AWS Certified AI Practitioner (AIF-C01) — Exam Notes

Exam code AIF-C01 . Foundational level. 65 questions total: 50 scored, 15 unscored (you cannot tell which is which). Passing score is 700 / 1000 . No penalty for guessing. Duration: 90 minutes. Cost: $100. Question types include multiple choice, multiple response (select all correct answers), ordering, and matching. The newer ordering and matching types are unique to this exam at foundational level — read them carefully before answering. 20% 24% 28% ←… Read More

Explained: Exploratory Data Analysis

Someone drops a CSV in your lap. Maybe it's a database export, a log dump, or a spreadsheet that's been passed around for two years with no documentation. Your job is to do something useful with it. Where do you even start? Most engineers' instinct is to jump straight in: write a query, train a model, build a chart. That instinct is wrong, and it will cost you. You'll spend hours chasing a correlation that turns out to be an artif… Read More

Architecture: AWS Fargate

You have a containerized service. You want it running in AWS. You create an ECS cluster, write a task definition, and hit deploy. A minute later, your container is up and serving traffic. You never touched a server. That convenience hides a remarkable amount of engineering. Somewhere in AWS, a scheduler decided where your task would run, a microVM was created and booted in milliseconds, a network interface was injected into your VPC, and your con… Read More

Explained: Chaos Engineering

It's 2 a.m. Your on-call phone goes off. A payment service is down, and nobody can explain why. It worked fine in staging. It passed every test. But somewhere in the tangle of microservices, a database connection pool quietly exhausted itself, and the fallback that was supposed to kick in never did. Nobody knew the fallback was broken. It had never been tested in production. Not once. This is the failure mode that chaos engineering was built … Read More