Senior Java Application Architect

CloudSmiths; Johannesburg; On-site; ZAR 300 000 - 400 000; Part time

Job summary

A leading technology firm seeks a Senior Java Application Architect to drive the architecture and development of a payment gateway on Google Cloud. This role involves ensuring compliance with security standards and implementing low-latency transaction processing. The ideal candidate has 8-10 years of experience in Java engineering and a strong background in fintech applications. The firm offers a contract role based in Johannesburg, providing a dynamic environment for professional growth and impact across Africa and beyond.

Qualifications

• 8-10 years in Java engineering, 3-5 years as an Application Architect in payments or fintech.
• Experience with payment gateway systems.
• Proven production experience on GCP.

Responsibilities

• Lead the planning and architecture design of a payment gateway.
• Deliver production integrations with external services.
• Design scalable microservices for multi-region expansion.

Skills

Java

Spring Boot

GCP

API Development

OAuth2

Education

Bachelor's degree in Computer Science or related field

Tools

Junit

Terraform

Cloud SQL

Job description

We are looking for a hands‑on Senior Java Application Architect to lead the planning architecture design and development of a payment gateway. This is a high‑impact role where you will build a solution on Google Cloud (GCP) designated for rollout across Africa and international markets!

You will own the end‑to‑end architecture with a strong emphasis on security compliance (PCI POPIA / GDPR) and operational observability. This is not just a diagramming role; you will lead the Java implementation while ensuring the platform delivers low‑latency high‑throughput transaction processing.

Key Outcomes You Will Drive

• Architect a PCI‑aligned low‑latency payment gateway on GCP with clear SLIs / SLOs
• Deliver production integrations with external providers including mobile‑money services (e.g. Tigo Pesa M‑Pesa Airtel Money) and MNO / banking APIs.
• Design scalable microservices ready for multi‑region expansion (ZA / EU / UK) with robust reconciliation idempotency and retries
• Embed PCI DSS controls tokenization and key management while preparing for PSD2 / UK requirement

The Tech Stack

• Java 17 Spring Boot / Spring Cloud JPA / Hibernate (Reactive / WebFlux is a plus)
• OAuth2 / OIDC mTLS HMAC API policy enforcement
• Cloud Run (Primary Runtime) and / or GKE Autopilot
• Cloud SQL (MySQL / Postgres) AlloyDB Memorystore (Redis) BigQuery
• Pub / Sub Dataflow

CI / CD (Cloud Build / GitHub Actions) Terraform (IaC)

Who We Are Looking For

• 810 years in Java engineering with 35 years as an Application / Domain Architect in payments or fintech.
• You have built or significantly evolved a payment gateway acquiring platform or wallet / PSP system.
• Experience with wallet / mobile money flows (e.g. M‑Pesa Tigo Pesa) regarding KYC float and settlement is strongly preferred.
• Proven production experience on GCP.
• Deep understanding of high‑availability traffic shaping circuit breakers saga / outbox patterns and event‑driven systems.

Required Experience

Senior IC

Key Skills

Junit,General Ledger Accounting,End User Support,JQuery,Blackberry

Employment Details

Employment Type: Contract

Experience: years

Vacancy: 1