Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the issue has not already been raised

Issue

Upgrading to v9 and the following snippet gives a type error:

  const matchCondition: QueryFilter<Job> = {};

  if (isComplete) {
    matchCondition.completedAt = { $exists: true };
  } else {
    matchCondition.completedAt = { $exists: false };
  }

  const jobs = await JobModel.aggregate<Job>([
    { $match: matchCondition },
  ]);

The matchCondition here has to be a QueryFilter<any> type for this code to build, but I would like to be able to use my Job type here like I could in v8.