# MERIDIAN
## Keepers

A keeper is a client with no body and no picture. It mines a proof-of-work chain. That chain is what makes a hole official. A vote can show the pit early. The block is the decision.

The client is [tools/archive/index.html](../tools/archive/index.html). `npm start`, then open [http://127.0.0.1:8080/tools/archive/](http://127.0.0.1:8080/tools/archive/). It announces `role: archive` on the lighthouse. A walk tab answers. Digs are still predicted locally. The archive mines a checked proposal even before the vote seals. When the block arrives, every linked client draws that tip, including one that never voted. A heavier chain replaces it. A hole you dug yourself stays on your screen until a block includes it. The walk line changes from `provisional` to `official`.

A block commits the edits since the previous tip, the chunk hash those edits produce, and a nonce. The hash of that block must have **16** leading zero bits. A heavier chain wins. Weight is `2^(bits - 8)`, so one harder block can outrank several easier ones. Ties break toward the lower block id. An empty block, a skipped seq, or a hash that does not replay is refused. The lighthouse still does not see the blocks.

## Keep

Keep is the block reward. It is not metal and not scrip. A vote, a checkpoint, and time spent linked do not mint it.

| Event | Keep |
|---|---|
| A block this key mined that is still an ancestor of the heaviest tip | 10 |

A fork that loses pays nothing. The receipt is recomputed from the tip, so an orphaned block drops off the score.

## In-game bonus

Every 30 keep, which is three blocks that are still canonical, the receipt may claim one crate: **2 metal** and **1 fiber**. The next three blocks can claim another. Keep is not spent.

The archive page records the claim. It does not add the metal to a backpack. A later acceptance pays the crate to the player key named with the receipt. Until that happens, the crate is a claim, not a balance.

## Real-world bounty

The client does not send money. It signs a receipt: the archive pubkey, the keep, the blocks, the height, and the tip it is standing on.

Suggested rate, which a treasurer may change by publishing a new one:

| | |
|---|---|
| Rate | $0.02 per keep, so $0.20 a canonical block |
| Cap | $40 per pubkey per quarter |
| Proof | The signed receipt, plus the blocks another archive or a player still holds on the heaviest chain |
| Paid to | An address the operator publishes out of band. It is not a field in the game. |

A receipt whose blocks are not on the heaviest chain is refused. One payout address per pubkey per quarter. No treasury in this repository means the receipt is the claim, not a payment.

## Between restarts

The archive keeps its own key. The same tab comes back as the same keeper, with the same keep.

It also keeps the world it has been given: official blocks, walls, and the other pieces it has seen. On the next start it puts that chain back together and, when a player links, sends it again. A hole that reached a block is still a hole after both sides restart.

A player keeps their own key in the browser. Skills, place, pack, notes, and the map picture come back with that key. The sheet is signed and handed to the archive. If the browser still has the key, the archive can hand the newer sheet back. The archive does not keep the secret. A lost key is a new person. The world they dug, once it was in a block, is still there.

The archive page shows how fast it is hashing, how long it has been up, and how many clients are linked. The walk line says how many other players and how many archives are in the simulation. `alone` means none.