diff --git a/src/config/device.rs b/src/config/device.rs
index 4ed4c3a..b9ee9e0 100644
--- a/src/config/device.rs
+++ b/src/config/device.rs
@@ -33,7 +33,9 @@ impl DeviceConfig {
         let mut r = Vec::new();
         if let Some(ev) = v {
             for e in ev {
-                r.push( e.run(Event::new().make_env(None, false)?.to_map(e.envconf.as_ref()))? ) ;
+                if let Some(v) = e.run(Event::new().make_env(None, false)?.to_map(e.envconf.as_ref()))? {
+                    r.push(v);
+                }
             }
         }
         Ok(r)
diff --git a/src/config/run.rs b/src/config/run.rs
index b499a00..104fdd6 100644
--- a/src/config/run.rs
+++ b/src/config/run.rs
@@ -1,5 +1,5 @@
 use std::collections::HashMap;
-use std::process::Command;
+use std::process::{Command, ExitStatus};
 
 use super::serializer::RunConfigSerializer;
 use super::EventEnvMap;
@@ -8,15 +8,24 @@ use super::EventEnvMap;
 pub struct RunConfig {
     pub args: Vec<String>,
     pub envconf: Option<EventEnvMap>,
+    pub detach: bool,
 }
 
 impl RunConfig {
-    pub fn run(&self, env: HashMap<&str, String>) -> Result<std::process::ExitStatus, std::io::Error> {
+    pub fn run(&self, env: HashMap<&str, String>) -> Result<Option<ExitStatus>, std::io::Error> {
         let mut c = Command::new(&self.args[0]);
         if self.args.len() > 1 {
             c.args(&self.args[1..]);
         }
-        c.envs(env).status()
+        c.envs(env);
+        if self.detach {
+            std::thread::spawn(move || {
+                c.status()
+            });
+            Ok(None)
+        } else {
+            c.status().map(|v| Some(v))
+        }
     }
 }
 
@@ -36,6 +45,7 @@ impl TryFrom<RunConfigSerializer> for RunConfig {
             RunConfig {
                 args,
                 envconf: v.envconf,
+                detach: v.detach.unwrap_or(false),
             }
         )
     }
diff --git a/src/config/serializer/run.rs b/src/config/serializer/run.rs
index c06ff84..87556e0 100644
--- a/src/config/serializer/run.rs
+++ b/src/config/serializer/run.rs
@@ -8,4 +8,5 @@ pub struct RunConfigSerializer {
     pub args: Option<Vec<String>>,
     pub cmd:  Option<String>,
     pub envconf: Option<EventEnvSerializer>,
+    pub detach: Option<bool>,
 }
diff --git a/test/vmpk.yml b/test/vmpk.yml
index d5057d1..a9546b0 100644
--- a/test/vmpk.yml
+++ b/test/vmpk.yml
@@ -23,6 +23,12 @@ devices:
         channel: 0
         run:
           - cmd: "echo [$channel] NoteOn $id $value $raw"
+      - type: NoteOff
+        id: 30-127
+        channel: 0
+        run:
+          - cmd: "for I in $(seq 1 3) ; do echo wait $I ; sleep 1; done"
+            detach: true
       - type: PitchBend
         remap: 0-100
         float: true