Senior Backend Engineer

Senior Backend EngineerBranding 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 WebFluxBuild reactive, nonblocking endpoints that are racesafe and idempotent under retryMake architecture decisions on caching, write paths, error handling, and scaling, and document the tradeoffsScale and operate:Design the Redis caching layer for hot reads, idempotency de-dupe, and readthrough patternsDesign 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 deploysAuthor K6 load tests for both steadystate and bursty traffic patternsWire up structured logging, metrics, and alerting for production critical pathsSupport & maintain:Troubleshoot issues across the API, caching, and datawrite layers in development and productionParticipate in design reviews, code reviews, and Agile ceremoniesProvide production support through the contract period, including issue triage and resolutionTech Stack:Language and framework: Java 21, Spring WebFlux, Project ReactorAPI Gateway: ApigeeCaching: RedisData store: Databricks (longterm, analytical), accessed via async batched writesMessaging and async: SQS, Kafka, or KinesisContainer platform: KubernetesPerformance testing: K6Cloud: AWS or AzureRequired Skills and Qualifications:6+ years of backend development experienceHands-on experience with reactive programming and Project Reactor (Mono, Flux, non-blocking IO)Production experience with Java and Spring WebFlux building RESTful or reactive microservicesExperience designing for idempotency, retries, and at least once delivery semanticsComfort designing and operating services under bursty, high throughput workloadsExperience operating production services in a major public cloud such as Azure or AWSFamiliarity with data warehouse or lakehouse platforms (Databricks, Snowflake, BigQuery) as integration targets from an application serviceExperience load testing services with K6, Gatling, Locust, JMeter, or equivalentCommitment to secure coding practices and ongoing security awarenessStrong problem solving and communication skillsQualifications:Education:Bachelor's degree in computer science, Information Systems, Business, or related fieldAbout Us:Branding Brand launched in 2008 as an interactive marketing firm and quickly evolved into the largest and fastest growing provider of mobile commerce apps and sites for retailers.Branding Brand is a supporter of the Whitehouse Equal Pay Pledge, and a Top Workplaces award winner.Branding Brand is also an equal opportunity employer. We seek applicants of diverse backgrounds and hire without regard to race, color, gender, religion, national origin, ancestry, citizenship, individuals with disabilities, age, sexual orientation, protected veterans, or any other characteristic protected by law.The hourly rate for this position is $25/hr-$70/hr.