To run the `simple` example with `llama.cpp` backend, use:
```bash
cargo run --example simple --features="llama.cpp-vulkan ollama" -- --llama-cpp "Who are you?"
```
To run the `simple` example with `ollama` backend, use:
```bash
cargo run --example simple --features="llama.cpp-vulkan ollama" -- --ollama "Who are you?"
```