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YAML Anchors, Aliases, and Merge Keys/Merge shared mappings

Combine a base config with environment-specific overrides.

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Section: Anchors and aliases

Merge shared mappings

yaml
yaml
base: &base
  image: node:20
  pullPolicy: IfNotPresent

prod:
  <<: *base
  replicas: 3
Explanation

The merge key `<<` is widely used in tooling that supports YAML merge semantics.

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