objection.js modifyEager .as('count') doesn't seem to do anything to .count()

So I want to get the count of comments in a post rather than all the comments themselves I've got it to work with modifyEager like so but the as('count') seems to be doing nothing in this case

.eager('comments').modifyEager("comments", builder => {
    builder.count().as('count')
})

It's really tedious because commentsCount for each post has these values:

[]
[]
[]
[]
[ Post { 'count(*)': 1 } ]
[]

So I have gotten the count doing this but I'm surely doing something wrong

if(commentCount.length > 0)
    return data[0]["count(*)"]
return 0

Any ideas?

EDIT: showing the working code for reference to help people

module.exports = async (organizationId, scope) => {
    return await Post.query()
    .where("organization_id", organizationId)
    .orderBy("post_id", "desc")
    .limit(scope.limit)
    .offset(scope.offset)
    .select(
        'posts.*',
        Post.relatedQuery('comments').count().as('commentsCount')
    )
    .eager('users')
}

Couldnt test it, but the example appears at docs this way:

const posts = await Post
  .query()
  .select(
    'Post.*',
    Post.relatedQuery('comments').count().as('numberOfComments')
  );

console.log(posts[4].numberOfComments);