version 1
diff --git a/gRPC.podspec b/gRPC.podspec
index f47b44f..63394db 100644
--- a/gRPC.podspec
+++ b/gRPC.podspec
@@ -391,7 +391,8 @@
                       'src/core/transport/transport_op_string.c',
                       'src/core/census/context.c',
                       'src/core/census/initialize.c',
-                      'src/core/census/record_stat.c'
+                      'src/core/census/record_stat.c',
+                      'src/core/census/tracing.c'
 
     ss.private_header_files = 'src/core/support/env.h',
                               'src/core/support/file.h',