Tim Kadlec

Principal Product Manager @Cloudflare—focused on perf & observability.

Co-chair of @perfnowconf.

Taller than my photo looks.

[Tim Kadlec @tkadlec]

@DrizzleORM What page is it taking you to?

[Tim Kadlec @tkadlec]

@DrizzleORM That being said, we're working on giving users a LOT more visibility and power here. What would your dream scenario be here to see next?

[Tim Kadlec @tkadlec]

@DrizzleORM It _should_ be taking you directly to your analytics filtered to those response codes (ex: clicking 4xx takes you to a page filtered to only the requests that triggered 4xx, clicking 5xx takes you to a page filtered only to requests that triggered 5xx)

[Tim Kadlec @tkadlec]

@Dan_The_Goodman well that seems excessive

wanna DM me some details and I can dig in?

[WebExpo Conference - May 27-29, 2026 @webexpo]

Is “fast” fast enough? 🚀 @tkadlec explores why today’s performance benchmarks won’t cut it tomorrow at #WebExpo.
Learn how new web standards push performance and how to stay ahead TODAY.
Don't fall behind and join us in Prague, May 28–30!
https://t.co/AdIjiFw62P

[Tim Kadlec @tkadlec]

@csswizardry @AmierOSaleh I like thoughts.

[Tim Kadlec @tkadlec]

@marshnet_social @shauncooley @moguls28off @eastdakota @Cloudflare 👀

[Tammy Everts @tameverts]

Is TTFB a hot new metric? No.

Is it a key #webperf metric for tracking responsiveness? YES! Slow TTFB virtually guarantees your site will deliver a poor #UX. Bonus: It's widely available across browsers!

@tkadlec explains how to diagnose TTFB issues...

https://t.co/8ekiAS219z

[Tammy Everts @tameverts]

Exciting new product updates from our awesome dev team!

Long story short: We've made it easier and faster for you to find and fix the issues that are hurting your Vitals metrics!

#webperf #corewebvitals #ux

[Tim Kadlec @tkadlec]

@philhawksworth 😂

nope

[SpeedCurve @SpeedCurve]

Hello #SmashingConf NY folks! Be sure to sign up for this FREE lunch session with Tim Kadlec (@tkadlec).

Tim will give a tour of new #webperf metrics + how to use them to home in on which optimizations will make your pages faster (and which ones won't).

https://t.co/yDQBcTeXCG

[Tim Kadlec @tkadlec]

@AWSSupport Got a ticket open

[Tim Kadlec @tkadlec]

Err...this is gonna sound crazy, but I'm pretty sure AWS is...randomly deleting dynamoDB items?

My app has one & only one point where it deletes items and I can see no record in CloudTrail of anything being deleted, yet every day a couple random items just...aren't there anymore

[Tim Kadlec @tkadlec]

@oferbel No...that's what I thought too, but nothing there.

[Tim Kadlec @tkadlec]

me anytime I try to figure out how to accomplish anything in the AWS UI

[Tim Kadlec @tkadlec]

ok hold up how long has this been there without me noticing

chrome drawing a red line between style recalc and the method that triggered it in their flame charts

[SpeedCurve @SpeedCurve]

NEW: Our latest release includes RUM attribution and subparts for INP! @cliffcrocker explains:

🟡 Element attribution
🟢 Where time is spent within INP, leveraging subparts
🔴 How to use this information to fix INP issues

https://t.co/EWAXiNIZ30 #corewebvitals #webperf #ux

[Tim Kadlec @tkadlec]

👀

[Tammy Everts @tameverts]

Keeping your site fast is a crucial endless game. Yet it's perilously easy to lose focus. @tkadlec uses the analogy of guardrails (automated testing & alerts) and breadcrumbs (deployment tracking) to make #webperf more visible throughout the dev process.

https://t.co/fF1dtEByCd

[SpeedCurve @SpeedCurve]

NEW! Based on your feedback, we've expanded your capabilities for on-demand testing! This how-to post covers:

🟡 Scheduled vs on-demand tests
🟡 Run on-demand tests for site or custom URL
🟡 View & compare test details
🟡 Group tests as a deploy

https://t.co/mjHwppqaIc #webperf