diff --git a/HellionChat/Ui/StyleEngine/TypeScale.cs b/HellionChat/Ui/StyleEngine/TypeScale.cs
index fc504e6..5316b12 100644
--- a/HellionChat/Ui/StyleEngine/TypeScale.cs
+++ b/HellionChat/Ui/StyleEngine/TypeScale.cs
@@ -7,6 +7,8 @@ internal enum TypeRole
     Meta,
 }
 
+// TEST-MIRROR: Ui/TypeScaleTests.cs
+//
 // Named sizes derived from one base, so a role means the same thing wherever it
 // is drawn.
 //
diff --git a/HellionChat/Ui/StyleEngine/Widgets/ChannelHeaderDetail.cs b/HellionChat/Ui/StyleEngine/Widgets/ChannelHeaderDetail.cs
index 50b6e0a..8932830 100644
--- a/HellionChat/Ui/StyleEngine/Widgets/ChannelHeaderDetail.cs
+++ b/HellionChat/Ui/StyleEngine/Widgets/ChannelHeaderDetail.cs
@@ -2,6 +2,8 @@ using System.Globalization;
 
 namespace HellionChat.Ui.StyleEngine.Widgets;
 
+// TEST-MIRROR: Ui/ChannelHeaderDetailTests.cs
+//
 // Where you are and what time it is, as two parts rather than one string.
 //
 // They are split because they cannot share a face. The clock and a world name are
diff --git a/HellionChat/Util/LayoutFingerprint.cs b/HellionChat/Util/LayoutFingerprint.cs
index f507d07..160f22c 100644
--- a/HellionChat/Util/LayoutFingerprint.cs
+++ b/HellionChat/Util/LayoutFingerprint.cs
@@ -1,5 +1,7 @@
 namespace HellionChat.Util;
 
+// TEST-MIRROR: Util/LayoutFingerprintGateTests.cs
+//
 // Layout inputs that make a tab's cached row heights stale. Kept as a plain
 // value type so the build suite can pin the gate without an ImGui frame.
 internal readonly record struct LayoutFingerprint(