Payment Processing Gateway
PCI-DSS compliant payment gateway processing $50M+ monthly transactions with 99.995% uptime and fraud prevention.
Key Results
Client
Series A Payments Company
Industry
Financial Technology
Location
London, UK
Overview
A Series A payments company needed a custom payment gateway to reduce their dependency on third-party processors and lower transaction fees. Their existing setup involved multiple payment providers with inconsistent APIs, high failure rates, and limited support for emerging markets.
We designed and built a PCI-DSS Level 1 compliant payment processing gateway in Rust, supporting 15+ payment methods across 30 countries. The system intelligently routes transactions to minimize fees and maximize success rates through smart retry logic and fallback providers.
The Challenge
PCI-DSS Level 1 Compliance
Build a system that meets the most stringent PCI-DSS compliance requirements, including secure cardholder data handling, network segmentation, and continuous monitoring.
Multi-Currency & Multi-Region
Support 15+ payment methods and 25+ currencies across 30 countries with region-specific regulatory requirements and settlement processes.
High Availability
Ensure 99.99% uptime for payment processing — every minute of downtime directly translates to lost revenue for merchants.
Intelligent Routing
Maximize transaction success rates by dynamically routing payments across multiple acquirers based on cost, success probability, and settlement speed.
Our Solution
Architecture Overview
Gateway Layer
Rust + PCI-DSS Vault
Routing Engine
Smart Router + Fallback Logic
Ledger Layer
PostgreSQL + Event Sourcing
PCI-Compliant Card Vault
Built an isolated, hardened card vault in Rust with HSM-backed encryption. Tokenization ensures sensitive card data never leaves the vault, while merchants work with secure tokens.
Intelligent Payment Routing
Developed a smart routing engine that selects the optimal payment processor based on transaction type, currency, merchant category, historical success rates, and cost optimization.
Event-Sourced Ledger
Implemented a double-entry accounting ledger using event sourcing in PostgreSQL. Every financial state change is recorded as an immutable event, enabling complete auditability and reconciliation.
Automated Reconciliation
Built an automated reconciliation engine that matches transactions across acquirers, banks, and internal records. Discrepancies are flagged and categorized for efficient resolution.
Performance Metrics
Transaction Throughput
Response Time Distribution
$50M+
Monthly Volume
Level 1
PCI-DSS
99.7%
Success Rate
<200ms
Processing Time
Technology Stack
Backend & Processing
- Rust 1.74
- Actix Web
- Stripe / Adyen SDKs
Data & Ledger
- PostgreSQL 15
- Redis
- Event Store
Infrastructure
- AWS (PCI scope)
- Vault (HSM)
- PagerDuty
Outcomes & Impact
Financial Impact
- Reduced average transaction fees by 22% through intelligent routing
- Increased transaction success rate from 96.1% to 99.7%
- Recovered $1.8M annually from smart retry on soft declines
Technical Achievements
- PCI-DSS Level 1 certification achieved on first audit
- Sub-200ms end-to-end processing time for 95th percentile
- 99.99% uptime maintained over 18 months of operation
Merchant Experience
- Unified API for 15+ payment methods reduced integration time from weeks to days
- Real-time webhooks and comprehensive dashboard for transaction monitoring
- Self-service onboarding reduced merchant setup from 2 weeks to 2 hours
Compliance & Risk
- Automated PCI-DSS compliance reporting reduced audit preparation by 80%
- Real-time fraud scoring reduced chargebacks by 35%
- Complete transaction audit trail meets regulatory requirements in 30 countries
“Our payment success rates jumped from 96% to 99.7% within weeks of launch. The intelligent routing alone saves us over $500K per year. BeluMind’ expertise in building secure, high-performance financial systems is unmatched.”
James O’Brien
CEO, PayStream
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