# Layer

• run(+command): Run a shell command.

command should be a string containing a shell script. At runtime, the script will be executed with /bin/sh -c.

This is equivalent to RUN in Dockerfile.

• copy(+src, +dst): Copy local file/directory.

Existing files already in the image will be overwritten in the new layer, and directories will be copied recursively. Any non-existant parent directories will be created.

This is equivalent to COPY in Dockerfile without a --from option. Following Docker's behavior, if src is a directory, the content of src is copied into dst, but not src itself. This means that copy("dir", "/") basically means cp -r dir/* /.

If dst is a relative path, it is resolved based on the current image's working directory. src must be a relative path, and must not be outside the build context.