Using Argon without Particle Device Cloud

Hi everyone, is it possible to code an argon to run both Wi-Fi and Ble without having to use Particle Device Cloud? Ideally i would like to connect the argon to my own web server on startup. Also programming would exclusively happen through USB

Yes, if you are willing to program the devices only by USB, you can use SYSTEM_MODE(SEMI_AUTOMATIC) to allow control over the cloud connection.

Then, from setup(), use WiFi.connect() to only connect to Wi-Fi and not to the Particle cloud. The device will breathe green instead of cyan in this mode, indiicating that you're only connected to Wi-Fi, not the Particle cloud.

You can use TCPClient (or a library that uses it) to communicate with an external service. The Argon (also P2 and Photon 2) do not natively support http or https in Device OS, though there are third-party libraries that can help.