diff --git a/client/tests/fixtures/msgpack/atlas_response_ready.msgpack b/client/tests/fixtures/msgpack/atlas_response_ready.msgpack
index 39e40b709..acc81f007 100644
Binary files a/client/tests/fixtures/msgpack/atlas_response_ready.msgpack and b/client/tests/fixtures/msgpack/atlas_response_ready.msgpack differ
diff --git a/server/tests/serialization.rs b/server/tests/serialization.rs
index 62b9002b1..01f5e8902 100644
--- a/server/tests/serialization.rs
+++ b/server/tests/serialization.rs
@@ -1,5 +1,6 @@
 //! IPC serialization round-trip tests (D-030 Layer 1: fixture-based).
 
+use settled_reach_server::atlas::layer_proxy::AtlasLayerResponse;
 use settled_reach_server::bridge::types::*;
 use settled_reach_server::simulation::time::{DayPhase, TickRate};
 use std::fs;
@@ -173,6 +174,10 @@ fn all_fixtures_deserialize() {
             rmp_serde::from_slice::<ObserverSnapshot>(&bytes).unwrap_or_else(|e| {
                 panic!("deserialize boundary snapshot fixture {}: {}", name, e)
             });
+        } else if name.starts_with("atlas_response") {
+            // Atlas layer-stream responses (#969, D-225) — Ready/Pending/NotFound.
+            rmp_serde::from_slice::<AtlasLayerResponse>(&bytes)
+                .unwrap_or_else(|e| panic!("deserialize atlas_response fixture {}: {}", name, e));
         } else if name.starts_with("snapshot") {
             rmp_serde::from_slice::<ObserverSnapshot>(&bytes)
                 .unwrap_or_else(|e| panic!("deserialize snapshot fixture {}: {}", name, e));