Access control system

A system comprising one or more computers and one or more storage devices on which are stored instructions that are operable, when executed by the one or more computers, to cause the one or more computers to perform operations comprising:

• detecting a person within a threshold distance of a door;
• determining that there is a threshold likelihood that the person may deliver a package;
• determining, using contextual data for the package, a delivery location for the package;
• providing first instructions that indicate the delivery location for the package;
• determining, using the contextual data for the package, a wait timer that indicates a recommended time period to wait before retrieving the package;
• generating instructions to cause presentation of a user interface that indicates the delivery location for the package;
• and
• providing, to a device and using the wait timer, the instructions to cause the device to present the user interface that indicates the delivery location for the package.

A non-transitory computer storage medium encoded with instructions that, when executed by one or more computers, cause the one or more computers to perform operations comprising:

• detecting a person within a threshold distance of a door;
• determining that there is a threshold likelihood that the person may access the door;
• providing instructions that indicate one or more criteria for access to the door;
• determining that a threshold quantity of the one or more criteria are satisfied;
• and
• in response to determining that the threshold quantity of the one or more criteria are satisfied, providing access to the door.