Aggregation Time Execution takes a lot of time

[
  {
    $match: {
      rollout_organization_domain: "swift-dev"
    }
  },
  {
    $unionWith: {
      coll: "swift-dev_extension_app_url"
    }
  },
  {
    $lookup: {
      from: "swift-dev_extension_alert",
      localField: "url",
      foreignField: "url",
      as: "alert"
    }
  },
  {
    $addFields: {
      alerts: {
        $size: "$alert"
      }
    }
  },
  {
    $unset: "alert"
  },
  {
    $lookup: {
      from: "swift-dev_extension_event_logs",
      let: {
        url: "$url"
      },
      pipeline: [
        {
          $match: {
            $expr: {
              $eq: ["$url", "$$url"]
            }
          }
        },
        {
          $group: {
            _id: "$url",
            users: {
              $addToSet: "$unmask_email"
            }
          }
        }
      ],
      as: "event_logs"
    }
  },
  {
    $addFields: {
      user_count: {
        $cond: {
          if: {
            $gt: [
              {
                $size: "$event_logs.users"
              },
              0
            ]
          },
          then: {
            $size: {
              $arrayElemAt: [
                "$event_logs.users",
                0
              ]
            }
          },
          else: 0
        }
      }
    }
  },
  {
    $project: {
      app_name: 1,
      url: 1,
      domain: 1,
      status: 1,
      category: 1,
      organization_domain: 1,
      type: 1,
      created_at: 1,
      updated_at: 1,
      alerts: 1,
      user_count: 1
    }
  }
]

Need help for optimizing the above query