diff --git a/desktop/flipper-server-core/src/FlipperServerImpl.tsx b/desktop/flipper-server-core/src/FlipperServerImpl.tsx
index 92865c283..f5f4d79df 100644
--- a/desktop/flipper-server-core/src/FlipperServerImpl.tsx
+++ b/desktop/flipper-server-core/src/FlipperServerImpl.tsx
@@ -275,6 +275,7 @@ export class FlipperServerImpl implements FlipperServer {
     if (!device) {
       return;
     }
+    this.devices.delete(serial);
     device.disconnect(); // we'll only destroy upon replacement
     this.emit('device-disconnected', device.info);
   }
diff --git a/desktop/flipper-server/package.json b/desktop/flipper-server/package.json
index 786a761c3..b2fbf8864 100644
--- a/desktop/flipper-server/package.json
+++ b/desktop/flipper-server/package.json
@@ -32,7 +32,7 @@
     "reset": "rimraf lib *.tsbuildinfo",
     "build": "tsc -b",
     "prepack": "yarn reset && yarn build",
-    "start": "cross-env NODE_ENV=development nodemon --watch './src/**/*.tsx' --watch '../flipper-server-core/src/**/*.tsx' --exec '../ts-node' src/index.tsx"
+    "start": "cross-env NODE_ENV=development nodemon --watch './src/**/*.tsx' --watch '../flipper-server-core/src/**/*.tsx' --exec 'yarn build && ../ts-node src/index.tsx'"
   },
   "files": [
     "lib/**/*"