Software delivery, by the numbers
01
- software products shipped
- 100+
02
- average time to first production release
- 12 weeks
03
- rated by clients on Clutch
- 4.9/5
04
- years delivering software for established businesses
- 9+
RaftLabs integrates payment gateways into custom software - web apps, mobile apps, SaaS platforms, and B2B portals. Not copy-pasting a Stripe JS snippet. The work is the billing logic: subscription states, refund workflows, webhook reliability, and revenue splits that hold when your transaction volume grows.
Most payment bugs aren't gateway bugs. They're logic bugs: a refund that partially updates a subscription, a webhook that fires twice and charges a customer twice, a marketplace that settles the wrong amount to a seller. The integration has to model your billing correctly or the failures compound.
According to McKinsey's 2025 Global Payments Report, global payments revenues reached $2.5 trillion last year and are forecast to surpass $3 trillion by 2029 - a market growing at 4% annually even in a slow year. For software teams, that growth lands as pressure: buyers expect frictionless checkout, subscription billing, and multi-currency support as a baseline, not a premium feature.
Capabilities
Payment integration services
Stripe Checkout, Stripe Elements, and Stripe Billing configured for your product's pricing model. Subscription plans, free trials, proration on plan changes, usage-based billing via Stripe Metered Billing, and the customer portal for self-serve plan management. Stripe Connect for marketplace platforms paying out to multiple sellers. Webhook handling for all critical Stripe events - payment failures, subscription renewals, disputes, and refunds - with idempotency keys so double-firing doesn't produce double charges.
02Subscription billing systems
Subscription logic built on top of your chosen gateway. Plan tiers with monthly and annual options, trial periods with conversion tracking, mid-cycle plan upgrades and downgrades with proration calculated correctly, and dunning flows for failed renewals. Customer billing portal so users can manage their own subscription without contacting support. The logic that looks simple on paper but breaks in edge cases - mid-trial upgrades, annual plans on monthly billing cycles, coupons applied to recurring charges - handled before it hits production.
03Marketplace payment splitting
Payment flows for platforms where revenue goes to multiple parties. Stripe Connect, PayPal for Marketplaces, or Braintree Marketplace configured for your split model. Funds held in escrow until fulfilment conditions are met, then released to sellers on your payout schedule. Platform fee deducted before seller payout. Seller onboarding flow with identity verification (KYC) required by the gateway. Seller dashboard showing earnings, payout history, and payout schedule.
04PayPal and Braintree integration
PayPal Checkout and Braintree Drop-in UI for platforms where buyer trust and PayPal wallet acceptance matter. Braintree's vaulted card storage for repeat purchases without re-entering card details. PayPal's buyer protection messaging in checkout for B2C platforms where trust signals affect conversion. Recurring billing via Braintree's subscription API for SaaS products targeting markets where PayPal is the preferred payment method.
05Multi-currency and international payments
Gateway configuration for accepting payments in multiple currencies. Currency detection by buyer location, price display in local currency, settlement in your base currency. Stripe's multi-currency presentment and PayPal's multi-currency support configured with the right decimal handling per currency. Tax calculation integration (Stripe Tax or TaxJar) for platforms selling across tax jurisdictions.
06Webhook handling and payment reconciliation
Webhook endpoints built with proper signature verification, idempotency, and retry logic. Events processed in order for subscriptions - payment intent created, payment succeeded, invoice finalized - so your application state matches the gateway state. Reconciliation logging so you can audit any transaction and confirm your records match the gateway's. Alerting for webhook delivery failures and payment events that require manual review.
Moving from one payment gateway to another without interrupting active subscriptions. Token migration from Braintree, Adyen, or a legacy direct integration to Stripe. Subscription state mapping so active subscribers carry over without being charged twice or losing their billing cycle. Cutover executed during a low-traffic window with a fallback plan if the migration produces unexpected failures.
Why us
Why teams choose RaftLabs
01Senior engineers build what they scope
The engineers who assess your billing problem also build the integration. No bait-and-switch, no offshore handoff after the contract is signed. The team you meet in week 1 ships in week 12.
02Fixed price before development starts
We scope the billing model, calculate the cost, and lock it in writing before any development starts. A scope change is a change request: priced, agreed, or dropped. It never absorbs into the project and appears on the final invoice.
039 years and 100+ products shipped
Clients include Vodafone, T-Mobile, Aldi, Nike, Cisco, and Lockheed Martin. Track record across SaaS billing, marketplace payment splits, subscription platforms, and multi-currency ecommerce across healthcare, fintech, logistics, and hospitality.
04Compliance built in from the start
PCI DSS, GDPR, HIPAA - compliance requirements are scoped in week 1, not retrofitted before launch. We build integrations that follow tokenisation best practices so your application stays out of PCI scope. We have shipped HIPAA-compliant billing systems for US healthcare clients and GDPR-compliant payment flows for European markets.
Process
How payment integrations are built
Five steps from initial billing requirements to a production payment system with documented edge-case handling.
- Week 1
01Billing requirements and gateway selection
We document your exact billing model - one-time charges, subscriptions, usage-based billing, marketplace splits, or a combination. We review your geography, target customer segments, and existing tech stack, then recommend the right gateway or gateway combination. Gateway selection at this stage is cheaper than migrating six months later.
- Week 1
02Integration architecture
Before writing integration code, we map the full payment flow: checkout entry points, gateway API calls, webhook events and handlers, database state changes at each event, and the failure modes that need explicit handling. Edge cases documented before the first line of integration code: what happens when a webhook fires twice, when a subscription renewal fails on the third retry, when a refund is requested for a partially delivered order.
- Weeks 1-4
03Integration build and webhook setup
Gateway SDK integration in your application stack. Payment form or checkout flow built and tested against the gateway's test environment. Webhook endpoint built with signature verification, idempotency keys, and event-ordered processing. Subscription billing logic - plan creation, trial handling, proration, dunning - implemented against the staging environment. Every integration tested against the gateway's test card set before touching a live key.
- Weeks 3-5
04Edge-case testing and reconciliation audit
Test suite covering the cases that break in production: duplicate webhook delivery, payment failure mid-subscription cycle, refund on a subscription that has already renewed, plan change mid-trial, payout to a seller whose account has been flagged. Reconciliation audit: confirm your application's payment records match the gateway's transaction log for every test scenario.
- Final week
05Production cutover and monitoring
Live gateway credentials configured, production environment validated with a real transaction. Monitoring alerts set for payment failures above a threshold, webhook delivery failures, and refund rates. Runbook for the most common payment operations your team will handle post-launch: issuing refunds, pausing subscriptions, updating card details, and investigating disputed charges. Your team handles payment operations independently after handover.
Payment logic that breaks costs you customers. Get it right the first time.
Tell us your billing model - subscriptions, marketplace, one-time, or a mix - and your current tech stack. We'll scope the integration and give you a cost estimate before work starts.
