# Where does kustomize build print warnings about deprecated fields such as patchesStrategicMerge?

Kustomize, Easy (Beginner), Concepts. https://k8wiz.com/uquiz/where-does-kustomize-build-print-warnings-about-deprecated-fields-such-as-patchesstrategicmerge

- A. To stderr, separate from the YAML on stdout
- B. As YAML comments at the top of the stdout output
- C. Into a kustomize-warnings.log file in the directory
- D. Nowhere unless you pass the --enable-warnings flag

**Answer:** To stderr, separate from the YAML on stdout

**Explanation:** Kustomize writes each deprecation warning to stderr, so piping kustomize build into kubectl apply -f - keeps working. The messages start with # Warning:, which makes them look like YAML comments, but they never reach the output stream.