diff --git a/rebar.config.script b/rebar.config.script
index 99d9f90..92888e9 100644
--- a/rebar.config.script
+++ b/rebar.config.script
@@ -3,6 +3,7 @@ Project = "src/github.com/ut-proj/midiserver",
 Binary = "bin/midiserver",
 {ok, CurrentDirectory} = file:get_cwd(),
 os:putenv("PRECOMPILED_MIDISERVER", Binary),
+os:putenv("MIDI_IN", "0"),
 os:putenv("GOPATH", filename:join([CurrentDirectory, GoPrefix])),
 os:putenv("MIDISERVER", filename:join([CurrentDirectory, GoPrefix, Project, Binary])),
 os:putenv("GO111MODULE", "on"),
diff --git a/src/undermidi/go/execserver.lfe b/src/undermidi/go/execserver.lfe
index 53e998d..f933ffe 100644
--- a/src/undermidi/go/execserver.lfe
+++ b/src/undermidi/go/execserver.lfe
@@ -37,7 +37,9 @@
 (defun initial-state ()
   (let ((log-level (logjam:read-log-level "config/sys.config")))
     `#m(opts ()
-        args ("-loglevel" ,(go-log-level log-level) "-daemon" "-log-reportcaller")
+        args ("-loglevel" ,(go-log-level log-level)
+              "-daemon" "-log-reportcaller"
+              "-midi-in" ,(undermidi.go.shared:midi-in))
         binary ,(undermidi.go.shared:midiserver)
         pid undefined
         os-pid undefined)))
diff --git a/src/undermidi/go/shared.lfe b/src/undermidi/go/shared.lfe
index d3e77ba..2b7227f 100644
--- a/src/undermidi/go/shared.lfe
+++ b/src/undermidi/go/shared.lfe
@@ -8,3 +8,6 @@
   (if (use-go-src?)
     (os:getenv "MIDISERVER")
     (os:getenv "PRECOMPILED_MIDISERVER")))
+
+(defun midi-in ()
+  (os:getenv "MIDI_IN"))
\ No newline at end of file