Career OS

Portfolio Project

Enterprise Payment Management Platform

A production-style Java/Spring Boot backend — the headline of your portfolio.

Evolved from the Recon reconciliation engine. · Stack: Java 21 · Spring Boot 3 · PostgreSQL · Redis · Docker · GitHub Actions · AWS

0 / 17 features shipped
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🧠 Explain it in one minute

What it is: A backend API for an enterprise payment platform. Organisations onboard, invite users with roles, and submit payment requests that flow through an approval workflow. Every state change is written to an immutable audit trail. Money is stored as long (paise) — never floating point.

Why it exists (the problem): In real payment/enterprise systems, you can't let anyone move money. You need who can do what (roles/permissions), a paper trail (audit), correctness under retries (idempotency + transactions), and proof it works (tests). This project is that problem, built from scratch.

How a request flows: Controller → validation (DTO) → Service (business rules + @Transactional) → Repository (JPA) → PostgreSQL. Auth is a JWT filter in front. Hot reads are cached in Redis. It's containerised with Docker Compose and deployed on AWS.

Your interview line: “I have professional exposure to banking/payment systems and testing, and I transitioned into backend engineering by designing and building a production-style Java/Spring Boot payment platform end to end.”

Milestones

Each feature solves a real problem and maps to a concept you're learning. Tick a feature when it's shipped & tested.

M1 Foundation Week 1
Project skeleton Professional repo structure
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User + Organization CRUD REST + persistence
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M2 Security & Access Week 6
Authentication + JWT Security fundamentals
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Roles + permissions Authorization
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Audit Trail Real enterprise requirement
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M3 API Quality Week 7
Validation + global errors API quality
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Pagination + filtering Real API patterns
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Notifications Async thinking
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M4 Testing & Observability Week 9
JUnit + Mockito tests Quality
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Logging + observability Debugging
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M5 Performance & Packaging Week 10
Redis cache Performance
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Docker Compose Deployment skill
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M6 Ship It Week 12
CI/CD Engineering workflow
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AWS deployment Cloud exposure
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M7 Prove It Week 14
Load/performance test Engineering mindset
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Architecture + design doc Interview readiness
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M8 Release Week 16
v1.0 release Portfolio proof
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