diff --git a/.gitignore b/.gitignore
index 03f4a3c..70f8402 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 .pio
+compile_commands.json
diff --git a/src/main.cpp b/src/main.cpp
index cb61667..1d27ab7 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,3 +1,8 @@
-void setup() {}
+#include <Arduino.h>
 
-void loop() {}
+void setup() { Serial.begin(9600); }
+
+void loop() {
+  Serial.println("Hello world!");
+  delay(1000);
+}