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Build a Manual with Starlight #3: Writing Content — Code Blocks, Mermaid, asides
We cover three elements that make docs pleasant to read: code blocks that carry titles and line highlights, Mermaid diagrams added via a plugin, and asides that show cautions and warnings. We go over how to use each in Starlight.
Certified Kubernetes Administrator (CKA) #26: Exam Tips, Time Management, and Patterns People Miss
A condensed cheat sheet to read one more time right before you sit the CKA hands-on exam. We pull together time management for running roughly 15–20 tasks in 2 hours, the priority order driven by points and troubleshooting, a refreshed kubectl speed setup, context switching across multiple clusters, using the official docs, the recurring patterns where operators bleed points and how to avoid them, easily confused concept pairs, and a pre-exam checklist for each of the five domains. Next up in #27 is a full-scale hands-on mock exam.
Certified Kubernetes Application Developer (CKAD) #21 Full-Length Practice Exam — 18 Tasks with Solutions
The final post of the Certified Kubernetes Application Developer (CKAD) series. Work through 18 task scenarios that integrate every domain in the same flow as the real exam, then unfold each task's solution commands, YAML, and explanation to grade yourself. Check your weak domains against the 66% pass line and lay out a review path.
Certified Kubernetes Security Specialist (CKS) #19: Exam tips, time management, and patterns people get wrong
A condensed read to go through one more time right before you sit the CKS hands-on exam. We cover the time management of running roughly 15–20 tasks in 2 hours, prioritizing tasks by tool, re-running the setup right after the exam starts, switching context across multiple clusters, making use of kubernetes.io/docs and the Falco, Trivy, AppArmor, and gVisor official docs, the recurring patterns that leak points on a security hands-on exam and how to avoid them, easily confused concept pairs, and a per-domain pre-exam checklist across all six domains. Next up, #20 is a full-scale hands-on mock exam.
Hardware Intermediate #3: Memory Deep Dive — available, Dirty Pages, Container Limits
The one column that matters in free output, the dirty-page behavior behind sudden write bursts, what swappiness really means, and cgroup memory limits with container OOMKilled — memory as you meet it in operations.
How Are YouTube and Netflix Recommendations Decided? An Introduction to Recommender Systems
This post explains, without any code, how YouTube's next video and Netflix's home screen get tuned to your taste. It covers collaborative filtering that follows similar people, the content-based approach that looks at similarity between items, and limits like the filter bubble, at a non-developer's level.
How Does Find My Locate a Phone That's Turned Off? The Offline Finding Network
A phone with no internet and no power still shows up on the map. The secret is the Find My network, which turns hundreds of millions of strangers' devices into anonymous relays. This post covers Bluetooth signals, end-to-end encryption, AirTag, and anti-stalking protections.
React State Management in Depth #2: Server State with TanStack Query
Move the data fetching you wrote with useEffect and useState over to TanStack Query, and caching, refetching, and loading and error handling all come for free. A walkthrough of the core of useQuery and useMutation.
Red Hat Certified Engineer (RHCE) #18: Exam Tips and Time Management
A condensed cheat sheet to read once more right before walking into the RHCE (EX294) hands-on exam. We cover the operating strategy for auto-configuring systems with playbooks over four hours and the habit of piling up tasks, running `--syntax-check` and `--check` often, solving unknown modules with ansible-doc and the system roles example docs in an offline environment, verifying idempotency with two runs, the recurring patterns that bleed points and the easily confused concept pairs, and a per-domain checklist for the moment before you sit. The next post, #19, is a full-scale mock exam.
Red Hat Certified System Administrator (RHCSA) #15: Exam tips, time management, and patterns people get wrong
A compressed read for the moment right before you walk into the RHCSA hands-on exam. We cover the time management that runs your 2.5 hours from the easy tasks outward in dependency order, how to solve unfamiliar tasks with man pages when there is no internet, the habit of verifying tasks with a reboot, the recurring patterns that bleed points across the whole series (fstab typos, missing service enable, missing firewall reload, missing persistent SELinux settings) and how to avoid them, easily confused concept pairs, and a domain-by-domain checklist to run right before you sit. The next post, #16, is a full-scale mock exam.
Why Ads Follow You: Cookies, RTB, and Privacy
Why the running shoes you glanced at follow you across every news site — explained without code. What ad networks collect through cookies and device IDs, how the 0.2-second real-time bidding auction works, and what users can still do as third-party cookies fade and Apple ATT changes the rules.
LLM App Development #7: Embeddings and Vector Search
Embeddings turn text into vectors that carry meaning, and vector search finds similar documents using those vectors. The preparation step for RAG in the next part.