ArgoCD: Deploy with confidence, conquer YAML mysteries

A session from LINE THAILAND DEVELOPER CONFERENCE 2025 by Neutron Soutmun, Senior SRE at LINE Thailand

1. ArgoCD: Deploy with confidence, conquer YAML mysteries Neutron Soutmun / Senior SRE / LINE Thailand
2. • Senior SRE LINE Company (Thailand) Season 7 • Debian Developer Debian Community Season 10 About Me pub rsa4096 2009-05-10 F532 DA10 E563 EE84 4409 77A1 9D04 70BD A6CD C457 GPG
4. • Technical Debt the roots of all fears • GitOps reduces technical debt • ArgoCD heavy-duty GitOps Agent • Deploy with confidence • Conquer YAML mysteries Agenda
5. Technical Debt The roots of all fears Reckless Prudent Deliberate Inadvertent We don’t have time We don’t know how We will deal with it later We should not have done this Rushed Development Inexperience Poor Design or Coding Standards Insufficient Maintenance Security Risks System Instability Developer Frustration Missed Opportunities Reduced Productivity Increased Costs
6. GitOps reduces technical debt
7. OpenGitOps Principles v1.0.0 Declarative Versioned and Immutable Pulled Automatically Continuously Reconciled Git Ops
8. Declarative Configuration YAML
9. Versioned and Immutable 0.2536.10 https://github.com/line/headver Head Semantic Version compatible HeadVer YearWeek Build
10. Git version control - simple but powerful Create PR Peer Review Merge Revert Review Request Approved
11. OpenGitOps Principles v1.0.0 Declarative Versioned and Immutable Pulled Automatically Continuously Reconciled Git Ops Pulled Automatically Manually Continuously Manually Reconciled
12. ArgoCD heavy-duty GitOps Agent
13. Non-Stop Reconcile 40,000+ hours in 5 years
14. Deploy with confidence Need More
15. Continuous Integration GitHub Actions
16. ArgoCD Diff Preview a tool that renders the diff between two branches in a Git repository https://github.com/dag-andersen/argocd-diff-preview
17. Happy Hacking!
18. Fail Early fail fast, fail often
19. Dehydrated Configuration what you see is not what you get
20. Are you confident? Murphy’s Law: Anything that can go wrong will go wrong
21. Conquer YAML mysteries There’s no magic
22. . YAML common errors ⎯ Indentation • Inconsistent • Incorrect Levels ⎯ Syntax and Formatting • Missing Colons • Unquoted Strings with Special Characters ⎯ Data Structure • Incorrect List Formatting • Improper Use of Anchors and Aliases ⎯ Other • Typos • Encoding Issues shoot yourself in the foot apiVersion: apps/v1 Kind: Deployment medatadata: name: example spec: replicas: "2" selector: matchLabels: app.kubernetes.io/name: example template: metadata: labels: app.kubernetes.io/name: example spec: containers: * name helloworld image: debian:trixie command: - sh - -c - "sleep infinity"
23. JSON Schema. Let IDE do their job • JSON Schema Store https://www.schemastore.org • JSON Schemas for every version of every object in every version of Kubernetes https://github.com/yannh/kubernetes-json-schema • Popular Kubernetes CRDs (CustomResourceDefinition) in JSON schema format https://github.com/datreeio/CRDs-catalog YAML Language Server (LSP) + Syntax Highlighting https://github.com/redhat-developer/yaml-language-server
24. AI is your colleague AI Assisted + Vibe Coding
25. YAML Formatter • yamlfmt https:// github.com/google/yamlfmt • dprint https://dprint.dev Team agreement on code formatting Enforce consistent code style, improving collaboration and code quality Before After
26. Kubernetes YAML linter • kubeconform https:// github.com/yannh/kubeconform Linter save the day valuable in development workflows
28. Pre then Post Deploy Feedback https://github.com/pyrra-dev/pyrra SLI/SLO + Error Budgets Service Level Indicator Service Level Objective
30. Increase Reliability More Confident Reduce Failures • Reduce technical debt • Continuous Deployment • Good shape configuration • Simulation/Dry-Run • Errors detection • Good post-deploy feedback Summary SRE Focus
31. We are hiring! LGTM https://careers.linecorp.com/jobs/2835/