Available for remote roles globally

Usman Ejaz

Backend Engineer · Java · Spring Boot · Fintech · PCI-Compliant Systems at Scale · 99.99% Uptime · Sub-100ms APIs

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0
Live APIs
0
Enterprise Clients
99.99%
Uptime SLA
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// About

Building the backbone of fintech

I'm a backend engineer specialising in high-throughput payment infrastructure. At i2c Inc., I build and maintain systems that process millions of card transactions daily across 200+ global enterprise clients — all within PCI-DSS compliance requirements.

My toolkit is Java EE & Spring Boot on microservices, hardened with security-first thinking. I've also built automation pipelines, ML-backed APIs, and full-stack products with Python and React.

CGPA 3.7 from PUCIT. 2+ years in enterprise fintech. Open to remote roles worldwide.

< 100ms
API response time for 216 live endpoints in production
30+
Countries served by applications I maintain daily
20 svcs
Build pipeline modernised from Ant → Maven, ~30% faster builds
JDK 21
Led end-to-end Java 8 → JDK 21 migration across 5 production apps
// Work History

Where I've built things

JUN 2024 – PRESENT
Software Engineer
i2c Inc. — Global Payment Processing & Fintech Infrastructure
  • Architected 20+ RESTful microservices using Spring Boot & Apache Struts serving 216 live API endpoints at sub-100ms latency under high concurrency.
  • Maintained 5 enterprise-grade fintech applications for 200+ clients across 30+ countries with a 99.99% uptime SLA.
  • Engineered fault-tolerant batch scheduling services in Java EE processing high-volume transaction reconciliation with zero data loss.
  • Developed PCI-DSS–compliant security modules including Content Security Policies that passed all compliance audits.
  • Led JDK migration Java 8 → JDK 21 across 5 production apps, eliminating deprecated APIs.
  • Modernised build pipeline for 20 services from Ant → Maven, cutting build time ~30%.
  • Migrated web layer from Apache Struts 1.0 → Struts 7, closing critical CVEs.
Java EESpring BootMicroservicesREST APIsPCI-DSSInformix SQLDockerTeamCityAWS S3
OCT 2023 – JUN 2024
Associate Software Engineer
Optimus Fox @ DataRovers — Multi-domain Client Solutions
  • Built Power BI dashboards with DAX measures, reducing client reporting time by ~40%.
  • Deployed and monitored ML models on Azure ML, automating retraining to maintain >90% prediction accuracy.
  • Designed CI/CD pipelines via GitHub Actions, enabling weekly release cadence.
  • Migrated 3 legacy apps to React, improving load times and UX.
PythonPower BIAzure MLReact.jsGitHub ActionsCI/CD
// Technical Arsenal

Tools of the trade

☕
Core Languages
Java EEPython 3SQLBashJavaScript
🏗️
Backend Frameworks
Spring BootSpring SecuritySpring BatchApache StrutsFlaskDRF
🔗
API & Architecture
MicroservicesREST APIsAPI GatewayBatch SchedulersSDK Development
☁️
Cloud & DevOps
AWS S3AWS EC2Azure MLDockerTeamCityGitHub ActionsMaven
🗄️
Databases
PostgreSQLMySQLInformix SQLMongoDBRedisSupabase
🔐
Security & Compliance
PCI-DSSOWASPJWT / OAuth2CSPSecure Code Review
// Selected Work

Things I've shipped

01 / Production
S3 + RESTful API Gateway
216 live REST APIs powering card processing for 200+ global enterprise fintech clients at sub-100ms latency with 99.99% uptime SLA.
216
Live APIs
<100ms
Response
Java EESpring BootAWS S3Informix SQL
02 / FYP
Human Activity Recognition
Multi-modal IoT pipeline ingesting sensor data from Android, smart glasses & watches via WebSockets. TensorFlow ML models for real-time activity classification with live health predictions.
3
Device Types
Real-time
ML Inference
React.jsDRFTensorFlowPostgreSQLAndroid
03 / Product
SubsTrackr
Full-stack subscription management app — add, cancel & manage recurring services with smart push notifications for payment alerts and analytics dashboards with cost breakdowns.
OAuth2
Auth
Multi-device
Sync
FlaskSupabasePostgreSQLFlutter
// Open to opportunities

Let's build
something great

Available for remote full-time & contract roles globally. Fintech backends, API platforms, automation consulting — let's talk.

✉ ejazusman99@gmail.com LinkedIn GitHub Stack Overflow