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AWS Certified Cloud Practitioner (CLF-C02) #1: Exam Introduction — Structure and Study Strategy
10 min read

AWS Certified Cloud Practitioner (CLF-C02) #1: Exam Introduction — Structure and Study Strategy

The opening post of the AWS Certified Cloud Practitioner (CLF-C02) series. The shape of 65 questions, 90 minutes, and a 700 passing score; the weight and meaning of the four domains; registration and the testing environment; and the study strategy that turns the hands-on feel from the [AWS track](/en/posts/aws-basics-1) into exam answers. This 10-part series targets a CLF-C02 pass, wrapping up with a full-scale mock exam in #10.

Django Advanced #6: Django Channels — WebSocket
8 min read

Django Advanced #6: Django Channels — WebSocket

Channels setup, AsyncWebsocketConsumer, broadcast via channel_layer, push from HTTP views, daphne/uvicorn deployment, nginx WebSocket proxy.

K8s Advanced #3: Admission Controller — OPA Gatekeeper / Kyverno
10 min read

K8s Advanced #3: Admission Controller — OPA Gatekeeper / Kyverno

The K8s API server has a stage that can inspect and mutate manifests right before they're stored in etcd. This stage, called Admission Controller, is the entry point for the operational cluster's policy engine. Policies like "reject containers without limits," "force specific labels," "restrict image origins" are blocked at the manifest level without changing a line of code. This post organizes the position of the admission stage, built-in controllers, ValidatingWebhook and MutatingWebhook, and the models of two policy engines OPA Gatekeeper and Kyverno — all in one cycle.

Modern Python FastAPI #1 Getting Started and Setup
7 min read

Modern Python FastAPI #1 Getting Started and Setup

Why FastAPI, first project setup with uv, Hello FastAPI, automatic OpenAPI/Swagger UI generation — all in one place.

RHEL Advanced #6: Subscription, Satellite, Insights — Operations Infrastructure
9 min read

RHEL Advanced #6: Subscription, Satellite, Insights — Operations Infrastructure

Three Red Hat operations tools you meet not when running one machine, but when running tens or hundreds. subscription-manager ties a machine to a Red Hat subscription, Satellite is the on-prem unified ops platform for lifecycle, content views, and patch automation, and Insights is the SaaS analytics service for vulnerability, stability, and performance recommendations — all in one cycle.

Testing #1 — Why Test? The Place of Unit, Integration, and E2E
5 min read

Testing #1 — Why Test? The Place of Unit, Integration, and E2E

The first post of the testing track. The meaning of the test pyramid, what unit/integration/E2E each catch and miss, and how the question "where to use which test" ultimately becomes a question of how to allocate your time — this post sets up the picture you need to design that allocation.

TypeScript Advanced #4: Template literal types
3 min read

TypeScript Advanced #4: Template literal types

Tools that compose strings at the type level — the `${...}` pattern, Capitalize/Uppercase built-ins, and real-world patterns for modeling route/event names as types.

Why They Tell You to "Clear Your Cache" — Caching and CDNs
5 min read

Why They Tell You to "Clear Your Cache" — Caching and CDNs

This post explains, without any code, what developers mean when they suggest "clearing the cache" or "a hard refresh." It unpacks how a cache, which keeps frequently used things close by, and a CDN, which scatters copies around the world, speed up the web.

Angular Advanced #5 Intro to NgRx — Store, Action, Reducer, Effect
11 min read

Angular Advanced #5 Intro to NgRx — Store, Action, Reducer, Effect

NgRx — the tool for making state flow explicit in large apps. Maps out the roles of Store/Action/Reducer/Effect in a single diagram, and compares side by side with modern Angular's SignalStore and Component Store.

AWS Advanced #6: Secrets Manager / Parameter Store
9 min read

AWS Advanced #6: Secrets Manager / Parameter Store

How Secrets Manager and SSM Parameter Store differ, automatic rotation, fetching from code (boto3 / caching / Powertools), ECS and Lambda integration, IaC wiring, cost comparison — AWS secret / configuration management.

Django Advanced #5: Signals in depth and post-transaction work
8 min read

Django Advanced #5: Signals in depth and post-transaction work

transaction.on_commit, savepoints, custom signals, mute_signals, Celery integration — every tool you need to use signals safely.

Docker in Practice #6 Cloud Deployment — Fly.io / Railway / ECS — Wrapping the Track
10 min read

Docker in Practice #6 Cloud Deployment — Fly.io / Railway / ECS — Wrapping the Track

The final step — taking the images you built and pushed and putting them on real production. Three options (Fly.io , Railway , ECS Fargate), the fork between them, deployment flows, secret management, healthchecks and zero-downtime, and a recap of all 24 posts in the track.