Practical insights for IT professionals
Engineering • DevOps • Cloud
Serhii Matiushchenko 
Reading Time: 6 minutesA simple timestamp update triggered a hidden rolling restart, created contention for memory and disk I/O, and temporarily made production unavailable. This incident shows how a metadata operation can become a control-plane command and why adding resources does not address the underlying design flaw.
Reading Time: < 1 minuteAITEX invited me to the judging panel for Summer 2026. The summit ran online on 30–31 August. I turned in the scores after the event. The certificate arrived as soon as the work was in.
Reading Time: < 1 minuteInvited to judge HackOnVibe, 13–16 August 2026. Twelve teams. The brief: practical code for promoting a new mobile app — a deep link, an SDK, a referral — not a description of an idea.
Reading Time: 4 minutesWhen AWS announced the retirement of the old ec2messages endpoint, it turned out the problem wasn’t just an outdated SSM Agent. This is a story about inherited infrastructure: a 2017 IAM policy that still showed green in the console, and a Terraform module that, if updated the “proper” way, threatened to destroy the storage volumes of a live production cluster. Sometimes the most honest choice is to deliberately leave technical debt in place — rather than force the correct fix and risk breaking everything.
Reading Time: < 1 minuteBefore the hackathon begins, please read the topic and obtain your personal GitHub repository for development. More details are available here: HackOnVibe.com Certificates of participation will be awarded to everyone. Winners will receive certificates (example: certificate). Esteemed judges from the US, including representatives from Big Tech companies like Salesforce, will provide valuable feedback and networking … Read more
Reading Time: 2 minutesDuring a least-privilege cleanup I discovered that a workload we believed was using IRSA had actually been running on the node IAM role for almost a year. Here’s how it was found and what changed in my verification process.
Reading Time: 6 minutesWe built a watchdog to automatically reload nginx whenever it started timing out against an AWS ALB — the classic “cached a stale IP” problem. It worked… until a different domain on the same box went down for hours while the script sat there happily reporting that everything was fine. This is the story of how a monitoring gap, a partial deploy, and a threshold tuned for the wrong failure shape turned a good idea into false confidence — and what it took to fix the class of problem instead of just the one instance that had already bitten us.
Reading Time: 3 minutesBlocking an attacker’s IP address stopped nothing, because the address hitting the edge was never the attacker’s own. The same flood kept coming back seconds later from a brand-new address, one hop further back than the block was looking.
Reading Time: 3 minutesA one-line module version bump, meant to carry over a small permissions fix, produced a plan that wanted to destroy and rebuild the storage volumes of a live cluster. The resource hadn’t changed at all; the way the tool addressed it internally had.
Reading Time: 3 minutesA routine rolling node replacement turned into a lesson in credential archaeology, with three plausible SSH keys and only one of them actually working, none of the mismatch visible until someone tried to connect under a maintenance-window clock.