diff --git a/.gitignore b/.gitignore
index 6da247f..ed909fe 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,4 @@
 /postgresql/tutorial/weather/data/
+/arduino/arduino.mk
+.dep
+*.hex
diff --git a/arduino/.env b/arduino/.env
new file mode 100644
index 0000000..7de2088
--- /dev/null
+++ b/arduino/.env
@@ -0,0 +1,2 @@
+export ARDUINODIR=~/opt/arduino-1.0.5
+export BOARD=uno
diff --git a/arduino/HelloWorld/HelloWorld.ino b/arduino/HelloWorld/HelloWorld.ino
index 2914d9b..ce2d2f6 100644
--- a/arduino/HelloWorld/HelloWorld.ino
+++ b/arduino/HelloWorld/HelloWorld.ino
@@ -1,6 +1,16 @@
 const unsigned int LED_PIN = 13;
-const unsigned int PAUSE = 500;
-const unsigned int FLASH_DURATION = 50;
+const unsigned int PAUSE = 700;
+const unsigned int FLASH_DURATION = 100;
+
+
+void flash(int n) {
+  for (int i = 0; i < n; i++) {
+    digitalWrite(LED_PIN, HIGH);
+    delay(FLASH_DURATION);
+    digitalWrite(LED_PIN, LOW);
+    delay(FLASH_DURATION);
+  }
+}
 
 
 void setup() {
@@ -15,13 +25,3 @@ void loop() {
   }
   delay(PAUSE);
 }
-
-
-void flash(int n) {
-  for (int i = 0; i < n; i++) {
-    digitalWrite(LED_PIN, HIGH);
-    delay(FLASH_DURATION);
-    digitalWrite(LED_PIN, LOW);
-    delay(FLASH_DURATION);
-  }
-}
diff --git a/arduino/HelloWorld/Makefile b/arduino/HelloWorld/Makefile
new file mode 120000
index 0000000..51c7f30
--- /dev/null
+++ b/arduino/HelloWorld/Makefile
@@ -0,0 +1 @@
+../arduino.mk
\ No newline at end of file
diff --git a/arduino/Makefile b/arduino/Makefile
new file mode 120000
index 0000000..868c6f3
--- /dev/null
+++ b/arduino/Makefile
@@ -0,0 +1 @@
+arduino.mk
\ No newline at end of file
diff --git a/arduino/setup b/arduino/setup
new file mode 100755
index 0000000..2e2c7c5
--- /dev/null
+++ b/arduino/setup
@@ -0,0 +1,5 @@
+#!/bin/bash
+set -e
+
+cd $(dirname "$BASH_SOURCE")
+curl -L -O -s http://ed.am/dev/make/arduino-mk/arduino.mk