Three Helm Config Mistakes That Caused Outages and a Security Breach

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A DevOps team managing 15 microservices across staging and production with Helm and ArgoCD encountered three critical failures stemming from poor values-file practices. The first issue was treating environment override files as full config copies rather than minimal diffs, which caused a silent three-week config drift that led to a production timeout outage. The second mistake involved copy-pasting identical resource requests across all services without environment-aware tuning, resulting in roughly $400 per month in wasted staging spend and an OOMKill of a payment service during a traffic spike. A third lapse saw secrets accidentally committed directly into a Helm values file in Git, creating a security exposure. The team concluded that 'it's just YAML' thinking breaks down at scale when multiple engineers share config files without a common understanding of Helm's deep-merge behavior.

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