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Hardware Intermediate #9: Hands-On: Diagnosing a Slow Server — Series Finale
A diagnostic walkthrough that starts from a "the service is slow" report and narrows down through the four resources one by one. Define the symptom, check each resource, confirm the hypothesis, apply a fix, and re-measure. We close the Hardware Intermediate series with the principles of tuning.
How Do Google Translate and DeepL Work? Three Generations of Machine Translation
Point your phone camera at a foreign menu and the words change into your language right on the screen. How Google Translate and DeepL pull this off — the rule-based, statistical, and neural generations of machine translation, what camera and voice translation really are, and why translators still get things wrong, explained for non-developers.
LLM App Development #13: A Real-World Project — Internal Document Q&A Bot
Bring all the pieces together and build a Q&A bot that answers from internal documents, start to finish. A finale combining RAG, streaming, grounding prompts, and conversation memory.
Gin Basics #3 Request Binding and Validation
Binding request bodies into structs, and validating input with validator tags.
Hardware Intermediate #8: GPUs and Accelerators — The Fifth Resource of the AI Era
The bottleneck of AI workloads often lies beyond the four resources. How a GPU works differently from a CPU, the VRAM and HBM that determine model capacity, reading nvidia-smi, and sharing a GPU with passthrough, vGPU, and MIG — all from an operator's perspective.
Where Do Those 6-Digit Codes Come From? OTP and Two-Factor Authentication Explained
The 6-digit code your authenticator app refreshes every 30 seconds is the result of feeding a shared secret key and the current time into the same calculation on both your phone and the server. What two-factor authentication actually blocks, what scanning that QR code really does, why it works without internet, how it beats SMS codes, and why backup codes matter — explained for non-developers.
LLM App Development #12: Cost, Evaluation, and Observability
What you need to actually operate the app you built. Cutting token cost and prompt caching, evaluation that measures quality, and observability that looks into behavior.
AWS Certified CloudOps Engineer - Associate (SOA-C03) #15 Full-Scale Multiple-Choice Mock Exam — 50 Questions + Explanations
The final post of the SOA-C03 series. Matched to the real exam's domain weights (monitoring 22% , reliability 22% , deployment automation 22% , networking 18% , security 16%), you solve 50 questions and find your weak domains through each question's answer and explanation. Solve them on the clock, then go back to the relevant domain post to shore up any gaps.
Gin Basics #2 Routing and Handlers
How to read path parameters and query strings, and how to group endpoints with router groups.
Hardware Intermediate #7: Storage Networking — iSCSI, FC, NVMe-oF, Multipath
Once the disk leaves the server, storage becomes a network problem. The trade-offs between iSCSI and FC, NVMe-oF for the NVMe era, multipath operations that take charge of path redundancy, and the connection to cloud block storage.
How Do Apple Pay and Samsung Pay Actually Work? NFC and Tokenization Explained
You tap your phone on a store terminal and the payment is done in a second. In that brief moment, NFC exchanges signals and a device-specific token crosses over instead of your real card number. Why your phone never stores your card number, what Samsung Pay's MST was, and what happens when you lose your phone, explained for non-developers.
React State Management in Depth #6: Which Tool, When — a Decision Guide
A single decision flow tying together the built-in tools, TanStack Query, Zustand, Jotai, and Redux Toolkit. The series wrap-up: what to reach for in which situation, and the common traps.