diff --git a/.github/workflows/site.yml b/.github/workflows/site.yml
index bf2efb9..79c39ca 100644
--- a/.github/workflows/site.yml
+++ b/.github/workflows/site.yml
@@ -21,6 +21,6 @@ jobs:
           path: .cache
           restore-keys: |
             mkdocs-material-
-      - run: pip install mkdocs-material
+      - run: pip install mkdocs-material plantuml-markdown
       - name: Deploy site
         run: mkdocs gh-deploy --force
diff --git a/docs/Developer/ProposalDM.md b/docs/Developer/ProposalDM.md
new file mode 100644
index 0000000..8b1015b
--- /dev/null
+++ b/docs/Developer/ProposalDM.md
@@ -0,0 +1,3 @@
+# ProposalDM
+
+The underlying proposal data model is defined in a [separate project](https://ivoa.github.io/ProposalDM/).
\ No newline at end of file
diff --git a/docs/Developer/api.md b/docs/Developer/api.md
index 5ecca52..b55663a 100644
--- a/docs/Developer/api.md
+++ b/docs/Developer/api.md
@@ -1,8 +1,4 @@
-+++
-title = "Polaris REST API"
-type = "swagger"
-weight = 1
-description = "Reference for the Polaris API"
-+++
+# API
+
+A swagger Ui for the deployed api is available at https://kilburn.jb.man.ac.uk/pst/api/q/swagger-ui/
 
-{{< swaggerui src="../../../openapi/openapi.yaml" >}}
diff --git a/mkdocs.yml b/mkdocs.yml
index 2a2e60e..a2f15e4 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -21,6 +21,7 @@ nav:
       - Reference:
           - Use Cases: Developer/use-cases.md
           - Architecture: Developer/architecture.md
+          - Data Model: Developer/ProposalDM.md
           - API: Developer/api.md
       - Deployment:
           - Getting Started: Deployment/index.md
@@ -39,9 +40,8 @@ theme:
 markdown_extensions:
   - tables
   - footnotes
-# TODO add this once https://github.com/mikitex70/plantuml-markdown/pull/94 has been done
-#  - plantuml_markdown:
-#      server: https://www.plantuml.com/plantuml  # PlantUML server, for remote rendering
+  - plantuml_markdown:
+      server: https://www.plantuml.com/plantuml  # PlantUML server, for remote rendering
   - pymdownx.superfences:
       custom_fences:
         - name: mermaid