Back to work
High-Throughput Financial Systems

Payment Orchestration Platform

Client

Meridian Financial

Industry

Fintech / Lending

Duration

5 Months

Services

Product Engineering, Cloud & DevOps, Data Engineering

The Challenge

Solving Double-Entry Write Concurrency and API Lag

Meridian Financial experienced significant latency spikes and occasional reconciliation discrepancies in their payment database. Multiple microservices attempted to query and debit ledger balances simultaneously, leading to database lock contention, slow API responses (averaging 1.2s), and extensive manual validation effort required by finance administrators every morning to locate discrepancies.

Our Approach

Double-Entry Ledger Architecture & Caching

We designed a decoupled system architecture. First, we implemented an immutable double-entry ledger ledger database model with transaction safety checks (optimistic locking) to ensure balances cannot slide. Second, we built a Redis-backed queue system that processes transaction actions asynchronously, responding to API callers immediately. Third, we established secure SFTP and API integrations directly with banking networks for real-time reconciliation logs.

Topology

System Architecture

We design clean system flows that separate concern layers. Check out how data moves securely through this operational framework.

Treasury Flow Architecture
Client API
QueueRedis Broker
Worker Pods
PostgreSQL Immutable Ledger (Journal Model)
Technical Depth

Complex Challenges Solved

Database Lock Contention under Concurrency

We removed raw SQL transaction locks by designing a credit/debit journal model, transforming updates into rapid inserts and caching running balances in Redis.

API Timeout Errors during Peak Hours

We refactored the checkout flow to respond with a correlation ID instantly, processing the actual credit validation asynchronously in a worker pod.

Metrics

Measurable Results

We stay accountable for database performance and business outcomes.

42% faster transaction processing speed (under 180ms average)
99.99% system uptime achieved across all payout API endpoints
100% automated reconciliation, eliminating 2 hours of daily manual reports
Zero ledger balance slide incidents reported in production
They replaced a complex, legacy two-year roadmap with a high-availability working platform in five months. The database and cloud architecture still hasn't needed a rewrite.
Elena VasquezCTO, Meridian Financial
Stack

Technologies Utilised

Next.jsNode.jsPostgreSQLRedisAWS RDSTerraformDockerSnyk
Maintenance

What Happened Next

We provide ongoing SLA monitoring, server patches, scaling adjustments, and security IAM audits under a monthly operability agreement.

Have a similar system to engineer?

Discuss your system constraints, data structures, and compliance rules with a senior software architect.