ONNX consumes a .onnx file, which is a definition of the network and weights. GGML instead just consumes the weights, and defines the network in code.

Being bound to ONNX means moving at a slower velocity - the field moves so fast that you need complete control.

I haven't used ONNX or GGML, but presumably using GGML means you need to reimplement the network architecture?

You do! But it offers quite a fluid API making it pretty simple. You can see my attempt at a torchesque API here: https://twitter.com/fleetwood___/status/1679889450623459328