title: Cloud Function Affect Read/Write Quotas
body: <p>I am looking for clarification on how the actions triggered by cloud functions affect the cost of hosting an app with Firebase.</p>
  
  <p>My situation:</p>
  
  <ul>
  <li>I have a cloud function that is triggered when a post is made...that cloud function writes that post to all of the appropriate uid's on the /feed node mentioned below.</li>
  <li><p>I am using Firestore to host a feed/follow system. It is setup with each user having their own feed at the following path</p>
  
  <p><em>/feed/{uid}/posts</em></p></li>
  </ul>
  
  <p>My question is, if a user has 1,000,000 followers...does that translate to 1,000,000 writes in the eyes of Firestore?</p>
  
  <p>Does that mean that single post will cost $1.80 to distribute? Based on the cost of $0.18/100k writes.</p>
  
  <p>I am just trying to see how this will scale with thousands of users posting dozens of posts...those distribution costs seem very expensive at scale for this situation.</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>It looks like it does cost for every read/write in a cloud function base on the following video:</p>
  
  <p><a href="https://www.youtube.com/watch?time_continue=49&amp;v=6NegFl9p_sE&amp;feature=emb_logo" rel="nofollow noreferrer">https://www.youtube.com/watch?time_continue=49&amp;v=6NegFl9p_sE&amp;feature=emb_logo</a></p>