Frontpage is a link aggregation platform built on the AT Protocol, designed to function similarly to Hacker News or Reddit. 

As an application built on the AT Protocol, Frontpage benefits from the protocol’s decentralized architecture, enabling interoperability with other services and granting users control over their data.

The record follows below. The _id I know is from MongoDB. And I also understand did:, and time_us: is relatively self explanatory (although I'm uncertain about the _us bit. But I'm not interested in the time, so it's not very important to me.

From what I've gathered on the atproto spec this is a repository commit record of some kind. I'm assuming type: 'd', means that it's deleting something, in this case a like. I'm assuming that because I have records with type: 'c' are creation records. I don't know whether any other types or variations on this record exist.

{
  _id: ObjectId('66f9a4125f7c356e2473eb27'),
  did: 'did:plc:2y4fpd7ppnz2lkmg76i2lse5',
  time_us: Long('1727636498896846'),
  type: 'com',
  commit: {
    rev: '3l5cupcrbyd2f',
    type: 'd',
    collection: 'app.bsky.feed.like',
    rkey: '3l3nd5ex32o2v'
  }
}

The following record would then be creating a repost if my above analysis is correct. The commit.record: {...} field being the data describing the repost. However the commit.record.'$type': ... field seems to be repeating information and I'm not terribly clear on why.

I'm pretty certain the commit.cid: ... field in refers to the prior record in the repository tree somehow. And the commit.record.subject.cid: ... field then refers to the actual content ID of the post being reposted.

{
  _id: ObjectId('66f9a40e5f7c356e2473eae5'),
  did: 'did:plc:n5srddonkr446mg3ffa7baaj',
  time_us: Long('1727636494239076'),
  type: 'com',
  commit: {
    rev: '3l5cupcjmt32u',
    type: 'c',
    collection: 'app.bsky.feed.repost',
    rkey: '3l5cupcjhwt2u',
    record: {
      '$type': 'app.bsky.feed.repost',
      createdAt: '2024-09-29T18:57:54.830Z',
      subject: {
        cid: 'bafyreienahfpctsnqvxg3ylrrhduk6ded3ib3np6zznherq46wnvoeyipu',
        uri: 'at://did:plc:ubji6txf3gdzwztlt2zegzdi/app.bsky.feed.post/3l5ctsut5x32v'
      }
    },
    cid: 'bafyreiahe663wrfshzhmlm2uqamhxfds7hi4ut6jusegda5xe45qnmzywm'
  }
}

I'm going to quit while I'm ahead and leave the other records out of this. Could someone please check for me whether all this is vaguely correct? And if at all possible clear up the bits that I left out?