diff --git a/examples/knx-demo/platformio-ci.ini b/examples/knx-demo/platformio-ci.ini
index a0b0a11..57c4188 100644
--- a/examples/knx-demo/platformio-ci.ini
+++ b/examples/knx-demo/platformio-ci.ini
@@ -26,7 +26,7 @@ build_flags =
 
 ;--- ESP8266 -----------------------------------------------
 [env:nodemcuv2]
-platform = espressif8266
+platform = espressif8266@2.2.3
 board = nodemcuv2
 framework = arduino
 lib_deps =
diff --git a/examples/knx-demo/platformio.ini b/examples/knx-demo/platformio.ini
index 6037a2e..6134de6 100644
--- a/examples/knx-demo/platformio.ini
+++ b/examples/knx-demo/platformio.ini
@@ -35,7 +35,7 @@ build_flags =
 
 ;--- ESP8266 -----------------------------------------------
 [env:nodemcuv2]
-platform = espressif8266
+platform = espressif8266@2.2.3
 board = nodemcuv2
 framework = arduino
 ; We consider that the this projects is opened within its project directory
@@ -43,7 +43,7 @@ framework = arduino
 lib_extra_dirs = ../../../
 
 lib_deps =
-  WifiManager
+  WifiManager@0.15.0
   knx
 
 build_flags =