diff --git a/.github/renovate.json b/.github/renovate.json
index 7d858dd..9434a6e 100644
--- a/.github/renovate.json
+++ b/.github/renovate.json
@@ -4,6 +4,17 @@
         "local>reactiveui/.github:renovate"
     ],
     "packageRules": [
+        {
+            "description": "The generator and analyzer are held at the Roslyn 4.8.0 baseline (VS 2022 17.8, .NET 8.0.1xx SDK) and must not move with the toolchain. Both ship in the version-less analyzers/dotnet/cs folder, and a compiler refuses to load a generator or analyzer built against a newer Roslyn than itself, so raising this floor silently drops every consumer on an older SDK. It is a compatibility decision, not a maintenance lag, and the only reason to change it is to raise the minimum supported SDK on purpose. Microsoft.CodeAnalysis.Analyzers is deliberately absent: it supplies analyzer-authoring rules and has no bearing on the load floor.",
+            "matchManagers": [
+                "nuget"
+            ],
+            "enabled": false,
+            "matchPackageNames": [
+                "/^Microsoft\\.CodeAnalysis\\.CSharp$/",
+                "/^Microsoft\\.CodeAnalysis\\.CSharp\\.Workspaces$/"
+            ]
+        },
         {
             "description": "Analyzer packages all gate the build through the same warnings-as-errors pass, so landing them separately just means several red CI runs in a row. Move them in one PR.",
             "matchManagers": [