diff --git a/builder/frameworks/arduino/arduino.py b/builder/frameworks/arduino/arduino.py
index 065e58e..75d45e4 100644
--- a/builder/frameworks/arduino/arduino.py
+++ b/builder/frameworks/arduino/arduino.py
@@ -1 +1,39 @@
-# ToDo: readout core and call correct builder script (e.g., mbed-core/arduino-core-mbed.py)
\ No newline at end of file
+# Copyright 2021-present Maximilian Gerhardt <maximilian.gerhardt@rub.de>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import sys
+from os.path import join, isfile
+
+from SCons.Script import DefaultEnvironment, SConscript
+
+env = DefaultEnvironment()
+mcu = env.BoardConfig().get("build.mcu")
+core = env.BoardConfig().get("build.core", "arduino")
+build_script = ""
+
+# select build script as either from the Earle Philhower core or
+# from the builder script contained in this platform.
+
+if core == "earlephilhower":
+    build_script = join(
+        env.PioPlatform().get_package_dir("framework-arduinopico"), "tools", "platformio-build.py")
+else:
+    build_script = join(env.PioPlatform().get_dir(), "builder", "frameworks", "arduino", "mbed-core", "arduino-core-mbed.py")
+
+if not isfile(build_script):
+    sys.stderr.write(
+        "Error: Missing PlatformIO build script %s!\n" % build_script)
+    env.Exit(1)
+
+SConscript(build_script)