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Writerside/topics/Base-Path.md

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+# Base Path
+
+Unfortunately you need to build the docker container, to configure a url base path. This is because
+SvelteKit needs to know the base path at build time.
+
+## Docker Build Arguments
+
+When building the Docker image for the frontend, you can pass build arguments to set the base path and version.
+
+### `BASE_PATH`
+
+Sets the base url path, it must begin with a slash and not end with one. Example (in build command):
+- clone the repo
+- cd into the repo's root directory
+- `docker build --build-arg BASE_URL=/media -f Dockerfile .`
+
+### `VERSION`
+
+Sets the version variable in the container. This isn't strictly necessary, but it can be useful for debugging or versioning purposes.
+Example: `docker build --build-arg VERSION=locally-built -f web/Dockerfile .`