The lifecycle and the toolchain
Summary: the DevOps lifecycle is often represented as an infinite loop in eight phases. This lesson details each phase, presents the landscape of corresponding tools, and above all gives the learning order that avoids the most common mistake: starting with Kubernetes.
1. The cycle in eight phases
What the loop shape means, and it is not decorative: phase 8 feeds phase 1. What you observe in production determines what you will build next. An organization where monitoring never influences the roadmap has a linear chain, not a cycle — and it keeps building according to assumptions it never verifies.
2. The tool landscape
An important point about the length of this list: nobody masters all of it. Job offers often list fifteen technologies; in practice, a team really uses five or six. Do not let these lists discourage you — they describe a wish, not a requirement.
Two skills are truly non-negotiable: Linux and Git. Everything else depends on the company's context.
3. The recommended learning order
The most common learning mistake: starting with Kubernetes. It is understandable — it is the most visible word in job offers. But Kubernetes assumes an understanding of Linux, containers, networking, storage and certificates. Without these foundations, you copy YAML files without understanding, and you are unable to diagnose the first real problem.
Step 3 is the one people skip and shouldn't. Many people learn tools without ever learning to program. Yet DevOps consists of automating, and automating means writing code. Someone who can write a decent Python script is more useful than someone who knows the names of twenty tools.
The advice for step 6: choose a single cloud provider and go deep. The concepts transfer 80% from one provider to another. Three superficial certifications are worth less than one real skill.
4. Our discovery courses, by lifecycle phase
| Lifecycle phase | Corresponding discovery course |
|---|---|
| Code | Git — the concepts then Git in practice |
| Build | Docker |
| Test and release | CI/CD |
| Deploy | Kubernetes |
| Operate | Linux, Ansible |
| Provision | Terraform, cloud |
| Monitor | Observability |
| Cross-cutting | DevSecOps |
Each discovery course explains the why; the corresponding Premium course teaches the how with hands-on exercises.
5. Infrastructure as Code — the key notion
The benefit least mentioned and most important: peer review. When an infrastructure change goes through a merge proposal reviewed by a colleague, you eliminate a large share of the configuration errors — the ones that expose storage publicly or open a port to the entire internet. A click in a web console is never reviewed by anyone.
See our Terraform and Ansible courses.
6. GitOps — the recent evolution
Benefit 2 is the one that most appeals to operations teams. The classic problem is well known: someone changes a setting by hand during an incident, does not document it, and six months later nobody understands why production differs from the code. With GitOps, that manual change is automatically reverted — which forces going through Git, and therefore leaving a trace.
7. How to avoid choosing the wrong tools
Rule 1 is the most frequently broken, out of a desire to learn. Kubernetes is fascinating, but for an application deployed on one or two servers, it adds considerable complexity for no benefit. The right tool depends on your scale, not on what is fashionable.
An honest nuance, however: if your goal is to learn for your career, setting up a Kubernetes cluster on a personal project is an excellent investment. The simplicity advice applies to professional decisions, not to your learning.
Remember in 30 seconds
- Eight phases: plan, code, build, test, release, deploy, operate, monitor. Phase 8 feeds phase 1 — it is a cycle, not a chain.
- Nobody masters every tool. Job offers describe a wish, not a requirement.
- Two non-negotiable skills: Linux and Git.
- Learning order: Linux → Git → a scripting language → Docker → CI/CD → one cloud → Terraform → Kubernetes last.
- The most common mistake: starting with Kubernetes. Without the foundations, you copy YAML without understanding.
- Do not forget to learn to program. Automating means writing code.
- One cloud provider in depth is better than three superficially — the concepts transfer 80%.
- Infrastructure as Code: reproducible, traceable, peer-reviewable, and the code serves as documentation.
- GitOps: Git is the source of truth, the operator pulls changes. End of configuration drift.
- Choose the simplest thing that solves your problem. Kubernetes for three containers is a bad professional choice — but a good learning project.