Giacomo Debidda

⚡ Performance audit of an Italian news website giacomodebidda.com/posts/performa… In this article I analyze both field data from the CrUX #BigQuery dataset, and lab data from dozens of @RealWebPageTest test runs. Hope you like it! #webperf #perfmatters

🛡️ Slides and code for my presentation "HTTP headers for web security" are online here: …e-headers-for-web-security.vercel.app If you have any questions or suggestions, feel free to send me a message or open an issue on GitHub. github.com/jackdbd/http-r…

🛡️ Next Monday I’ll give a talk on HTTP response headers for #websecurity Topics: - Content-Security-Policy - Reporting-Endpoints & Reporting API - CORP, COEP, COOP - same-origin and CORS - cross-origin isolation Plus: cool demos! 😎 eventbrite.it/e/biglietti-pi… #infosec #XSS

Cosa se ne fa un programmatore JavaScript di conoscere un linguaggio compilato come Zig? Se sei scettico, interessato, o semplicemente curioso di come puoi usare Zig in un progetto JavaScript (o TypeScript), fai un salto a Bologna JS il 18 Ottobre. meetup.com/bologna-js-mee…

@TheRealNooshu The desktop version and the mobile version could even be entirely different websites, built with different technologies. With Backends For Frontends (BFF) incoming requests with different user-agents (or other headers) might hit a different API gateway. microservices.io/patterns/apiga…

TIL: Lighthouse runs different #a11y audits depending on if mobile / desktop is selected. I assumed, due to responsive design, it would just run the same audits for both. The underlying HTML is the same, after all?

@RealWebPageTest @data_dome Preserving the user agent did the trick, thanks!

@jackdbd @data_dome Hello Giacomo. Pls try the following: 🔸 go to the adv panel, under Advanced Configuration 🔸 ✅ the 'Preserve original User Agent string' That should solve the issue. Pls ping us back if not. Thx!

Hey @RealWebPageTest users, I'm trying to audit a product page of an eCommerce, but @data_dome thinks WebPageTest is a bot and immediately returns an HTTP 403. Is there anything I can do to change its mind? 😅 #webperf

The most effective software engineers I know always had a tendency to revert to writing "C" style code. Nothing seems to come close in terms of readability / maintainability.

@saltyAom Thanks, super useful! What kind of state are managing with jotai? Form's state is managed by react hook form and server's state by tanstack, right?

Ok, Redemption Arc: Here's my thought after creating the same simple with React Native and Flutter:

@Gonzohall @levelsio Never been to Da Nang, but it seems a very cool place. What's missing in your opinion?

@levelsio Interesting. There was a time, 4 years ago, when people had to leave Chian Mai that we thought Da Nang was the future hub. We were wrong.

🇻🇳 Saigon is absolutely booming now nomadlist.com/trends/ho-chi-…

@ohmypy Nice! This is also useful for writing Common Table Expressions

One of my favorite little features in Sqlime is the ability to select and execute a query fragment. Really helps to debug complex queries. And was easy to implement! If only all features could be like this.

@DmytroKrasun Was it managed kubernetes (e.g. GKE) or DIY kubernetes?

I worked in a startup that began by operating Kubernetes and 150+ microservices. Can you predict what happened to the startup? And how fast was the delivery speed?

The tool is online at: docs.google.com/spreadsheets/d… Comments and suggestions very much appreciated. Here is the dialog that I'm currently using to query the CrUX #bigquery dataset. The UI needs some love...

The tool stores the WPT/JS scripts when you submit the form in the sidebar. On a second visit of the same website - not necessarily the same URL - the tool loads the WPT/JS script from localStorage.

I'm making a #webperf tool to use @RealWebPageTest from Google Sheets. You specify WPT profiles in a spreadsheet, select them using checkboxes, copy and paste the URL to test, then hit submit.

@HenriHelvetica @RealWebPageTest Hi Henry. Sure! In fact I was looking for some feedback. cal.com/giacomodebidda… The tool is also able to fetch field performance data by querying the BigQuery CrUX dataset. I think this feature is quite clunky to use at the moment, that's why I didn't show it here.

@jackdbd @RealWebPageTest Oooh. This looks super interesting! Up for a chat about it?

@JLarky I'm wondering why those two service worker requests take 3x the time

useEffect is fine, only juniors don't know how to use it. Meanwhile rocket scientists:

@philkellr You can use this FFMPEG command lists.ffmpeg.org/pipermail/ffmp… Another cool tool is Fessonia, a Node.js wrapper for FFMPEG developed by the folks at TED. I'm not sure what kind of animations you'd want in the video. Transitions? For those you will need a FFMPEG filter I think.

I want to take a set of photos And turn them into a video Ideally with animations Fully automatized (ideally with python) Any recommendations?

@anthony_hagi @t3dotgg Cit. "But is it web scale?"

@t3dotgg Store it on /dev/null, it’s 1000x faster than any other place to store it. It’s also free, and you never have to add on extra storage!

Anyone know somewhere better to store your images? 😉

@philkellr But it could also be gunicorn's fault. See rachelbythebay.com/w/2020/03/07/c…

@philkellr You could try clinicjs.org and have a look at the flamegraph and the HeapProfiler. Otherwise, if you are willing to stop Node, you could launch the Node.js app with --trace-gc, record a heap snapshot and drop it here: v8.github.io/tools/head/hea…

Thought that EC2 to host my website was a safe choice Seeing random hickups (1m - 30m) every other day 🤔 My stack: nextjs (PM2) and python (gunicorn). CPU is not a problem (below 20% usually) RAM also not (~50%) Any hints?