diff --git a/iris/android-app/src/devlog.rs b/iris/android-app/src/devlog.rs
index 6d6a608..7e9c022 100644
--- a/iris/android-app/src/devlog.rs
+++ b/iris/android-app/src/devlog.rs
@@ -30,6 +30,11 @@ use std::sync::OnceLock;
 /// `seq`, `t_ms`, `level`, `target`, `message`, in that order. The Java
 /// side has the same constant, and the two are the one place the shape is
 /// written down on each side.
+///
+/// Gated with its one reader: the tabs demo links no `client-core` and so
+/// has no ring to lay out, and an ungated constant is a warning in that
+/// build (`iris-android-app` without `transcript-screen`).
+#[cfg(feature = "transcript-screen")]
 const FIELDS_PER_LINE: usize = 5;
 
 /// The authority the provider registered itself under, once it has been