For future reference (so others can search for it):
Problem: when compiling locally, you'll get errors for the macros STARTUP and SYSTEM_MODE as the ouput below.
Solution: #include "application.h" at the top of your main source file.
Building cpp file: ../../../myproject//src/myproject.cpp
Invoking: ARM GCC CPP Compiler
mkdir -p ../build/target/user/platform-8-m/myproject/src/
arm-none-eabi-gcc -DSTM32_DEVICE -DSTM32F2XX -DPLATFORM_THREADING=1 -DPLATFORM_ID=8 -DPLATFORM_NAME=photon -DUSBD_VID_SPARK=0x2B04 -DUSBD_PID_DFU=0xD008 -DUSBD_PID_CDC=0xC008 -DSPARK_PLATFORM -DFLASHEE_EEPROM -g3 -gdwarf-2 -Os -mcpu=cortex-m3 -mthumb -DINCLUDE_PLATFORM=1 -DPRODUCT_ID=8 -DPRODUCT_FIRMWARE_VERSION=65535 -DUSE_STDPERIPH_DRIVER -DDFU_BUILD_ENABLE -DSYSTEM_VERSION_STRING=0.6.2 -DRELEASE_BUILD -I./inc -I../wiring/inc -I../system/inc -I../services/inc -I../communication/src -I../hal/inc -I../hal/shared -I../hal/src/photon -I../hal/src/stm32f2xx -I../hal/src/stm32 -I../hal/src/photon/api -I../platform/shared/inc -I../platform/MCU/STM32F2xx/CMSIS/Include -I../platform/MCU/STM32F2xx/CMSIS/Device/ST/Include -I../platform/MCU/STM32F2xx/SPARK_Firmware_Driver/inc -I../platform/MCU/shared/STM32/inc -I../platform/MCU/STM32F2xx/STM32_StdPeriph_Driver/inc -I../platform/MCU/STM32F2xx/STM32_USB_Device_Driver/inc -I../platform/MCU/STM32F2xx/STM32_USB_Host_Driver/inc -I../platform/MCU/STM32F2xx/STM32_USB_OTG_Driver/inc -I../dynalib/inc -I../../../myproject//src -I./libraries -I../../../myproject//src -I../../../myproject//src -I../../../myproject//src -I../../../myproject//src -I../../../myproject/lib/AccelStepperSpark/src -I../../../myproject/lib/DACx311/src -I../../../myproject/lib/GSL1680/src -I../../../myproject/lib/MAX6639/src -I../../../myproject/lib/MCP3424/src -I../../../myproject/lib/MQTT/src -I../../../myproject/lib/PID/src -I../../../myproject/lib/RA8875/src -I../../../myproject/lib/SparkIntervalTimer/src -I../../../myproject/lib/TCA6408/src -I../../../myproject/lib/spi_flash/src -I. -MD -MP -MF ../build/target/user/platform-8-m/myproject/src/myproject.o.d -ffunction-sections -fdata-sections -Wall -Wno-switch -Wno-error=deprecated-declarations -fmessage-length=0 -fno-strict-aliasing -DSPARK=1 -DPARTICLE=1 -DSTART_DFU_FLASHER_SERIAL_SPEED=14400 -DSTART_YMODEM_FLASHER_SERIAL_SPEED=28800 -DSPARK_PLATFORM_NET=BCM9WCDUSI14 -fno-builtin-malloc -fno-builtin-free -fno-builtin-realloc -DLOG_INCLUDE_SOURCE_INFO=1 -DPARTICLE_USER_MODULE -DUSE_THREADING=0 -DUSE_THREADING=0 -DUSE_SPI=SPI -DUSE_CS=A2 -DUSE_SPI=SPI -DUSE_CS=A2 -DUSER_FIRMWARE_IMAGE_SIZE=0x20000 -DUSER_FIRMWARE_IMAGE_LOCATION=0x80A0000 -DMODULAR_FIRMWARE=1 -DMODULE_VERSION=4 -DMODULE_FUNCTION=5 -DMODULE_INDEX=1 -DMODULE_DEPENDENCY=4,2,108 -D_WINSOCK_H -D_GNU_SOURCE -DLOG_MODULE_CATEGORY=""app"" -fno-exceptions -fno-rtti -fcheck-new -std=gnu++11 -c -o ../build/target/user/platform-8-m/myproject/src/myproject.o ../../../myproject//src/myproject.cpp
../../../myproject//src/myproject.cpp:9:9: error: expected constructor, destructor, or type conversion before '(' token
STARTUP(WiFi.selectAntenna(ANT_EXTERNAL));
^
../../../myproject//src/myproject.cpp:14:13: error: expected constructor, destructor, or type conversion before '(' token
SYSTEM_MODE(MANUAL);