diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index a8b65e450..0dafd02d7 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -12,7 +12,7 @@ updates:
     directory: "/ImperatorToCK3.UnitTests/"
     # Check the nuget registry for updates every day (weekdays) schedule:
     schedule:
-      interval: "daily"
+      interval: "weekly"
 
   - package-ecosystem: "github-actions"
     # Workflow files stored in the
diff --git a/ImperatorToCK3/CK3/Dynasties/HouseCollection.cs b/ImperatorToCK3/CK3/Dynasties/HouseCollection.cs
index c59d6defc..61acd1a7b 100644
--- a/ImperatorToCK3/CK3/Dynasties/HouseCollection.cs
+++ b/ImperatorToCK3/CK3/Dynasties/HouseCollection.cs
@@ -2,6 +2,7 @@
 using commonItems.Collections;
 using commonItems.Mods;
 using ImperatorToCK3.CK3.Characters;
+using System.Collections.Generic;
 using System.Linq;
 
 namespace ImperatorToCK3.CK3.Dynasties;
@@ -22,7 +23,7 @@ public void LoadCK3Houses(ModFilesystem ck3ModFS) {
 	public void PurgeUnneededHouses(CharacterCollection ck3Characters, Date date) {
 		Logger.Info("Purging unneeded dynasty houses...");
 
-		var houseIdsToKeep = ck3Characters
+		HashSet<string> houseIdsToKeep = ck3Characters
 			.Select(c => c.GetDynastyHouseId(date))
 			.Where(id => id is not null)
 			.Distinct()