Keybase allows you (nay, encourages you) to set up a "paper key", which is a private key that you store offline (e.g. print it out and stick it in a safe). You

Keybase allows you (nay, encourages you) to set up a "paper key", which is a private key that you store offline (e.g. print it out and stick it in a safe). You can then use this paper key to provision new devices. This way if you lose all of your devices simultaneously (or just have one device to begin with) you don't need to go through an account reset to add a new device. Note that even with this, any new device added using the paper key still generates its own independent private key. Having per-device private keys is important to be able to revoke devices, and to be able to track which devices were responsible for any given action.