# Integrations
| environment variable | default | example | description |
|------------------------|---------|-------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------|
| `HD_PLANTUML_SERVER` | - | `https://www.plantuml.com/plantuml` | The PlantUML server that HedgeDoc uses to render PlantUML diagrams. If this is not configured, PlantUML diagrams won't be rendered. |
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| `HD_IMAGE_PROXY` | - | `https://image-proxy.example.com` | **ToDo:** Add description |
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