CALIX is a machine intelligence controlling the systems of Secret Vault, developed by Vault-Tec. CALIX is what ZAX originally was planned to become: an advanced computer designed to be implemented in the Vaults. CALIX controls many systems of the Vault, including robots and researches. Shop-Tec, a robotic trading machine, is probably CALIX's integral part. When a conflict begins in the Secret Vault between Blake and scientists, a major explosion damages the Vault and its systems. CALIX partially malfunctions and is no longer capable of controlling the Vault's security robots. Soon chaos ensues, further aggravated by Super Mutants attacking the Vault.