Sane, Documented Default Values
Designing values that are safe out of the box.
Sane, Documented Default Values is a free Helm Academy lesson on CoddyKit — lesson 2 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Helm Academy learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Defaults Are the First Impression
Most people install your chart with zero overrides, so the default values in values.yaml decide whether it works on the first try or fails confusingly.
Safe Out of the Box
Aim for defaults that install cleanly on a fresh cluster with no surprises. A new user running helm install with no flags should get a working release.
Document Every Key
Add a comment above each value explaining what it does and its accepted range. values.yaml doubles as your chart's configuration manual.
# Number of pod replicas to run
replicaCount: 1Prefer Flat, Predictable Keys
Group related settings under clear parent keys like image or resources. A predictable structure makes overrides easy to write and review.
image:
repository: nginx
tag: "1.27"
pullPolicy: IfNotPresentConservative Resource Defaults
Ship modest resource requests so the chart fits small clusters, but leave limits commented or empty so users can tune for their own workloads.
Booleans for Optional Features
Gate optional resources like an Ingress behind an enabled flag. Default it off so basic installs stay minimal and predictable.
ingress:
enabled: falseAvoid Required Inputs When You Can
Use the required function only for values that truly cannot have a sensible default, like a domain. Fewer mandatory inputs means a smoother first install.
{{ required "ingress.host is required" .Values.ingress.host }}Type Consistency
Keep each value's type stable. If tag is a string, always quote it so 1.27 is not parsed as a number and breaks your image reference.
tag: "1.27"Expose, Don't Hardcode
If a user might reasonably change a setting, surface it in values.yaml rather than burying it in a template. Flexibility lives in values.
Show Users the Knobs
Anyone can list every option with helm show values. Well-commented defaults turn that command into instant, accurate documentation.
helm show values ./mychartAdd a Schema for Safety
A values.schema.json file validates user input before rendering, catching typos and wrong types with a clear error instead of a broken manifest. 🛡️
Quick Check
You want an optional Ingress that does not appear unless requested. What is the best default?
Recap
You saw how sane defaults, clear comments, consistent types, and opt-in features make a chart safe and friendly. values.yaml is documentation and config at once. ✅
Frequently asked questions
Is the “Sane, Documented Default Values” lesson free?
Yes — the full text of “Sane, Documented Default Values” is free to read here on the web, and the Helm Academy course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Helm Academy course, upgrade to CoddyKit PRO.
What will I learn in “Sane, Documented Default Values”?
Designing values that are safe out of the box. You practise Helm Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Helm Academy?
No prior experience is required. Helm Academy on CoddyKit is structured for beginners through advanced learners; this is — lesson 2 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “Sane, Documented Default Values” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Helm Academy lesson?
Yes. Every Helm Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- Standard Labels and Naming Conventions
- Sane, Documented Default Values
- Hardening Pods with securityContext
- Pinning Versions and Avoiding latest