Abstract: The subject technology discloses configurations for receiving an indication of user activity from a first user with respect to a post, wherein the post includes content shared by a second user, in response to receiving the indication, an activity post providing an indication of the user activity with respect to the post is created, the activity post including the content, and a set of users that the activity post is visible to are identified, the set of users comprising one or more users selected from users associated with the first user in a social graph, the activity post is provided for display to the set of users in response to the indication.

Abstract: A system and method for per-client, per-type customizations to posts in an activity stream comprises an extraction pipeline and a rendering pipeline. The extraction pipeline can include a library of embedded code, data type taxonomy and an embed converter. The data type taxonomy is coupled to an activity source to receive activity information, and to produce a first protocol buffer. The embed converter produces a type-specific protocol buffer from the first protocol buffer and embedded code based in part upon the type of activity and the type of client. The type-specific protocol buffer is provided to the client to process activity information or present activity information. The disclosure also includes a method for processing a post in an activity stream on a per-client, per-type basis.

Abstract: The subject matter of this specification can be implemented in, among other things, a method that includes receiving a new message and providing instructions to a client device for collapsing at least one of one or more previously received messages when the number of messages reaches a number at which it is desirable to collapse the message thread. The method also includes providing instructions for appending a new message to the message thread. The method may also include instructions for providing one or more collapse or expand controls for managing message threads.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for identifying a plurality of items to be displayed to a user, each item including digital content and being associated with a respective timestamp, receiving a plurality of scores, each score being associated with an item of the plurality of items, determining a subset of items to be displayed to the user based on the plurality of scores, the subset of items including items of the plurality of items, grouping items in the subset of items based on respective timestamps to provide a plurality of item groups, for each item group, determining an order of items based on respective scores, and transmitting instructions to display items to the user based on the plurality of item groups and in the order within each item group.

Abstract: An extension system for rendering custom posts in the activity stream comprises an activity streams front end, an activity streams backend and a custom template storage. The activity streams backend is communicatively coupled to receive activity information from activity sources. Clients send custom metadata to the activity streams backend, including a key for decoding and rendering the proper templates and associated scripts on the activity streams frontend. The activity streams backend encodes this custom key and metadata as part of the activity information. The activity streams front end retrieves the encoded information and decodes the encoded information to produce data and a type. From the type, the activity streams front end accesses the custom template storage to determine the associated custom template and JavaScript. The activity streams front end cooperates with the client to use the data, custom template and JavaScript to render the activity information at the client device.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for identifying a plurality of items to be displayed to a user, each item including digital content and being associated with a respective timestamp, receiving a plurality of scores, each score being associated with an item of the plurality of items, determining a subset of items to be displayed to the user based on the plurality of scores, the subset of items including items of the plurality of items, grouping items in the subset of items based on respective timestamps to provide a plurality of item groups, for each item group, determining an order of items based on respective scores, and transmitting instructions to display items to the user based on the plurality of item groups and in the order within each item group.

Abstract: A plurality of content items for a content stream is determined by a system. The system estimates size dimensions for the content items, and determines a multidimensional layout by placing the content items into two or more adjacent containers based on the size dimensions. The system determines a difference in size between the two or more adjacent containers and adjusts an aspect of one or more of the content items to substantially equalize a size of the two or more containers.