Activity feed

Every entry in an activity feed is one sentence with three slots: someone did something to something. “Rosa opened Rebuild the west quay.” “Ivo pushed two commits to main.” The grammar is what makes a feed of mixed event types readable as one list, and it is also what makes a feed easy to get wrong, because an entry missing its object (“Rosa made a change”) is a notification that has forgotten to say what happened. Write the sentence first and lay the row out around it, rather than designing a row and hoping the words fit.

Activity feed, news feed, timeline, and audit log are not the same thing. An activity feed is chronological: it is a record, and its order is time. A news feed is ranked, which means an algorithm decides what you see and time is only one signal, and calling a ranked surface a timeline is where a lot of user confusion about missing posts comes from. An audit log is chronological too, but it is exhaustive, immutable, and built to be searched and exported, because someone will eventually have to answer a question about a specific hour six months ago. A feed designed for glancing and a log designed for evidence want opposite things from filtering, retention, and detail.

Volume is the design problem. A busy object generates dozens of near-identical events, so feeds group: forty stars become “Jo and 39 others starred harbour-kit”, and eight commits in a minute become one push. Grouping is by actor, by verb, by object, or by time window, and the choice changes what the feed is for. Relative times (“4m”, “2h”) are right for the recent end where “how long ago” is the question, and wrong for the old end where “which day” is; most feeds switch to a date once past yesterday and keep the exact timestamp in a title attribute for anyone who needs it.

New entries arrive at the top, which is the one place they can arrive without pushing the row the reader is currently reading. Even so, an insert that happens while someone is halfway down the list should not move their scroll position, and a feed that inserts continuously is usually better off holding new items behind a “3 new updates” button so arrival is the reader’s decision. If arrivals are announced, a live region set to polite is enough; a feed that interrupts on every event is a feed nobody keeps open. And the empty state matters more here than in most lists, because a new account’s feed is empty by definition and “Nothing here” tells them nothing about what would ever put something there.