Payment Integration · Paris & France

Secure and optimize every transaction

Low acceptance rates, checkout drop-offs, uncertain PCI DSS compliance, poorly managed fraud. Payment is the critical moment in your purchase journey - every friction point translates to lost revenue. We integrate leading PSPs (Adyen, Stripe) to maximize your conversion.

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The challenge

Why rethink your payment integration

Payment is often the neglected part of e-commerce projects - until the numbers speak:

  1. 01 Checkout abandonment rate > 70% - with a significant share linked to payment friction
  2. 02 Sub-optimal acceptance rate: unjustified declines, overly aggressive 3DS, single acquirer
  3. 03 Unclear PCI DSS compliance: card data on your servers, uncontrolled scope, risky audit
  4. 04 Poorly detected fraud: static rules, false positives blocking legitimate customers
  5. 05 Aging PSP integration: v1 API, no reliable webhooks, no retry logic
  6. 06 Checkout not optimized for mobile: classic card form, no Apple Pay / Google Pay
  7. 07 Manual financial reconciliation: discrepancies between PSP and accounting, artisanal reporting
  8. 08 Makeshift multi-currency: merchant-side conversion, no local currency pricing

Solution comparison

PSP: solution comparison

We are Adyen and Stripe experts. Here is our field analysis of leading PSPs:

Adyen (Expert)

Adyen (Expert)

Strengths
  • Acquirer + PSP in a single contract
  • Intelligent multi-acquirer routing
  • Advanced ML risk engine
  • Unified payment terminal (POS)
  • Native Apple Pay, Google Pay
Limitations
  • Opaque pricing (interchange++)
  • Dashboard less intuitive than Stripe
  • Paid premium technical support
Ideal for: Large retailers and international brands with omnichannel payments (web + retail + mobile).

Stripe (Expert)

Strengths
  • Exceptional DX (API, SDK, docs)
  • Pre-built Stripe Elements / Checkout
  • Stripe Connect for marketplaces
  • Billing for subscriptions
  • Radar (ML anti-fraud)
Limitations
  • Not a direct acquirer (relies on partners)
  • Fixed pricing (no interchange negotiation)
  • Less suited for in-store payments
Ideal for: SaaS, marketplaces and pure e-commerce (web/mobile) valuing DX and integration speed.
Checkout.com

Checkout.com

Strengths
  • High-performing European acquirer
  • Modern and well-documented API
  • Competitive interchange++ pricing
  • Extensive local acquisition network
Limitations
  • Less rich ecosystem than Stripe
  • Fewer third-party e-commerce plugins
  • Less responsive support
Ideal for: European e-commerce with high volume looking to optimize acquisition costs.
Mollie

Mollie

Strengths
  • Very fast setup
  • Intuitive interface
  • Native European payment methods (iDEAL, Bancontact)
  • Transparent and competitive pricing
Limitations
  • Fewer enterprise features
  • Basic anti-fraud
  • No multi-acquirer routing
Ideal for: European SMBs with standard needs and a limited budget.
No technology dogma. We recommend the solution best suited to your context, constraints and ambitions. Every choice is documented and justified.

Our methodology

How we deliver

Architects with twenty years behind them, and a delivery process instrumented by AI: scoping, code review, quality and security tooled at every phase. Each step produces concrete deliverables, and we stay through the run.

01
2 to 3 weeks

Payment & checkout audit

Analyze your current payment tunnel: acceptance rate, abandonment rate, fraud, processing costs. Identify friction points and optimization opportunities.
Deliverables
  • Checkout funnel analysis (abandonment rate by step, device, country)
  • Acceptance rate audit by issuer and card type
  • Processing cost analysis (interchange, scheme fees, PSP fees)
  • Fraud risk and current filtering rules assessment
  • PCI DSS compliance audit (scope, SAQ, compensating controls)
  • PSP benchmark (Adyen, Stripe, Checkout.com, Mollie)
  • Recommendation report with quantified business case
02
2 to 3 weeks

Payment architecture & design

Design the target payment architecture: PSP integration, multi-currency management, payment method orchestration, anti-fraud strategy.
Deliverables
  • Target payment architecture (authorization, capture, refund flows)
  • Optimized checkout design (conversion-first, mobile-first)
  • PSP integration specifications (API, webhooks, tokenization)
  • Multi-currency and multi-payment method strategy
  • Anti-fraud rules design (risk scoring, dynamic 3DS)
  • PCI DSS compliance plan (scope reduction via tokenization)
  • Reporting and reconciliation specifications
03
6 to 10 weeks

Integration & PCI DSS certification

Implement the PSP integration, develop the optimized checkout, configure anti-fraud rules, achieve PCI DSS compliance. Load testing and validation with acquirers.
Deliverables
  • PSP integration (Adyen / Stripe) - API, webhooks, tokenization
  • Optimized checkout development (Drop-in or Components)
  • Apple Pay, Google Pay, PayPal, Klarna configuration if applicable
  • Dynamic 3D Secure 2 implementation (SCA exemptions)
  • Anti-fraud rules and risk scoring configuration
  • End-to-end testing by currency, country, payment method
  • PCI DSS compliance - SAQ A or SAQ A-EP based on scope
  • Technical documentation and payment runbook
04
Ongoing

Go-live & continuous optimization

Deploy to production, monitor payment KPIs, continuously optimize acceptance rate and fraud detection.
Deliverables
  • Supervised production launch (war room, enhanced monitoring)
  • Real-time payment KPI monitoring (acceptance rate, fraud, declines)
  • Financial reconciliation dashboards (PSP vs accounting)
  • Continuous anti-fraud rules optimization (monthly review)
  • Checkout A/B testing (payment methods, UX, 3DS flow)
  • Monthly payment performance reporting + updated business case
  • Regulatory watch (PSD2, SCA, PCI DSS v4)

Business value

What you concretely gain

Expected results

Acceptance rate increased by 5 to 15%

Guaranteed PCI DSS compliance

Fraud reduced by 40 to 60%

  1. 01

    Acceptance rate increased by 5 to 15%

    Intelligent routing, retry logic, SCA exemptions, network tokenization - every acceptance rate point gained represents recovered revenue.

  2. 02

    Guaranteed PCI DSS compliance

    PCI scope reduction via tokenization, no card data on your servers. SAQ A or SAQ A-EP validated - legal obligation met, risk eliminated.

  3. 03

    Fraud reduced by 40 to 60%

    ML risk scoring, dynamic 3DS, velocity checks, device fingerprinting - intelligent detection that blocks fraud without blocking legitimate customers.

  4. 04

    Optimized checkout conversion

    One-click checkout (Apple Pay, Google Pay), secure card memorization, mobile-first UX - every friction removed translates to additional conversions.

  5. 05

    Optimized processing costs

    Intelligent routing to the cheapest acquirer, interchange negotiation, scheme fees analysis - 10 to 20% savings on your payment costs.

  6. 06

    Multi-currency and multi-market

    Local payment methods per market (iDEAL, Bancontact, Alipay), local currency pricing, local acquirers - native payment experience on every market.

Client references

They trusted us with this type of engagement

Christian Louboutin

Adyen integration with Apple Pay, Google Pay and multi-currency payments. PCI DSS compliance on Azure cloud infrastructure. Checkout conversion optimization (+12% acceptance rate).

Kering - Boucheron

Multi-market payment architecture (WW & APAC). PSP integration with exotic currency management, local payment methods (Alipay, WeChat Pay) and multi-zone PCI DSS compliance.

Frequently asked questions

Your questions, our answers

01 Adyen or Stripe: how to choose?
Adyen if you have omnichannel payments (web + retail + mobile), significant volumes and advanced multi-market needs. Stripe if you are 100% digital, value DX and need Stripe Connect (marketplace) or Billing (subscriptions). We are experts on both.
02 How to reduce PCI DSS scope?
Via tokenization: card data is collected directly by the PSP (Adyen Drop-in / Stripe Elements) without passing through your servers. Your PCI scope reduces to SAQ A or SAQ A-EP, eliminating 90% of compliance constraints.
03 What is dynamic 3D Secure?
3DS 2.0 allows intelligent application of strong customer authentication (SCA): exemptions for low-risk transactions (< €30, recurring, trusted beneficiary). Result: less friction for legitimate customers, PSD2 compliance respected.
04 How to optimize the acceptance rate?
Several levers: network tokenization (network tokens vs PAN), intelligent retry on soft declines, routing to the cardholder's local acquirer, SCA exemptions, automatic update of expired cards. Each lever can bring 1 to 3 acceptance rate points.
05 How much does a PSP integration cost?
Technical integration takes 6 to 10 weeks depending on complexity (number of payment methods, multi-currency, advanced anti-fraud). Cost depends on scope - a standard checkout is faster than a multi-acquirer architecture with intelligent routing.

Ready to optimize your payment tunnel?

Thirty minutes with an architect - the person who will scope your project, and ship it. We analyze your current checkout and identify conversion levers - no commitment.

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