diff --git a/ImperatorToCK3.UnitTests/CK3/Characters/CK3CharacterTests.cs b/ImperatorToCK3.UnitTests/CK3/Characters/CK3CharacterTests.cs
index b14ea914f..5eed9c8d7 100644
--- a/ImperatorToCK3.UnitTests/CK3/Characters/CK3CharacterTests.cs
+++ b/ImperatorToCK3.UnitTests/CK3/Characters/CK3CharacterTests.cs
@@ -114,7 +114,7 @@ public CK3CharacterBuilder WithCultureMapper(CultureMapper cultureMapper) {
 			this.cultureMapper = cultureMapper;
 			return this;
 		}
-		public CK3CharacterBuilder WithTraitMapper(TraitMapper traitMapper) {
+		internal CK3CharacterBuilder WithTraitMapper(TraitMapper traitMapper) {
 			this.traitMapper = traitMapper;
 			return this;
 		}
diff --git a/ImperatorToCK3.UnitTests/Mappers/Trait/TraitMapperTests.cs b/ImperatorToCK3.UnitTests/Mappers/Trait/TraitMapperTests.cs
index 8f536c175..e7d35b164 100644
--- a/ImperatorToCK3.UnitTests/Mappers/Trait/TraitMapperTests.cs
+++ b/ImperatorToCK3.UnitTests/Mappers/Trait/TraitMapperTests.cs
@@ -12,8 +12,8 @@ namespace ImperatorToCK3.UnitTests.Mappers.Trait;
 [Collection("Sequential")]
 [CollectionDefinition("Sequential", DisableParallelization = true)]
 public class TraitMapperTests {
-	public class TestTraitMapper : TraitMapper {
-		public TestTraitMapper(Dictionary<string, string> irToCK3TraitMap, IdObjectCollection<string, ImperatorToCK3.CK3.Characters.Trait> ck3Traits) {
+	internal class TestTraitMapper : TraitMapper {
+		internal TestTraitMapper(Dictionary<string, string> irToCK3TraitMap, IdObjectCollection<string, ImperatorToCK3.CK3.Characters.Trait> ck3Traits) {
 			ImperatorToCK3TraitMap = irToCK3TraitMap;
 			CK3Traits = ck3Traits;
 		}
diff --git a/ImperatorToCK3/CK3/Characters/Trait.cs b/ImperatorToCK3/CK3/Characters/Trait.cs
index 9ee60d178..04140b442 100644
--- a/ImperatorToCK3/CK3/Characters/Trait.cs
+++ b/ImperatorToCK3/CK3/Characters/Trait.cs
@@ -1,19 +1,18 @@
 using commonItems;
 using commonItems.Collections;
 using System.Collections.Generic;
-using System.Linq;
 
 namespace ImperatorToCK3.CK3.Characters;
-public sealed class Trait : IIdentifiable<string> {
+internal sealed class Trait : IIdentifiable<string> {
 	public string Id { get; }
-	public ISet<string> Opposites { get; private set; } = new HashSet<string>();
+	public HashSet<string> Opposites { get; private set; } = [];
 
 	public Trait(string id) {
 		Id = id;
 	}
 	public Trait(string id, BufferedReader traitReader) : this(id) {
 		var parser = new Parser();
-		parser.RegisterKeyword("opposites", reader => Opposites = reader.GetStrings().ToHashSet());
+		parser.RegisterKeyword("opposites", reader => Opposites = [.. reader.GetStrings()]);
 		parser.RegisterRegex(CommonRegexes.Catchall, ParserHelpers.IgnoreItem);
 		parser.ParseStream(traitReader);
 	}
diff --git a/ImperatorToCK3/Mappers/Trait/TraitMapper.cs b/ImperatorToCK3/Mappers/Trait/TraitMapper.cs
index e10516a36..263de70d4 100644
--- a/ImperatorToCK3/Mappers/Trait/TraitMapper.cs
+++ b/ImperatorToCK3/Mappers/Trait/TraitMapper.cs
@@ -6,7 +6,7 @@
 
 namespace ImperatorToCK3.Mappers.Trait;
 
-public class TraitMapper {
+internal class TraitMapper {
 	protected IDictionary<string, string> ImperatorToCK3TraitMap = new Dictionary<string, string>();
 	protected IdObjectCollection<string, CK3.Characters.Trait> CK3Traits = [];
 	
@@ -46,7 +46,7 @@ private void RegisterKeys(Parser parser) {
 	public string? GetCK3TraitForImperatorTrait(string impTrait) {
 		return ImperatorToCK3TraitMap.TryGetValue(impTrait, out var ck3Trait) ? ck3Trait : null;
 	}
-	public ISet<string> GetCK3TraitsForImperatorTraits(IEnumerable<string> irTraits) {
+	public HashSet<string> GetCK3TraitsForImperatorTraits(IEnumerable<string> irTraits) {
 		HashSet<string> ck3TraitsToReturn = [];
 		foreach (var irTrait in irTraits) {
 			var ck3Trait = GetCK3TraitForImperatorTrait(irTrait);