 years now as my home VoIP service. Still on the original $9.99/mo, still blocking every robocall, and the app reliability issues from the early days seem to have been ironed out. Full impressions + original review: www.davidmello.com/networking/u...
davidmello.com
UniFi Talk Review with UTP-Touch VoIP phone
UniFi Talk review covering the UTP-Touch VoIP phone, UniFi Talk pricing, setup, number porting, and features on a Ubiquiti Dream Machine.
000
David Mello @reallymello.bsky.social · 16/04/2026
If your team is hand-writing API tests from an OpenAPI spec, there's a better way. Schemathesis reads your spec and generates test cases automatically — boundary conditions, fuzzing, stateful sequences. davidmello.com/software-testing/test-automation/automated-api-testing-with-schemathesis
davidmello.com
Stop Writing API Tests Manually — Let Your OpenAPI Spec Do the Work
Schemathesis automates API testing by generating test cases directly from your OpenAPI spec — covering edge cases, schema violations, and server errors you'd never think of or have the time to write m...
000