Cutoff Date

Some activity selectors have no cutoff by default and scan your feed's entire history on every read. That's fine in development, but with a filter on a large production dataset it becomes a performance risk.

Without a filter, the newest activities are usually enough and the read is fast. Add a filter with no cutoff and the search has no time bound: a selective filter (few or no recent matches) can scan huge amounts of history and time out with a 500, often only after launch once data has grown. A cutoff_window bounds the scan, so a selective filter returns "nothing in the window" quickly.

Rule of thumb: if a selector uses a filter that runs at read time, set a cutoff_window.

Which selectors need this

current_feed supports richer filters (search_data, text, near) that force read-time computation: the path a cutoff protects.

How to set a cutoff

Set cutoff_window on the selector: a relative duration ("the last N ..."). Units: s, m, h, d, w, y (for example "12h", "7d", "2w"); minimum 1 hour.

// Bound a filtered current_feed scan to the last 14 days.
await client.feeds.createFeedGroup({
  id: "team_updates",
  activity_selectors: [
    {
      type: "current_feed",
      filter: {
        search_data: { $contains: { category: "announcement" } },
      },
      cutoff_window: "14d",
    },
  ],
});

# Bound a filtered current_feed scan to the last 14 days.
response = client.feeds.create_feed_group(
    id="team_updates",
    activity_selectors=[
        {
            "type": "current_feed",
            "filter": {
                "search_data": {"$contains": {"category": "announcement"}},
            },
            "cutoff_window": "14d",
        }
    ],
)

# Bound a filtered current_feed scan to the last 14 days.
create_request = GetStream::Generated::Models::CreateFeedGroupRequest.new(
  id: 'team_updates',
  activity_selectors: [
    GetStream::Generated::Models::ActivitySelectorConfig.new(
      type: 'current_feed',
      filter: {
        search_data: { '$contains' => { category: 'announcement' } }
      },
      cutoff_window: '14d'
    )
  ]
)

response = client.feeds.create_feed_group(create_request)

use GetStream\GeneratedModels\CreateFeedGroupRequest;
use GetStream\GeneratedModels\ActivitySelectorConfig;

// Bound a filtered current_feed scan to the last 14 days.
$response = $feedsClient->createFeedGroup(
    new CreateFeedGroupRequest(
        id: "team_updates",
        activitySelectors: [
            new ActivitySelectorConfig(
                type: "current_feed",
                filter: (object)[
                    'search_data' => (object)[
                        '$contains' => (object)[
                            'category' => 'announcement',
                        ],
                    ],
                ],
                cutoffWindow: "14d"
            )
        ]
    )
);

// Bound a filtered current_feed scan to the last 14 days.
response, err := client.Feeds().CreateFeedGroup(context.Background(), &getstream.CreateFeedGroupRequest{
  ID: "team_updates",
  ActivitySelectors: []getstream.ActivitySelectorConfig{
    {
      Type: getstream.PtrTo("current_feed"),
      Filter: map[string]any{
        "search_data": map[string]any{
          "$contains": map[string]any{
            "category": "announcement",
          },
        },
      },
      CutoffWindow: getstream.PtrTo("14d"),
    },
  },
})
if err != nil {
  log.Fatal("Error creating feed group:", err)
}

// Bound a filtered current_feed scan to the last 14 days.
var response = await _feedsV3Client.CreateFeedGroupAsync(new CreateFeedGroupRequest
{
    ID = "team_updates",
    ActivitySelectors = new List<ActivitySelectorConfig>
    {
        new()
        {
            Type = "current_feed",
            Filter = new Dictionary<string, object>
            {
                ["search_data"] = new Dictionary<string, object>
                {
                    ["$contains"] = new Dictionary<string, object>
                    {
                        ["category"] = "announcement"
                    }
                }
            },
            CutoffWindow = "14d"
        }
    }
});

// Bound a filtered current_feed scan to the last 14 days.
Map<String, Object> filter = Map.of(
    "search_data", Map.of(
        "$contains", Map.of("category", "announcement")
    )
);

CreateFeedGroupRequest request = CreateFeedGroupRequest.builder()
    .id("team_updates")
    .activitySelectors(List.of(
        ActivitySelectorConfig.builder()
            .type("current_feed")
            .filter(filter)
            .cutoffWindow("14d")
            .build()
    ))
    .build();

CreateFeedGroupResponse response = feedsClient.createFeedGroup(request).execute().getData();

Choosing a window

• Match scroll depth: 7d to 14d suits most hot feeds; keep older content in search or an archive.
• Narrower filters need shorter windows.
• Start conservative, widen later if needed.