Integration Checklist

Integration checklist, UX patterns, and rollout guidance for product teams shipping MOSS in production. Optimized for product, engineering, and security leads working together before implementation kickoff.

What This Checklist Covers

Area	What to decide
UX flows	Connect/auth, signing prompts, background actions, cancellation handling, fallback states.
Data + permissions model	Session key scope, spend limits, contract allowlists, expiry windows, revocation defaults.
Timeline + rollout	Sandbox tests, pilot cohort, success criteria, rollback plan, release gates.
Gas strategy	Default user-paid gas in ETH or enabled stablecoins; optional partner sponsorship via sponsorUrl + sponsorMode + sponsorToken.
Security + compliance	Threat model, backend verification, key handling, logging controls, audit artifacts.

Gas Abstraction Options

Gas is abstracted through the relay and smart account infrastructure. Users can pay gas with ETH or enabled stablecoins (currently USDm and USDT0). Recommended default: sponsorMode: 'app-only' and sponsorToken: 'native'. Use explicit when you only want to sponsor selected app actions.

Mode	Who pays	Who controls logic
User-paid gas (default)	User (ETH or enabled stablecoins)	MegaETH relay
Partner sponsorship (app-only default)	Developer	Sponsor endpoint + mode controls
Partner sponsorship (explicit / everything)	Developer	Per-request or broad sponsorship policy

Integration Checklist

1. UX and Product Flows

• Define first-run journey: connect, sign, first transaction.
• Define cancellation behavior for all wallet prompts.
• Define silent/background operation boundaries and user consent language.
• Define fallback UX for disconnected state and RPC/network errors.

2. Permissions and Data Model

• Choose strict grantPermissions defaults (every calls[] entry includes both to and signature, low spend caps, short expiry).
• Decide session duration and automatic revocation policy.
• Define required on-chain contracts and method allowlists.
• Decide what wallet state is persisted client-side vs server-side.

3. Gas + Funding Strategy

• Choose primary path: user-paid token gas or partner sponsorship (app-only, explicit, everything).
• Define sponsorship budget ceilings and alert thresholds.
• If using external paymaster, define rate limits and contract policy checks.
• Confirm user messaging for "who pays gas" across all key flows.

4. Security and Compliance

• Use server-side ownership verification for auth/account linking.
• Confirm no private keys/session secrets are persisted in frontend storage.
• Validate logging policy excludes sensitive payloads.
• Create incident runbook for permission abuse or sponsorship drain attempts.

5. Launch Plan

• Stage in test environment, then run limited pilot rollout.
• Define launch KPIs (conversion, success rate, median completion time).
• Add monitoring for auth, transaction outcomes, and sponsorship spend.
• Prepare rollback criteria and decision owner.

Related

• Quickstart — install through first transaction.
• Paymaster Setup — implementation guide for built-in and external sponsorship paths.
• Best Practices — security patterns and permission defaults for production.

For scoping conversations: [email protected].