diff --git a/website/data/language-nav-data.json b/website/data/language-nav-data.json
index 3efdda766..74310b84b 100644
--- a/website/data/language-nav-data.json
+++ b/website/data/language-nav-data.json
@@ -278,6 +278,10 @@
       {
         "title": "Version Constraints",
         "path": "expressions/version-constraints"
+      },
+      {
+        "title": "Pre and Postconditions",
+        "path": "expressions/preconditions-postconditions"
       }
     ]
   },
diff --git a/website/docs/language/expressions/preconditions-postconditions.html.mdx b/website/docs/language/expressions/preconditions-postconditions.mdx
similarity index 100%
rename from website/docs/language/expressions/preconditions-postconditions.html.mdx
rename to website/docs/language/expressions/preconditions-postconditions.mdx