diff --git a/docs/Build.cs b/docs/Build.cs
index 634ba282..aef33586 100644
--- a/docs/Build.cs
+++ b/docs/Build.cs
@@ -3,6 +3,7 @@ namespace NetVips.Docs
     using System;
     using System.IO;
     using System.Threading.Tasks;
+    using Docfx.Dotnet;
 
     class Build
     {
@@ -13,6 +14,7 @@ static async Task Main(string[] args)
             var currentDirectory = Directory.GetCurrentDirectory();
 
             Directory.SetCurrentDirectory(projectDir);
+            await DotnetApiCatalog.GenerateManagedReferenceYamlFiles("docfx.json");
             await Docfx.Docset.Build("docfx.json");
             Directory.SetCurrentDirectory(currentDirectory);
         }