> ## Documentation Index
> Fetch the complete documentation index at: https://docs.usecarry.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# Walrus

> How Carry stores memories and receipts as real, content-addressed blobs on Walrus — and verifies them live.

[Walrus](https://www.walrus.xyz) is Carry's storage layer. Every memory and every anchored receipt is a real, content-addressed blob — not a hash placeholder — so anyone can resolve it and confirm it exists.

## How Carry talks to Walrus

Carry uses the Walrus HTTP API directly through a small client:

```ts theme={null}
// packages/carry-walrus/src/walrus-http.ts
export class WalrusHttp implements WalrusClient {
  async store(data, epochs = 5) {
    const res = await fetch(`${this.publisher}/v1/blobs?epochs=${epochs}`, {
      method: "PUT",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify(data),
    });
    const json = await res.json();
    const blobId = json.newlyCreated?.blobObject?.blobId ?? json.alreadyCertified?.blobId;
    return { blobId };
  }

  async verify(blobId) {
    const res = await fetch(`${this.aggregator}/v1/blobs/${blobId}`);
    return res.ok; // resolves on-chain? not a flag we set
  }
}
```

* **Store** — `PUT /v1/blobs?epochs=N` on the publisher returns the real blob id, which becomes the memory's `walrusRef`.
* **Verify** — `GET /v1/blobs/{id}` on the aggregator. The receipt's "verified" badge is an independent aggregator GET *anyone* can repeat.

## Public verifiability

Captured memories become **public Walrus blobs** by default — and that's deliberate. It means a receipt's "verified" badge isn't a label Carry controls; it's a check anyone can reproduce against any testnet aggregator. That public verifiability is the strongest version of the proof story.

```bash theme={null}
# resolve any Carry memory or receipt blob yourself
curl https://aggregator.walrus-testnet.walrus.space/v1/blobs/<blobId>
```

## Configuration

```bash theme={null}
WALRUS_PUBLISHER=https://publisher.walrus-testnet.walrus.space
WALRUS_AGGREGATOR=https://aggregator.walrus-testnet.walrus.space
```

<Tip>
  Set `CARRY_MODE=mock` (or omit the Walrus URLs) to use a deterministic in-memory `MockWalrus` — handy for offline development and tests.
</Tip>

## Receipts on Walrus

When an answer is anchored, the canonical receipt JSON is stored to Walrus first; its blob id and `blake2b256` digest are then recorded on-chain in the `Receipt` object. The verifier later re-fetches that blob and re-derives the digest — closing the loop between storage and proof. See [The hash chain](/onchain/hash-chain).