diff --git a/doc/architecture.svg b/doc/architecture.svg
index ac7a1dc..6ceb657 100644
--- a/doc/architecture.svg
+++ b/doc/architecture.svg
@@ -24,8 +24,8 @@
   <rect class="box" x="100" y="310" width="170" height="36"/>
   <text class="label" x="185" y="333">agent.Core</text>
 
-  <rect class="box" x="340" y="310" width="130" height="36"/>
-  <text class="label" x="405" y="333">Stores</text>
+  <rect class="box" x="360" y="310" width="130" height="36"/>
+  <text class="label" x="425" y="333">Stores</text>
 
   <rect class="box" x="40" y="390" width="170" height="36"/>
   <text class="label" x="125" y="413">tools.Dispatcher</text>
@@ -41,6 +41,10 @@
   <line class="edge" x1="230" y1="346" x2="330" y2="388"/>
   <line class="edge" x1="125" y1="426" x2="125" y2="448"/>
 
+  <!-- stores wraps core primitives -->
+  <line x1="270" y1="333" x2="358" y2="333" stroke="#999" stroke-width="1.5" stroke-dasharray="4,3" marker-end="url(#arrow)"/>
+  <text class="elabel" x="314" y="326">wrapped by</text>
+
   <!-- ===== 9P region ===== -->
   <rect class="region region-9p" x="110" y="145" width="220" height="75"/>
   <text class="rlabel" x="130" y="162">olliesrv (9P server)</text>
@@ -53,7 +57,7 @@
   <text class="elabel" x="185" y="260">imports</text>
 
   <!-- 9P consumes stores -->
-  <line class="edge" x1="300" y1="200" x2="405" y2="308"/>
+  <line class="edge" x1="300" y1="200" x2="425" y2="308"/>
   <text class="elabel" x="375" y="245">consumes</text>
 
   <!-- ===== External consumers ===== -->