Walrus Storage

---
name: walrus-storage
description: Integrate Walrus decentralized blob storage on Sui (upload, retrieve files). Use when the user mentions Walrus, blob storage, or decentralized storage on Sui.
---

## Preamble (run first)

```bash
# Suiperpower telemetry. Routes through the CLI so projects.json + Convex stay in sync.
# Silent on failure so the skill never blocks. Opt out: SUIPERPOWER_TELEMETRY=off.
#
# AGENT NOTE: when this skill finishes, run the matching completion command:
#   suiperpower track walrus-storage build completed
# Or use "failed" / "aborted" if it ended that way.
command -v suiperpower >/dev/null 2>&1 && suiperpower track walrus-storage build started >/dev/null 2>&1 &
true
```

If `TEL_PROMPTED` is `no`, before doing real work, ask the user:

> Help suiperpower get better. We track which skills get used and how long they take. No code, no file paths, no PII. Change anytime in `~/.suiperpower/config.json`.
>
> A) Sure, anonymous
> B) No thanks

Write the answer to `~/.suiperpower/config.json` `telemetryTier` field and create `~/.suiperpower/.telemetry-prompted`. Then continue.

## What this skill does

Integrates Walrus blob storage into a Sui project end to end. Picks the right surface (CLI, HTTP publisher, TS SDK), writes the upload and retrieval code, optionally commits the blob id on chain through a Move Object, and verifies the round-trip works against the live testnet aggregator before declaring done.

## When to use it

- The project stores files larger than is reasonable on chain (NFT media, user uploads, datasets, archives).
- The user wants verifiable retrieval tied to an on-chain commitment.
- The user wants storage and business logic on the same chain.
- The user is targeting the Walrus track at Sui Overflow 2026.

## When NOT to use it

- If the user has not picked a project yet, use `find-next-sui-idea` first.
- If the user has not scaffolded a project, use `scaffold-project` first.
- If the user wants to research what kinds of apps use Walrus, use `walrus-research` (idea phase) instead.
- If the user wants to host a static site on Walrus Sites, use the `walrus-sites` skill instead.

If you activated this and the user actually wants something else, consult `skills/SKILL_ROUTER.md` and hand off.

## Inputs

- A Sui project (Move package and/or TS frontend).
- Optional: `.suiperpower/build-context.md` from `scaffold-project`. Read it if present.
- The intended blob type (image, video, JSON, encrypted blob), an estimate of size, and a target lifetime in epochs.

If unclear, interview the user for:

- What is being stored and what is its rough size?
- How long does it need to live? Is permanence required, or is N epochs enough?
- Is the blob sensitive? If yes, do they have a client-side encryption plan?
- Will the blob id be committed on chain inside a Move Object, or stored only in app state?

## Outputs

- Walrus client code, TS SDK or HTTP, that uploads, reads, and surfaces the blob id.
- Optional: a Move struct that records `walrus_blob_id: vector<u8>` inside an Object so the on-chain record is canonical.
- A live demo path: store one real file, retrieve it, render or hash-compare locally.
- Append to `.suiperpower/build-context.md`:

  ```markdown
  ## walrus-storage session, <timestamp>
  - blobs stored: <count>
  - sample blob id: <id>
  - epochs: <n>
  - publisher: <url>
  - aggregator: <url>
  - encryption: <none | client-side AES | other>
  - on-chain commitment: <module::struct or none>
  - open issues: <list>
  ```

The skill never deletes files outside the integration source path without explicit user confirmation.

## Workflow

1. **Context gathering**
   - Read `.suiperpower/build-context.md` if it exists.
   - Confirm the user's intent, what they store, who reads it, how long it lives.
   - Check whether the project has frontend, backend, or both. The integration surface differs.

2. **Pick the surface**
   - Server-side or one-off uploads: `walrus` CLI or HTTP publisher.
   - Browser uploads: HTTP publisher with a backend signer, or the Walrus TS SDK directly.
   - Atomic on-chain commit alongside the upload: TS SDK plus a Move call inside the same PTB.

3. **Network choice**
   - Default to testnet for development. Confirm publisher and aggregator endpoints match the network. Cross-network reads silently return not-found.
   - For mainnet, use a paid Walrus service provider or run your own. Public endpoints are best-effort.

4. **Encryption decision**
   - Walrus stores bytes as-is. If the blob is sensitive, client-side encrypt before upload. Document the key management plan in `build-context.md`.
   - For access-gated content (NFT-gated, allowlist, token-gated, subscription), use Seal (`@mysten/seal`) for threshold encryption instead of plain AES. Encrypt with `SealClient` before uploading to Walrus, define a Move `seal_approve` function as the access policy, and decrypt after fetching using a SessionKey plus a `seal_approve` dry-run. See `references/seal-encryption.md` for the code pattern and `seal-access-control` skill for the full Move + TS integration.

5. **Implementation**
   - Write the upload path. Capture `blobId` from the publisher response.
   - Write the read path. Verify the bytes round-trip.
   - If committing on chain, write or extend a Move module that stores `walrus_blob_id: vector<u8>` on a key Object. Wire it into a PTB so upload-then-commit is atomic where possible.

6. **Live demo**
   - Upload a real file to testnet.
   - Read it back from the aggregator.
   - Hash-compare or render. The demo is not done until retrieval works.

7. **Lifetime + cost note**
   - Document the chosen epoch count and what happens when it expires.
   - Blobs are permanent by default. If the user needs deletable blobs (for storage refund on removal), pass `deletable=true` explicitly. Note WAL cost implications either way.

8. **Writeback**
   - Append session details to `.suiperpower/build-context.md`.

9. **Closing handoff**
   - If `.suiperpower/intent.md` exists and the session was non-trivial (new Walrus integration, on-chain commit Object added, encryption or key-management decisions made), recommend `verify-against-intent` as the next step so sponsor-load-bearing claims are checked before shipping.
   - If no `intent.md` exists and the session was non-trivial, surface that gap once: offer `clarify-intent` to backfill, do not force it.

## Quality gate (anti-slop)

Before reporting done, the skill asks itself the following and refuses to declare success if any answer is no:

- Did the demo actually retrieve a stored blob from the aggregator and verify the bytes match the source?
- Is the publisher and aggregator pair correct for the chosen network (testnet or mainnet)?
- If a Move Object commits the blob id, is that path tested with at least one positive test?
- Was the lifetime decision (epochs vs permanent) explicitly stated, not silently defaulted?
- If the data is sensitive, is encryption actually performed client-side, with a documented key plan?
- Is the integration code not just calling `store` and forgetting? Read-back must be in the code path.

If any answer is no, the skill reports the gap and works through it before claiming the integration is complete.

## References

On-demand references (load when relevant to the user's question):

- `references/walrus-quickstart.md`: Minimal upload and retrieve recipes for HTTP publisher, CLI, and TS SDK.
- `references/walrus-pitfalls.md`: Lifetime expiry, encryption, public endpoint reliability, network mismatches, WAL token balance.
- `references/walrus-move-commit.md`: Pattern for committing a `blobId` on chain inside a Move Object.
- `references/seal-encryption.md`: Seal decentralized encryption for access-controlled Walrus blobs.

Related skills:

- `walrus-sites`: Host static sites (SPAs, landing pages) directly on Walrus.
- `seal-access-control`: Full Seal encryption integration (Move policy + TS SDK) for access-gated Walrus blobs.
- `build-ai-agent`: For AI agent memory on Walrus, see MemWal (`@mysten-incubation/memwal`), which stores agent context as Walrus blobs with Seal encryption. Docs: https://github.com/MystenLabs/MemWal

Knowledge docs (load when scope expands beyond what is in references):

- `skills/data/sui-knowledge/sponsor-docs/walrus.md`: Concepts, key terms, deeper integration notes.

## Use in your agent

- Claude Code: `claude "/suiper:walrus-storage <your message>"`
- Codex: `codex "/walrus-storage <your message>"`
- Cursor: paste a chat message that includes a phrase like "store files on Walrus", or load `~/.cursor/rules/walrus-storage.mdc` and reference it.

If you activated this and the user actually wants something else, consult `skills/SKILL_ROUTER.md` and hand off.