Email system dynamic extension creation via programmatic interfaces

A method comprising:

• receiving, via a programmatic interface associated with an email server, one or more commands of an extension that are entered by an administrator associated with an email application and configured to execute a function added to the email application, the email server hosting the email application, and the function being configured to be executed based on one or more triggering criteria;
• pushing the function to the email application via the extension by caching the one or more commands in settings of an email mailbox of a user at a client device and at the email server;
• and
• in response to detecting occurrence of at least one of the triggering criteria and that the client device has no connectivity to the email server, executing the function based on the one or more commands cached in the settings of the email mailbox at the client device.

A non-transitory computer readable medium on which are stored instructions that, when executed, cause a programmable device to perform functions of:

• receiving, via a programmatic interface on a client device, one or more commands of an extension that are entered by a user of an email application and configured to execute a function added to the email application, the function being configured to be executed based on one or more triggering criteria;
• adding the function to the email application by caching the one or more commands in settings of an email mailbox of the user at the client device and at an email server, wherein the email server hosts the email application;
• and
• in response to detecting occurrence of at least one of the triggering criteria, executing the function based on the one or more commands cached in the settings of the email mailbox at the client device.