diff --git a/nodes/CMakeLists.txt b/nodes/CMakeLists.txt
index 4de34fb..3c3210e 100644
--- a/nodes/CMakeLists.txt
+++ b/nodes/CMakeLists.txt
@@ -2,6 +2,6 @@
 
 cmake_minimum_required(VERSION 3.20.0)
 find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
-project(blinky)
+project(plein_de_eeeeeeeeeeee)
 
-target_sources(app PRIVATE src/main.c)
+target_sources(app PRIVATE src/main.c src/window_status.c src/window_status.h src/thermometer.c src/thermometer.h src/hygrometer.c src/hygrometer.h src/co2_level.c src/co2_level.h src/supervisor.c src/supervisor.h src/ble_advertiser.c src/ble_advertiser.h)
diff --git a/nodes/src/ble_advertiser.c b/nodes/src/ble_advertiser.c
new file mode 100644
index 0000000..e69de29
diff --git a/nodes/src/ble_advertiser.h b/nodes/src/ble_advertiser.h
new file mode 100644
index 0000000..020a938
--- /dev/null
+++ b/nodes/src/ble_advertiser.h
@@ -0,0 +1,4 @@
+#ifndef BLE_ADVERTISER_H
+#define BLE_ADVERTISER_H
+
+#endif //BLE_ADVERTISER_H
diff --git a/nodes/src/co2_level.c b/nodes/src/co2_level.c
new file mode 100644
index 0000000..56bc09a
--- /dev/null
+++ b/nodes/src/co2_level.c
@@ -0,0 +1,9 @@
+#include "co2_level.h"
+
+enum error_code co2_lvl_init(){
+    return success;
+}
+
+int co2_lvl_get_value(){
+    return 0;
+}
diff --git a/nodes/src/co2_level.h b/nodes/src/co2_level.h
new file mode 100644
index 0000000..775650f
--- /dev/null
+++ b/nodes/src/co2_level.h
@@ -0,0 +1,9 @@
+#ifndef CO2_LEVEL_H
+#define CO2_LEVEL_H
+
+#include "error_code.h"
+
+enum error_code co2_lvl_init();
+int co2_lvl_get_value();
+
+#endif //CO2_LEVEL_H
diff --git a/nodes/src/error_code.h b/nodes/src/error_code.h
new file mode 100644
index 0000000..6b382d7
--- /dev/null
+++ b/nodes/src/error_code.h
@@ -0,0 +1,9 @@
+#ifndef ERROR_CODE_H
+#define ERROR_CODE_H
+
+enum error_code{
+    success = 0,
+    error_code_last,    // iteration purpose
+};
+
+#endif //ERROR_CODE_H
diff --git a/nodes/src/hygrometer.c b/nodes/src/hygrometer.c
new file mode 100644
index 0000000..eaef5f3
--- /dev/null
+++ b/nodes/src/hygrometer.c
@@ -0,0 +1,9 @@
+#include "hygrometer.h"
+
+enum error_code hygro_init(){
+    return success;
+}
+
+int hygro_get_value(){
+    return 0;
+}
diff --git a/nodes/src/hygrometer.h b/nodes/src/hygrometer.h
new file mode 100644
index 0000000..433411c
--- /dev/null
+++ b/nodes/src/hygrometer.h
@@ -0,0 +1,9 @@
+#ifndef HYGROMETER_H
+#define HYGROMETER_H
+
+#include "error_code.h"
+
+enum error_code hygro_init();
+int hygro_get_value();
+
+#endif //HYGROMETER_H
diff --git a/nodes/src/main.c b/nodes/src/main.c
index 0cf26c9..aca0509 100644
--- a/nodes/src/main.c
+++ b/nodes/src/main.c
@@ -8,41 +8,9 @@
 #include <zephyr/kernel.h>
 #include <zephyr/drivers/gpio.h>
 
-/* 1000 msec = 1 sec */
-#define SLEEP_TIME_MS   10000
-
-/* The devicetree node identifier for the "led0" alias. */
-#define LED0_NODE DT_ALIAS(led0)
-
-/*
- * A build error on this line means your board is unsupported.
- * See the sample documentation for information on how to fix this.
- */
-static const struct gpio_dt_spec led = GPIO_DT_SPEC_GET(LED0_NODE, gpios);
-
-int main(void)
-{
-	int ret;
-	bool led_state = true;
-
-	if (!gpio_is_ready_dt(&led)) {
-		return 0;
-	}
-
-	ret = gpio_pin_configure_dt(&led, GPIO_OUTPUT_ACTIVE);
-	if (ret < 0) {
-		return 0;
-	}
-
-	while (1) {
-		ret = gpio_pin_toggle_dt(&led);
-		if (ret < 0) {
-			return 0;
-		}
-
-		led_state = !led_state;
-		printf("LED state: %s\n", led_state ? "ON" : "OFF");
-		k_msleep(SLEEP_TIME_MS);
-	}
+int main(void){
+    supervisor_init();
+    supervisor_run();
+    // should never come here
 	return 0;
 }
diff --git a/nodes/src/supervisor.c b/nodes/src/supervisor.c
new file mode 100644
index 0000000..717c272
--- /dev/null
+++ b/nodes/src/supervisor.c
@@ -0,0 +1,10 @@
+#include "supervisor.h"
+
+enum error_code supervisor_init(){
+    return success;
+}
+
+enum error_code supervisor_run(){
+    while(1);
+    return success;
+}
diff --git a/nodes/src/supervisor.h b/nodes/src/supervisor.h
new file mode 100644
index 0000000..d946ae9
--- /dev/null
+++ b/nodes/src/supervisor.h
@@ -0,0 +1,14 @@
+#ifndef SUPERVISOR_H
+#define SUPERVISOR_H
+
+#include "error_code.h"
+
+#include "window_status.h"
+#include "thermometer.h"
+#include "hygrometer.h"
+#include "co2_level.h"
+
+enum error_code supervisor_init();
+enum error_code supervisor_run();
+
+#endif //SUPERVISOR_H
diff --git a/nodes/src/thermometer.c b/nodes/src/thermometer.c
new file mode 100644
index 0000000..cb8e4de
--- /dev/null
+++ b/nodes/src/thermometer.c
@@ -0,0 +1,9 @@
+#include "thermometer.h"
+
+enum error_code thermo_init(){
+    return success;
+}
+
+int thermo_get_value(){
+    return 0;
+}
diff --git a/nodes/src/thermometer.h b/nodes/src/thermometer.h
new file mode 100644
index 0000000..d0cb5f0
--- /dev/null
+++ b/nodes/src/thermometer.h
@@ -0,0 +1,9 @@
+#ifndef THERMOMETER_H
+#define THERMOMETER_H
+
+#include "error_code.h"
+
+enum error_code thermo_init();
+int thermo_get_value();
+
+#endif //THERMOMETER_H
diff --git a/nodes/src/window_status.c b/nodes/src/window_status.c
new file mode 100644
index 0000000..5f5d3ef
--- /dev/null
+++ b/nodes/src/window_status.c
@@ -0,0 +1,9 @@
+#include "window_status.h"
+
+enum error_code window_init(){
+    return success;
+}
+
+int window_get_value(){
+    return 0;
+}
diff --git a/nodes/src/window_status.h b/nodes/src/window_status.h
new file mode 100644
index 0000000..3f5ac83
--- /dev/null
+++ b/nodes/src/window_status.h
@@ -0,0 +1,9 @@
+#ifndef WINDOW_STATUS_H
+#define WINDOW_STATUS_H
+
+#include "error_code.h"
+
+enum error_code window_init();
+int window_get_value();
+
+#endif //WINDOW_STATUS_