Configuring Subcharts from Parent Values
Passing values down by subchart name.
Configuring Subcharts from Parent Values is a free Helm Academy lesson on CoddyKit — lesson 3 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.
Subcharts Have Their Own Values
Each subchart ships its own values.yaml with its own defaults. From your parent chart you can reach in and override those settings.
Nest Under the Subchart Name
To configure a subchart, add a key in your parent values.yaml matching its name. Everything under that key flows into the subchart.
postgresql:
auth:
username: appuser
database: appdbThe Key Matches name or alias
The parent key must equal the subchart's name from Chart.yaml, or its alias if you set one. A typo silently configures nothing.
Parent Overrides Subchart Defaults
Values you set in the parent take precedence over the subchart's own defaults. The subchart still fills in anything you leave unset.
Override on the CLI Too
You can drive subchart values from the command line with --set, using the same dotted, subchart-prefixed path.
helm install web ./mychart \
--set postgresql.auth.username=appuserMatch the Subchart's Schema
Your nested keys must mirror the subchart's actual values structure. Run helm show values on the subchart to learn the exact paths.
helm show values bitnami/postgresqlConfirm With a Render
Use helm template to render the parent and check the subchart picked up your overrides before you touch a real cluster.
helm template web ./mychart | grep -A3 postgresqlSubcharts Cannot See Parent Keys
A subchart only reads values under its own key, not your parent's top-level fields. To share data across charts you need global values.
Alias Means Alias Key
If you gave a dependency an alias, configure it under that alias. The same chart added twice gets two separate value blocks.
primary-db:
auth:
database: orders
replica-db:
auth:
database: orders-roDocument the Knobs You Expose
Comment the subchart keys in your parent values.yaml. It saves users from digging through the subchart's full schema themselves.
Keep Overrides Minimal
Only override what you must. Leaning on sensible subchart defaults keeps your parent values short and easier to maintain over time.
Quick Check
Your chart depends on a subchart named redis. Where do you set its password?
Recap: Configuring Subcharts
You learned to override subchart settings by nesting them under the subchart's name or alias in parent values, then verifying with a render. 🎛️
Frequently asked questions
Is the “Configuring Subcharts from Parent Values” lesson free?
Yes — the full text of “Configuring Subcharts from Parent 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 “Configuring Subcharts from Parent Values”?
Passing values down by subchart name. 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 3 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “Configuring Subcharts from Parent 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
- Declaring Dependencies in Chart.yaml
- Vendoring with helm dependency update
- Configuring Subcharts from Parent Values
- Conditions, Tags, and Global Values