YAML for DevOps Configuration Course

Lesson 1 • What YAML Is and Why It Matters

Introduces YAML's origin, design philosophy, and role in modern config management. Establishes context for why DevOps teams prefer YAML over XML and JSON.

Lesson 2 • Core Syntax Rules and Structure

Covers indentation, whitespace sensitivity, and document markers. Correct syntax habits prevent the most common parsing errors in pipelines.

Lesson 3 • Validating and Linting YAML Files

Introduces tools and techniques for catching syntax errors before deployment. Validation is the first quality gate in any DevOps workflow.

Lesson 4 • Collections: Mappings and Sequences

Teaches key-value mappings and ordered sequences as YAML's primary data structures. These structures underpin every real-world config file.

Lesson 1 • Anchors and Aliases for Reuse

Defines anchors (&) and aliases (*) to reference repeated data blocks. Reduces duplication and keeps large config files consistent.

Lesson 2 • Merge Keys for Shared Defaults

Explains the << merge key to inherit and override shared mapping defaults. Enables template-like patterns without external tooling.

Lesson 3 • YAML Schema and Tag Customization

Introduces YAML schemas (failsafe, JSON, core) and custom tags for domain-specific types. Enables precise type control in advanced toolchains.

Lesson 4 • Complex Nested Structures

Builds skills for deeply nested mappings and mixed-type sequences. Prepares learners for real infrastructure configs with layered hierarchies.

Lesson 1 • GitLab CI/CD Pipeline Files

Teaches .gitlab-ci.yml structure including stages, scripts, and extends. Covers GitLab-specific features like rules and include directives.

Lesson 2 • CI/CD Pipeline Concepts and YAML Mapping

Maps CI/CD stages, jobs, and steps to YAML structures. Establishes the mental model needed before writing any pipeline file.

Lesson 3 • Pipeline Optimisation Techniques

Covers caching, parallelism, conditional execution, and dependency graphs. Reduces pipeline runtime and resource consumption in production workflows.

Lesson 4 • Writing GitHub Actions Workflows

Covers workflow syntax, job dependencies, and reusable actions in GitHub Actions YAML. Produces working CI workflows for code repositories.

Lesson 1 • Namespaces, RBAC, and Resource Quotas

Defines multi-tenancy controls using YAML-based namespace and RBAC objects. Enforces least-privilege access and resource boundaries.

Lesson 2 • Services, ConfigMaps, and Secrets

Teaches networking and configuration injection objects in YAML. Decouples app config from container images for portability.

Lesson 3 • Kubernetes Resource Model and YAML

Explains apiVersion, kind, metadata, and spec as the universal manifest skeleton. Every Kubernetes object follows this four-field pattern.

Lesson 4 • Helm Charts and YAML Templating

Introduces Helm as a YAML templating layer over raw Kubernetes manifests. Enables parameterised, reusable application packaging.

Lesson 1 • IaC Principles and YAML's Role

Explains declarative vs. imperative IaC and where YAML fits in the toolchain. Sets the foundation for tool-specific chapters that follow.

Lesson 2 • Drift Detection and Config Reconciliation

Explains how IaC tools detect and correct drift between desired and actual state. Ensures YAML configs remain the authoritative source of truth.

Lesson 3 • AWS CloudFormation Templates

Teaches CloudFormation YAML template sections for provisioning AWS resources. Covers parameters, resources, and outputs for reusable stacks.

Lesson 4 • Pulumi and YAML-Based IaC

Introduces Pulumi's YAML provider for defining cloud resources without a programming language. Broadens learners' IaC tool awareness.

Lesson 1 • Kubernetes Manifest Validation Tools

Introduces kubeval, kubeconform, and kube-score for Kubernetes-specific YAML checks. Catches API deprecations and best-practice violations early.

Lesson 2 • Custom Validation Rules and Policies

Covers writing custom rules with tools like Conftest and OPA for policy-as-code. Enforces organisational standards beyond basic schema checks.

Lesson 3 • Automated YAML Testing in Pipelines

Integrates schema and policy checks into CI pipelines as automated gates. Prevents invalid configs from reaching staging or production environments.

Lesson 4 • Documentation and Style Guides for YAML

Establishes team-wide YAML style conventions and inline documentation practices. Consistent style reduces review friction and onboarding time.

Lesson 1 • Kustomize for Environment Overlays

Uses Kustomize kustomization.yaml to manage base and overlay configs per environment. Eliminates environment-specific file duplication.

Lesson 2 • GitOps Principles and YAML Alignment

Defines the four GitOps principles and explains how YAML manifests fulfil them. Establishes the conceptual foundation before tool configuration.

Lesson 3 • Flux CD Kustomization and Sources

Teaches Flux GitRepository, Kustomization, and HelmRelease YAML resources. Flux's toolkit approach offers fine-grained GitOps control.

Lesson 4 • Progressive Delivery with YAML

Introduces canary and blue-green deployments configured via YAML in Argo Rollouts. Reduces deployment risk through incremental traffic shifting.

Lesson 1 • Least-Privilege YAML Configuration

Applies least-privilege principles to Kubernetes RBAC, pod security, and network policies. Reduces blast radius of misconfigured or compromised workloads.

Lesson 2 • YAML Injection and Parsing Attacks

Explains YAML deserialisation vulnerabilities and injection vectors in dynamic configs. Awareness of these risks is essential for secure pipeline design.

Lesson 3 • Secrets Management in YAML Workflows

Covers safe patterns for injecting secrets into YAML-driven systems without hardcoding. Prevents credential leaks in version-controlled files.

Lesson 4 • YAML at Scale: Modularisation Strategies

Teaches splitting large configs into composable modules using includes, overlays, and generators. Manages complexity in enterprise-scale YAML repositories.