diff --git a/misc/sim/run-sim b/misc/sim/run-sim
index a2ce2b63..985fe2f3 100755
--- a/misc/sim/run-sim
+++ b/misc/sim/run-sim
@@ -1,4 +1,4 @@
 #!/bin/bash
 export GOPATH=$PWD
 go get -d yggdrasil
-go run misc/sim/treesim.go
+go run -tags debug misc/sim/treesim.go