diff --git a/.changes/fix-before-dev-command-kill.md b/.changes/fix-before-dev-command-kill.md
new file mode 100644
index 000000000..bd1b8ce4f
--- /dev/null
+++ b/.changes/fix-before-dev-command-kill.md
@@ -0,0 +1,5 @@
+---
+"cli.rs": patch
+---
+
+Properly kill `beforeDevCommand` process.
diff --git a/tooling/cli.rs/src/dev.rs b/tooling/cli.rs/src/dev.rs
index d547e3b6a..5864f2b5d 100644
--- a/tooling/cli.rs/src/dev.rs
+++ b/tooling/cli.rs/src/dev.rs
@@ -29,7 +29,18 @@ static BEFORE_DEV: OnceCell<Mutex<Child>> = OnceCell::new();
 
 fn kill_before_dev_process() {
   if let Some(child) = BEFORE_DEV.get() {
-    let _ = child.lock().unwrap().kill();
+    let mut child = child.lock().unwrap();
+    #[cfg(windows)]
+    let _ = Command::new("powershell")
+      .arg("-Command")
+      .arg(format!("function Kill-Tree {{ Param([int]$ppid); Get-CimInstance Win32_Process | Where-Object {{ $_.ParentProcessId -eq $ppid }} | ForEach-Object {{ Kill-Tree $_.ProcessId }}; Stop-Process -Id $ppid }}; Kill-Tree {}", child.id()))
+      .status();
+    #[cfg(not(windows))]
+    let _ = Command::new("pkill")
+      .args(&["-TERM", "-P"])
+      .arg(child.id().to_string())
+      .status();
+    let _ = child.kill();
   }
 }