Senior Backend Engineer

Senior Backend Engineer Branding Brand is hiring a Senior Backend Engineer for a 12-week contract engagement (June 2026 to August 2026) to design and ship a new backend service to production for one of our clients. You will own delivery end-to-end of a reactive Java service built on Spring WebFlux, deployed on Kubernetes, with Redis for caching and Databricks as the long-term data store. The workload is bursty and high throughput, so the role requires solid instincts for idempotency, at-least-once delivery, and scaling under burst load. This is a fully remote contract position. The candidate must be located in the United States and able to work as an independent contractor. No C2C. Key Responsibilities: Design and build: Own the design and end-to-end implementation of a new backend service in Java 21 and Spring WebFlux Build reactive, nonblocking HTTP endpoints that are racesafe and idempotent under retry Make architecture decisions on caching, write paths, error handling, and scaling, and document the tradeoffs Scale and operate: Design the Redis caching layer for hot reads, idempotency de-dupe, and readthrough patterns Design the async write path from the service to Databricks (queue or stream, batch writer, retry semantics) Configure Kubernetes deployments, horizontal pod autoscaling, and graceful shutdown for safe deploys Author K6 load tests for both steadystate and bursty traffic patterns Wire up structured logging, metrics, and alerting for production critical paths Su