business-blueprint

Comprehensive business-logic blueprint for SaaS, ERP, e-commerce, and marketplace applications. Walks through every domain (auth, billing, multi-tenancy, inventory, audit, compliance, etc.), surfaces

SKILL.md

GitHub

/business-blueprint

A structured walkthrough of business logic for the project type the user is building. Output is a personalized blueprint — the relevant domains for their app, the edge cases that matter, and a prioritized build plan.

When to use

  • Starting a new SaaS / ERP / e-commerce / marketplace / fintech project — before committing to an architecture.
  • Auditing an existing project against the full set of real-world concerns.
  • Onboarding to a domain you haven't built before and want a checklist of what to think about.
  • Preparing for a Series A / SOC 2 / enterprise customer review.

Operating method

1. Lock down the project type and context

Ask, in one round:

  • Project type: SaaS / ERP / e-commerce / marketplace / fintech / internal tool / something else.
  • Customer: B2C / SMB B2B / mid-market B2B / enterprise B2B / government / regulated industry.
  • Sales motion: self-serve / freemium / sales-led / hybrid.
  • Monetization: subscription / usage / transaction fee / one-time / hybrid.
  • Jurisdictions (where customers and the business are): US / EU / UK / India / etc.
  • Stage: pre-launch / early users / scaling / mature.
  • Constraints: must-self-host, no-third-party-data, single-region, etc.

Don't blueprint without these. Domain ambiguity makes for irrelevant blueprints.

2. Walk the domain checklist for the project type

Different project types have different "must-have at v1" lists. Pick the matching section below.

SaaS blueprint

Identity & access

  • Auth methods: password + magic link minimum; OAuth (Google/GitHub) for self-serve; SAML SSO for enterprise tier.
  • MFA: TOTP + WebAuthn. Avoid SMS for high-value accounts.
  • Roles: Owner > Admin > Member > Viewer (B2B default). Customize per domain.
  • Permission model: role-based at v1. ABAC if resources need fine-grained ownership.
  • Session: refresh tokens with rotation; idle timeout per security tier.
  • Account merging: design how to handle "user signs up Google and SAML with same email."
  • Account recovery: backup admin, recovery codes, support escalation path.

Multi-tenancy

  • Isolation: shared DB + tenant_id (default for < 10K tenants). DB-per-tenant for enterprise/regulated.
  • Tenant context: every query filters tenant_id; wrap DB layer.
  • Cross-tenant tests: integration test that runs as A and tries B's IDs — should always 404.
  • Tenant switching UI for multi-workspace users.
  • Tenant export (GDPR, portability).
  • Tenant deletion (cascade, retention).

Subscription billing

  • Stripe Billing / Recurly / Paddle / Chargebee — pick one, don't roll your own.
  • Plan structure: tiered + usage hybrid is most common (Stripe pricing model).
  • Trial: 14-day free trial without credit card is the SMB default; 30-day with-card for enterprise.
  • Upgrade: immediate, prorate. Downgrade: end-of-period (default) or immediate with refund.
  • Failed payment: Stripe Smart Retries default (4 retries / 15 days). Email cadence d1/d3/d7. Grace period before suspend.
  • Dunning: in-app banner + email + customer portal for self-rescue.
  • Cancel: cancel-at-period-end vs immediate. Retention offer at cancel time (downgrade, pause, discount).
  • Refunds: partial vs full, time window, who can authorize, audit trail.
  • Coupons: stacking rules, expiration, code-vs-link, fraud prevention.
  • Tax: Stripe Tax / Avalara — never hand-roll VAT/GST/sales-tax.
  • Invoices: sequential, immutable, PDF retention, e-invoicing for EU.

Onboarding

  • Trial: minimize time-to-value (TTV). One-step signup if possible.
  • Activation event: define what "activated" means (first invite sent? first project created? first payment?).
  • Onboarding checklist UI for SaaS.
  • Empty states that guide first action.
  • Sample data option for demos.

Notifications

  • Channels: in-app, email, SMS, push, webhook, Slack.
  • Per-user per-category preferences.
  • Digest mode for low-priority items.
  • One-click unsubscribe + suppression list.
  • Localization (timezone, language).
  • Quiet hours / do-not-disturb.

Webhooks (outgoing for integrators)

  • HMAC signing.
  • Retry with exponential backoff + dead-letter.
  • Stable event IDs for dedupe.
  • No ordering guarantees.
  • Schema versioning + sunset policy.

API

  • Versioning (URL or header).
  • Idempotency-Key header on every state change.
  • Cursor-based pagination.
  • Rate limits per-key + per-tenant.
  • Stable error codes alongside human messages.

Audit & compliance

  • Audit log on every state change to regulated entities.
  • Append-only, retention by data class.
  • SOC 2 readiness: access controls, monitoring, change management, vendor management.
  • GDPR: DSAR endpoint, right-to-erasure (cascade including backups), DPA with sub-processors.

Account lifecycle

  • Trial → paid conversion.
  • Active → past_due → suspended → cancelled.
  • Cancelled → reactivation window (typically 30 days).
  • Permanent deletion after retention.

ERP blueprint

Financial

  • Chart of accounts (5- or 6-digit hierarchy: assets, liabilities, equity, revenue, expense).
  • Double-entry posting: every transaction has matching debits and credits.
  • Period close: monthly + annual; lock once closed; adjustments via journal entries.
  • Multi-currency: functional currency vs presentation currency. FX rate table. Realized vs unrealized FX gains/losses.
  • AR (accounts receivable): invoice → payment → reconciliation; aging buckets (30/60/90+).
  • AP (accounts payable): PO → GRN (goods received note) → invoice → payment → 3-way match.
  • GL (general ledger): every transaction posts here; trial balance must balance.
  • Depreciation: straight-line / declining-balance / units-of-production. Recurring monthly entry.
  • Tax: VAT/GST per line item, configurable per jurisdiction.
  • Bank reconciliation: import statement → match transactions.

Inventory

  • Stock levels: on-hand, reserved, allocated, available = on_hand − reserved − allocated.
  • Valuation: FIFO / LIFO / average cost / specific identification. Pick per business; tax implications.
  • Multi-warehouse: stock per location; transfers; in-transit.
  • Lot / serial tracking for regulated industries (food, pharma, electronics).
  • Cycle counting: scheduled partial inventory checks; variance tracking.
  • Reorder points: min stock + reorder qty per SKU. Auto-PR when triggered.

Procurement

  • Workflow: PR (purchase requisition) → PO (purchase order) → GRN (goods received note) → invoice → payment.
  • 3-way match: PO + GRN + invoice quantities and prices must agree.
  • Vendor management: master data, terms, ratings.
  • Approval workflows: thresholds by amount + role.
  • Blanket POs / contracts.

Sales

  • Workflow: quote → order → fulfillment → invoice → payment.
  • Credit limits per customer; block orders that exceed.
  • Returns / RMAs: link to original order, restock or scrap, refund or credit memo.
  • Drop-ship vs warehouse fulfillment.

Manufacturing (if applicable)

  • BOM (bill of materials): components per finished good; multi-level.
  • MRP (material requirements planning): demand → required components → POs.
  • Work orders: production schedule, routings, capacity.
  • Scrap / rework tracking.

HR / payroll (if applicable)

  • Employee master data, org structure, manager hierarchy.
  • Time tracking: timesheets, approvals.
  • Payroll: gross → deductions → net. Per-jurisdiction tax + benefits.
  • Leave management: accrual, balance, requests.
  • Performance reviews + onboarding/offboarding workflows.

Compliance

  • SOX (US public companies): segregation of duties (no one approves their own POs), audit trail, change management.
  • Approval matrices: by amount, by role, by department.
  • Audit log: append-only, queryable, retained 7+ years.

E-commerce blueprint

Catalog

  • Products + variants (size, color, material).
  • SKUs unique per merchant.
  • Bundle products, subscription products, digital goods, services.
  • Inventory sync to fulfillment systems.

Cart & checkout

  • Cart abandonment recovery (email at 1h / 24h / 72h).
  • Guest checkout vs account-required.
  • Shipping calculator (rate per zone + weight or flat).
  • Tax: Stripe Tax / Avalara / TaxJar.
  • Address validation.
  • Multi-payment-method: card, wallet (Apple/Google Pay), BNPL (Klarna/Afterpay), bank transfer (B2B).
  • Idempotent checkout: re-submitting must not double-charge.
  • 3DS / SCA for EU/UK.

Order management

  • Order states: pending → paid → fulfilled → completed. Or cancelled / refunded / disputed.
  • Inventory hold at order placement; release on cancel.
  • Partial fulfillment (some items ship now, others later).
  • Backorders.
  • Order edits (price adjust, item swap) — track who, when, what.

Returns / RMA

  • Return window (typically 14–30 days; longer is friendlier).
  • Refund vs store credit vs exchange.
  • Restock vs scrap.
  • Return shipping label generation.
  • Dispute / chargeback workflow.

Fraud

  • Risk scoring (Stripe Radar, Sift, Signifyd).
  • Velocity rules (multiple orders to new shipping address, mismatched billing/shipping).
  • Manual review queue.
  • Blocklist (email, IP, card).

Marketplace-specific (if applicable)

  • Seller onboarding + KYC.
  • Connected accounts (Stripe Connect Express/Custom).
  • Split payments + platform fee.
  • Payouts schedule + holds for first-time sellers.
  • Seller-side dashboard.
  • Dispute escalation between buyer/seller/platform.

Marketplace blueprint

Add to e-commerce blueprint:

  • KYC/AML for sellers (Stripe Identity, Persona, Sumsub).
  • Transaction monitoring for money-laundering signals.
  • Dual-side reviews (buyer rates seller; seller rates buyer).
  • Escrow / hold periods (release funds N days after delivery).
  • Dispute resolution between buyers and sellers.
  • Tax form generation (1099-K in US for sellers above threshold).

Fintech blueprint

Add stricter versions of:

  • KYC/AML at onboarding + transaction monitoring.
  • Sanctions screening (OFAC, EU, UN lists).
  • Reg-specific compliance (PSD2 SCA, GDPR, PCI-DSS Level 1).
  • Audit log retention 7+ years; immutable + append-only ledger.
  • Reconciliation jobs that run nightly and alert on mismatches.
  • Reserves and capital requirements per regulator.
  • Disaster recovery RTO/RPO measured in minutes.

Full-stack web app (no specific business domain)

Use SaaS blueprint as default; trim sections that don't apply.

3. Identify what's missing

Compare the user's current project against the relevant blueprint. Mark each item as:

  • Done — already implemented well.
  • Partial — exists but has gaps.
  • Missing — not started; risk level depending on stage.
  • N/A — doesn't apply to this project.

4. Prioritize by stage

  • Pre-launch — auth, basic billing, 1 plan, audit log, terms/privacy. Don't over-engineer; 80% of mature-SaaS features are post-PMF.
  • Early users (< 100 paying) — solid billing (failed-payment retries, dunning), one good notification channel, GDPR basics.
  • Scaling (100–10K paying) — multi-tier plans, SAML SSO for enterprise tier, robust webhooks, audit log, SOC 2 prep.
  • Mature — multi-currency, multi-region, advanced RBAC, public API w/ versioning, full SOC 2 + GDPR + region-specific compliance.

Don't recommend mature-stage features to a pre-launch project. Stage matters more than feature completeness.

5. Save the blueprint

Write the result to .claude/memory/project/business-blueprint.md so future sessions reference it. Add to MEMORY.md.

Output format

## Project context
- Type: <saas/erp/...>
- Customer: <segment>
- Stage: <pre-launch/early/scaling/mature>
- Jurisdictions: <list>

## Audit
| Domain | Status | Notes |
|---|---|---|
| Auth + MFA | Done | TOTP only; consider WebAuthn |
| Multi-tenancy | Partial | tenant_id filter present; cross-tenant test missing |
| Billing — failed payment | Missing | High risk for SaaS — implement before scaling |
| Audit log | Missing | Required pre-SOC-2 |
| …

## Top 5 priorities for your stage
1. <highest impact>
2. …

## Build plan
- Now (this sprint): <items>
- Soon (next 2 sprints): <items>
- Later (post-PMF / SOC 2 prep): <items>
- Maybe never: <items that don't fit your context>

## Open questions for you
1. …

Boundaries

  • Don't recommend mature-stage complexity to a pre-launch project.
  • Don't invent in well-trodden domains (billing, auth, search) — point at Stripe/Auth0/Algolia patterns.
  • Don't overlook jurisdiction-specific compliance.
  • Don't write the actual code from this skill; this is the plan. Implementation happens in subsequent sessions, agent by agent.
  • Always cite where a recommendation comes from (Stripe Billing docs, Linear engineering blog, etc.) when borrowing patterns.