diff --git a/examples/common/external_platform/BUILD.gn b/examples/common/external_platform/BUILD.gn
index 7a7fbccd5..ec4857ba8 100644
--- a/examples/common/external_platform/BUILD.gn
+++ b/examples/common/external_platform/BUILD.gn
@@ -116,6 +116,13 @@ static_library("ESP32_custom") {
     ":ESP32_custom_include",
   ]
 
+  if (chip_mdns == "platform") {
+    sources += [
+      "DnssdImpl.cpp",
+      "DnssdImpl.h",
+    ]
+  }
+
   if (chip_enable_ota_requestor) {
     sources += [
       "OTAImageProcessorImpl.cpp",