Constant SYS_SILO_ENTER_SANDBOX 

pub const SYS_SILO_ENTER_SANDBOX: usize = 811; // 811usize

Enter sandbox mode (irreversible).

After this call, the silo cannot:

• Gain new capabilities (pledge is locked)
• Access new filesystem paths (unveil is locked)
• Execute certain privileged syscalls

This is a one-way operation : there is no way to exit sandbox mode.