16 KiB
16 KiB
title, type, status, created, updated
| title | type | status | created | updated |
|---|---|---|---|---|
| Payment Gateway Integration PRD | prd | draft | 2025-11-04 | 2025-11-04 |
Product Requirements Document: Payment Gateway Integration
Objectives
Primary Objectives
-
Enable Real-time Online Payment Processing
- Goal: Allow customers to complete purchases instantly without manual invoice processing
- Measure: Checkout conversion rate and average checkout time
- Target: 75% conversion rate (up from 55%), average checkout time under 45 seconds
- Timeline: Launch by Q2 2026, achieve targets within 3 months post-launch
- Why it matters: Eliminates primary source of cart abandonment (45% currently) and recovers $1.8M in lost annual revenue
-
Reduce Operational Costs and Manual Work
- Goal: Automate payment processing and reconciliation to eliminate manual labor
- Measure: Hours spent on manual payment processing and reconciliation
- Target: Reduce from 20 hours/week to 4 hours/week (80% reduction)
- Timeline: Immediate upon launch
- Why it matters: Saves $100K annually in labor costs, allows sales/finance teams to focus on high-value work
-
Improve Customer Satisfaction with Modern Checkout
- Goal: Provide seamless, secure checkout experience matching major e-commerce sites
- Measure: NPS score for checkout experience and payment-related support tickets
- Target: NPS 50+ (up from 35), reduce payment support tickets by 50%
- Timeline: Measure within 30 days post-launch
- Why it matters: Customer satisfaction drives repeat purchases and positive word-of-mouth
Secondary Objectives
- Enable subscription and recurring billing capabilities (Phase 2 - deferred 6-12 months)
- Support international currencies and payment methods (Phase 2 - market dependent)
Success Criteria
Launch Criteria (Must-Have)
Functional Completeness
- Process 100 test transactions with 0% failure rate
- Support card payments (Visa, MC, Amex, Discover) and digital wallets (Apple Pay, Google Pay)
- One-click checkout functional for returning customers with saved payment methods
- Integration with Salesforce CRM and QuickBooks accounting complete
- Email confirmations sent within 30 seconds of successful payment
Quality Standards
- Payment processing time <3 seconds at 95th percentile
- Checkout page load time <2 seconds
- PCI DSS SAQ-A compliance validation complete
- Security audit passed with zero critical vulnerabilities
- Mobile-responsive checkout tested on iOS and Android
Operational Readiness
- Stripe integration monitoring and alerting configured
- Webhook processing with retry logic implemented
- Runbooks for common payment issues created
- Support team trained on new checkout flow and troubleshooting
- Customer-facing documentation published
Success Metrics (Post-Launch)
Adoption Metrics (30 days)
- Transaction volume: 0 → 1,000+ online transactions processed
- Saved payment adoption: 60% of customers save payment method on first use
Engagement Metrics (30 days)
- Checkout conversion: 55% → 75% (reduce abandonment 45% → 25%)
- Average checkout time: N/A → 45 seconds (90th percentile)
Business Metrics (90 days)
- Revenue recovery: $150K+ in previously abandoned cart revenue
- Operational cost reduction: 80% reduction in manual payment processing time
- Customer satisfaction: NPS 35 → 50+ for checkout experience
Quality Metrics (30 days)
- Payment success rate: 98%+ of initiated transactions complete successfully
- System uptime: 99.9%+ (max 45 minutes downtime per month)
- Support ticket reduction: 50% fewer payment-related inquiries
Functional Requirements
FR1: Credit/Debit Card Payment Processing
Description: Process credit and debit card payments securely in real-time with instant confirmation
User Story: As an online shopper, I want to pay with my credit/debit card directly on the checkout page, so that I can complete my purchase immediately without waiting for invoices
Inputs:
- Card number, expiration date, CVV (via Stripe Elements)
- Billing address
- Purchase amount and order details
- Customer email
Outputs:
- Payment confirmation with transaction ID
- Order receipt via email
- Updated order status in CRM
Business Rules:
- Accept Visa, Mastercard, American Express, Discover
- Require CVV for all transactions (fraud prevention)
- Maximum transaction amount: $10,000 (fraud threshold)
- Minimum transaction amount: $1.00
Acceptance Criteria:
- Given valid card details, when customer submits payment, then transaction processes in <3 seconds
- Given invalid card number, when customer submits, then clear error message displays before submission
- Given successful payment, when transaction completes, then confirmation email sent within 30 seconds
- Given payment failure, when Stripe returns error, then user-friendly message explains issue and suggests resolution
Priority: Must Have
Dependencies: Stripe API integration, email service (SendGrid)
FR2: Digital Wallet Support (Apple Pay / Google Pay)
Description: Enable payment via Apple Pay and Google Pay for faster mobile checkout
User Story: As a mobile shopper, I want to pay with Apple Pay/Google Pay, so that I can checkout with a single tap using my saved payment method
Inputs:
- Apple Pay/Google Pay token
- Purchase amount
- Shipping address (from wallet if available)
Outputs:
- Payment confirmation
- Order receipt
Business Rules:
- Available only on supported browsers/devices
- Gracefully degrade to card entry if wallet unavailable
- Auto-fill shipping address from wallet when possible
Acceptance Criteria:
- Given iPhone with Apple Pay, when user selects Apple Pay, then payment completes with Face ID/Touch ID
- Given Android with Google Pay, when user selects Google Pay, then payment completes with fingerprint/PIN
- Given wallet payment, when user confirms, then checkout completes in <10 seconds total
- Given unsupported browser, when checkout loads, then wallet buttons hidden and card entry shown
Priority: Should Have
Dependencies: Stripe Payment Request API, HTTPS (required for Apple Pay)
FR3: Saved Payment Methods (One-Click Checkout)
Description: Allow customers to securely save payment methods for faster future checkouts
User Story: As a returning customer, I want to save my payment method, so that I can checkout with one click on future purchases without re-entering my card
Inputs:
- "Save payment method" checkbox selection
- Customer account (must be logged in)
- Payment method details (tokenized by Stripe)
Outputs:
- Payment method saved to customer account (Stripe token stored)
- Display last 4 digits and card brand in account
Business Rules:
- Maximum 5 saved payment methods per customer
- Must be logged in to save payment method
- Can set one method as default
- Can delete saved methods anytime
Acceptance Criteria:
- Given logged-in customer, when they check "save payment method", then method saved after successful payment
- Given returning customer, when they view saved methods, then see last 4 digits and expiration date (not full number)
- Given saved payment method, when customer selects it at checkout, then auto-fills payment form
- Given multiple saved methods, when customer sets default, then it pre-selects at checkout
Priority: Must Have
Dependencies: FR1, user authentication, Stripe payment methods API
FR4: CRM Integration (Salesforce)
Description: Automatically sync payment transactions and customer payment methods with Salesforce CRM
User Story: As a sales rep, I want payment information automatically updated in Salesforce, so that I have complete customer transaction history without manual entry
Inputs:
- Successful payment transaction
- Customer email (matches Salesforce contact)
- Order details
Outputs:
- Salesforce opportunity updated to "Closed Won"
- Transaction record created in Salesforce
- Customer payment method status updated
Business Rules:
- Match customers by email address
- Create new contact if email not found
- Update opportunity within 5 minutes of payment
- Store only last 4 digits of card in Salesforce
Acceptance Criteria:
- Given successful payment, when transaction completes, then Salesforce opportunity updated within 5 minutes
- Given new customer, when payment completes, then new Salesforce contact created
- Given existing customer, when payment completes, then transaction added to existing contact
- Given CRM sync failure, when Stripe payment succeeds, then retry CRM update 3 times with exponential backoff
Priority: Must Have
Dependencies: Salesforce API access, webhook processing
FR5: Accounting Integration (QuickBooks)
Description: Automatically post successful transactions to QuickBooks for revenue recognition and reconciliation
User Story: As a finance team member, I want transactions automatically posted to QuickBooks, so that I don't spend 20 hours/week on manual data entry and reconciliation
Inputs:
- Successful payment transaction
- Customer details
- Product/service purchased
- Payment amount and fees
Outputs:
- QuickBooks invoice created and marked paid
- Revenue recognized in correct account
- Stripe fees recorded as expense
Business Rules:
- Post within 1 hour of successful payment
- Separate revenue and Stripe fees into different accounts
- Match customer to existing QuickBooks customer or create new
- Handle partial refunds correctly
Acceptance Criteria:
- Given successful payment, when transaction completes, then QuickBooks invoice posted within 1 hour
- Given $100 transaction with $3.20 Stripe fee, when posted, then $100 revenue and $3.20 fee expense recorded
- Given full refund, when processed, then QuickBooks invoice voided
- Given partial refund, when processed, then credit memo created for refund amount
Priority: Should Have
Dependencies: QuickBooks API integration, webhook processing
Non-Functional Requirements
NFR1: Performance
Response Time:
- Payment API calls: <500ms at 95th percentile
- Checkout page load: <2 seconds
- Payment processing (submit to confirmation): <3 seconds at 95th percentile
Throughput:
- Support 1,000 concurrent users during peak sales
- Process 150 transactions per hour during peak load
- Handle webhook processing for 200 events/hour
Testing Requirements:
- Load test with 1,000 concurrent users for 1 hour
- Stress test to 2x expected peak load
NFR2: Security
Authentication/Authorization:
- API keys stored in environment variables (never in code)
- Use Stripe API key with minimum required permissions
- Session-based auth for saved payment methods (must be logged in)
Data Protection:
- Never store raw credit card numbers (use Stripe tokens only)
- All payment data transmitted via TLS 1.3
- PCI DSS SAQ-A compliance (tokenization model)
- 3D Secure 2.0 enabled for high-risk transactions
Compliance:
- Complete PCI DSS SAQ-A questionnaire annually
- GDPR compliant (support payment method deletion requests)
- SOC 2 compliant webhook processing
Security Testing:
- Pass OWASP Top 10 security audit
- Penetration testing before launch
- Annual security review
NFR3: Reliability
Availability:
- 99.9% uptime SLA (maximum 45 minutes downtime per month)
- Graceful degradation if Stripe API unavailable
Error Handling:
- Retry transient Stripe API failures (3 retries with exponential backoff)
- Display user-friendly error messages (never show raw API errors)
- Log all errors for debugging and alerting
Data Integrity:
- Idempotent payment processing (prevent duplicate charges)
- Webhook processing with deduplication
- Transaction logging for audit trail
Monitoring & Alerting:
- Alert if payment success rate <95% over 15-minute window
- Alert if average response time >5 seconds
- Alert on any Stripe webhook failures
- Daily reconciliation report comparing Stripe transactions to database
NFR4: Usability
Checkout Experience:
- Maximum 4 steps to complete checkout (cart → info → payment → confirm)
- Guest checkout option (no account required)
- Auto-fill billing address from shipping address
- Clear progress indicator showing checkout steps
Mobile Experience:
- Fully responsive design (mobile, tablet, desktop)
- Digital wallet buttons prominent on mobile
- Card input fields optimized for mobile keyboards
- Minimum tap target size 44x44 pixels
Accessibility:
- WCAG 2.1 AA compliance
- Keyboard navigation for all form fields
- Screen reader compatible
- Clear focus indicators
Error Messages:
- Specific, actionable error messages ("Card declined - try different card" not "Error 402")
- Inline validation (show errors immediately, not after submit)
- Error summary at top of form
Constraints
Technical Constraints:
- Must use Stripe as payment processor (existing vendor relationship)
- Must integrate with existing Salesforce CRM instance
- Must use existing QuickBooks accounting system
- Frontend must support IE11+ (legacy enterprise requirement)
Business Constraints:
- Launch deadline: June 30, 2026 (hard deadline for fiscal year)
- Budget: $150K total (development + first year transaction fees)
- Transaction fee budget: 3% of GMV (already factored into pricing)
Regulatory Constraints:
- PCI DSS compliance required (using SAQ-A)
- GDPR compliance (right to deletion of payment data)
- State sales tax collection required (out of scope for payment integration)
Resource Constraints:
- 2 frontend engineers, 1 backend engineer, 1 QA engineer
- 16-week development timeline (4 sprints of 4 weeks each)
- No dedicated DevOps engineer (must use existing infrastructure)
Assumptions
User Assumptions:
- 60% of users will access from mobile devices
- 70% of users will save payment method if offered
- Users have modern browsers (Chrome, Safari, Firefox, Edge - last 2 versions)
- Average transaction value: $275
Technical Assumptions:
- Stripe API maintains 99.99% uptime (historical average)
- Stripe API remains backward compatible (no breaking changes)
- Webhooks delivered within 5 minutes (Stripe SLA)
- Current infrastructure can handle 10x transaction volume growth
Business Assumptions:
- Transaction volume grows from 1,000/month to 5,000/month within 6 months
- Cart abandonment reduces from 45% to 25% after launch
- Customers willing to pay current pricing plus transaction fees
- Sales team capacity sufficient for increased order volume
Out of Scope
Features Explicitly Excluded:
- Cryptocurrency payments (deferred to Phase 3, market still nascent)
- Buy now, pay later (BNPL) options like Klarna/Affirm (Phase 2, evaluate demand)
- Subscription and recurring billing (Phase 2, not needed for MVP)
- International currency support beyond USD (Phase 2, market dependent)
- ACH/bank transfer payments (low demand, complex compliance)
- Gift cards and store credit (Phase 3 feature)
Deferred to Future Phases:
- Advanced fraud detection rules customization (use Stripe Radar defaults for MVP)
- Multi-currency pricing and display (Phase 2, after international expansion)
- Invoice payment portal for net-30 terms (separate project)
- Payment plan/installment options (Phase 2 after BNPL evaluation)
Platforms Not Supported:
- Internet Explorer 10 and older (< 2% traffic, not worth compatibility effort)
- Native mobile apps (web-only for MVP, may build apps in Phase 3)
- In-person/POS payments (separate product line, not e-commerce focus)