Chain 138 Open Snap

Official Snap ID: npm:chain138-open-snap

A MetaMask Snap for Chain 138 — DeFi Oracle Meta Mainnet (EVM, chain ID 138 / 0x8a). It uses only open Snap permissions, so users can install it from npm without a MetaMask allowlist.

Why this package

| Goal | How this Snap handles it | |------|---------------------------| | Explain the network | Home page shows RPC, block explorer, and a link to the canonical token list (with logoURIs suited to wallets). | | Context on activity | Transaction and signature insights when you interact with dApps (with optional site origin where the manifest allows it). | | Lightweight reminders | Weekly cron notification nudging you to refresh token metadata awareness (optional dismiss via preferences). | | No extra trust surface | Does not use endowment:network-access or endowment:rpc — the Snap does not fetch arbitrary URLs or expose a custom JSON-RPC API.

What users see

After installation, open MetaMask → Snaps → Chain 138 Open for:

• Network name, public RPC, and explorer links
• Token list URL: https://explorer.d-bis.org/api/config/token-list
• Live eth_chainId / block readout when the wallet RPC matches Chain 138
• Transaction and signature panels for review flows

Default public RPC referenced in the UI: https://rpc-http-pub.d-bis.org (adjust in-wallet if you use another endpoint).

Permissions (all open / allowlist-free)

• Home page, Ethereum provider (read-only wallet RPC helpers in-app)
• Transaction insight and signature insight (with origin as permitted by MetaMask)
• Lifecycle hooks (install / update / start)
• Cronjob (weekly reminder)
• Dialog, notifications, preferences, managed state (lightweight counters / install metadata)

Install (dApps or DevTools console)

await ethereum.request({
  method: 'wallet_requestSnaps',
  params: { 'npm:chain138-open-snap': {} },
});

Requires a MetaMask build that supports Snaps (e.g. Flask during development — follow current MetaMask docs).

Develop locally

npm install
npm run build
npm run serve

Point MetaMask at the local Snap URL from mm-snap serve (see MetaMask Snaps developer docs).

CI-style check (production dependencies only):

npm run verify   # npm audit --omit=dev && npm run build

A full npm audit may still report low-severity items under the Snaps CLI toolchain; bn.js is pinned via overrides.

npm + nvm (prefix warning)

scripts/deployment/publish-chain138-open-snap.sh in the monorepo unsets npm_config_prefix and runs nvm use --delete-prefix when NVM_DIR is set. If warnings persist, remove a stray prefix= from ~/.npmrc.

Publish to npm

From the proxmox repo root (recommended — uses an isolated npm userconfig so tokens are not written into the repo):

./scripts/deployment/publish-chain138-open-snap.sh

Or from this package directory after npm login:

npm install
npm publish

prepack runs npm run build so dist/ and snap.manifest.json shasum match the tarball.

2FA / tokens: Publishing may require a granular token with publish rights and 2FA bypass for automation, or npm publish --otp=…. See npm’s token documentation.

Version bumps: Change version in package.json and in source (SNAP_VERSION in src/index.tsx when bumped), run npm run build, then publish.

Repository

Canonical source: Defi-Oracle-Tooling/chain138-snap-minimal.

The same package is also vendored under bis-innovations/proxmox at metamask-integration/chain138-snap-minimal so the monorepo can run scripts/deployment/publish-chain138-open-snap.sh and keep explorer docs in one tree. Prefer the standalone repo for issues and PRs focused on the Snap only.

License

(MIT-0 OR Apache-2.0) — dual-license, same pattern as metamask-integration/chain138-snap/.