Java Software Engineer

Latam Based

USD Payment

Contractor role- US Client

Full-time

Senior Software Engineer (Backend) — Java/Spring, Kafka, AWS

(Payments • Microservices • PostgreSQL + MySQL)

About the product

We operate a high-throughput platform that recovers declined transactions across multiple payment gateways. The system is a microservice architecture (e.g., Auth, Billing Engine, Recovery Orchestrator, Risk/Scoring) communicating via API and Kafka. Our primary OLTP stores are PostgreSQL, and some services use MySQL. Operational/search analytics flow to Elasticsearch via connectors—everything runs on AWS.

What you’ll do

• Design and own Spring Boot microservices that power the decline-recovery lifecycle (scoring, retry scheduling, gateway orchestration, audit/reconciliation).

• Build event-driven workflows (Kafka producers/consumers, idempotency, ordering/partitioning, DLQs, replays/backfills, Avro/Protobuf schema evolution).

• Model and tune PostgreSQL and MySQL schemas (query plans, indexing, locking/isolation, migrations, connection pooling) and manage read replicas/partitioning where appropriate.

• Evolve ingestion to Elasticsearch (mappings, analyzers, ILM, rollovers, reindexing) via Kafka Connect or similar.

• Ship reliable code with contract/integration tests, load tests, and clear SLIs/SLOs.

• Partner with product/data/risk to run experiments (feature flags, A/B) that increase approval-rate uplift, reduce latency, and grow recovered revenue.

What you’ll bring

• 6+ years building backend systems; 4+ years with Java 17+/Spring Boot in production.

• Deep Kafka expertise (consumer groups, lag/throughput tuning, retries/backoff, DLQs, replay strategies).

• Strong PostgreSQL and MySQL experience (InnoDB, Aurora/RDS, HikariCP, isolation levels, deadlock avoidance, schema design, migrations).

• Hands-on Elasticsearch (mappings, performance, ILM).

• Solid AWS background (VPC, ECS/EKS/Fargate, MSK, IAM, KMS/Secrets Manager, ALB/CloudWatch).

• Security/compliance mindset (PII handling, least privilege, auditability; PCI-aware practices).

• Excellent ownership, communication, and mentorship.

Nice to have

• Payments/fintech background (gateway integrations, dunning/retry strategies, risk signals).

Our stack

• Java 17+, Spring Boot 3+, Kafka/MSK, Schema Registry (Avro/Protobuf), PostgreSQL + MySQL (Aurora/ RDS), Elasticsearch, Redis, Docker, GitHub Actions, Grafana.

How we work

• Small, senior-leaning teams; pragmatic reviews; trunk-based or short-lived branches.

• You build it, you run it; blameless post-mortems; data-driven decisions.