Senior Backend Developer (Java / Spring / AWS)

Role & responsibilities

Core Java & Frameworks
• Java 17+ (we run the latest LTS) records, sealed types, streams and modern language features.
• Spring Boot in depth, including WebFlux and Spring Security (OAuth2 Resource Server).
• Project Reactor `Mono`/`Flux` composition, error operators, backpressure and retries; no `.block()`, `Thread.sleep()` or blocking SDKs.
• Gradle multi-module builds, Lombok, Jackson.
Data
• PostgreSQL at a professional level — schema design, indexing and query plans.
• R2DBC or equivalent reactive data access, and jOOQ or comparable type-safe SQL tooling.
• Flyway or Liquibase migrations validated in CI.
Cloud & Messaging
• Hands-on AWS — Lambda, SQS (FIFO semantics, visibility timeouts, DLQs), EventBridge, S3, Secrets Manager, ECS Fargate, RDS/Aurora, CloudWatch, IAM.
• AWS SDK v2 async clients or Spring Cloud AWS.
• Infrastructure as Code — CloudFormation, or SAM/CDK/Terraform with willingness to work in CloudFormation.
APIs & Contracts
• OpenAPI 3, REST conventions, versioning, consistent error contracts and bean validation.
Quality & Delivery
• JUnit 5, Mockito, Spring Boot Test, Reactor Test — meaningful tests for both success and failure paths.
• Docker and Compose for local development.
• Git, pull-request workflow and GitHub Actions or equivalent CI/CD.
• SonarQube or similar static analysis, with coverage discipline.
Engineering Judgment
• Distributed-systems fluency — idempotency, at-least-once delivery, retries, timeouts, partial failure and eventual consistency.
• Strong analytical, debugging and communication skills; owns delivery end-to-end.

Preferred candidate profile

• OpenTelemetry / distributed tracing; Grafana, Tempo, Prometheus or Loki.
• Snowflake or another cloud data warehouse; large-scale ingestion pipelines.
• Spring Cloud Function on Lambda, and JVM cold-start tuning (CRaC, SnapStart, fat JARs).
• LocalStack for local AWS emulation.
• Serverless cost/performance tuning and JVM tuning for containers.
• Enterprise SSO (Azure Entra, OAuth2 introspection) and centralized entitlement/RBAC services.
• OWASP Top 10 awareness and secure code review.
• Agile/Scrum delivery and trunk-friendly branching.