diff --git a/lignumis/scripts/to-nauvis.lua b/lignumis/scripts/to-nauvis.lua
index 8e8d634..cb54aa0 100644
--- a/lignumis/scripts/to-nauvis.lua
+++ b/lignumis/scripts/to-nauvis.lua
@@ -101,6 +101,7 @@ end
 
 
 local function explode_silo(silo)
+    if not silo.valid then return end
     silo.die()
 end