Disclosed embodiments relate to online website building using customized back-end functionality. Operations include maintaining an online database configured to store a library of website building elements for configuring a front-end of an indexable web page; transmitting instructions to a browser permitting a user to remotely access the stored library, and to permit the user to utilize a selection of the building elements for constructing the front-end of the indexable webpage; receiving specifications from user to configure a programmable event for activating user-editable code providing customized back-end functionality associated with the indexable webpage; receiving user edits to the code; storing the edited code; and in response to a trigger associated with the programmable event, executing the edited code for implementing the customized back-end functionality.