Senior Integration & Composition Engineer

Client Job Title: Senior Integration & Composition EngineerLocation Denver/Englewood, CO OR West Chester, PA (3 Days Onsite)Duration: 6-12+ Months ContractMandatory Skills JQ, Go Template, REST API, JSONPreferred Skills (Preferred Experience) Python, GO Language, Java, CI/CDMandatory SkillsJQ, Go Template, REST API, JSONPreferred Skills (Preferred Experience)Python, GO Language, Java, CI/CDJob DescriptionSenior Integration & Composition Engineer to design and implement dynamic payload transformations and configuration compositions to integrate multiple systems reliably and efficiently. This role focuses on payload composition, transformation, and system integration across internal systems and external partners. The engineer will use JQ and Go templates to implement dynamic request/response mappings, configuration-driven workflows, and environment-specific integrations while ensuring scalability, resiliency, and compliance.Key ResponsibilitiesDesign and implement integration compositions across APIs, services, and platformsTransform, filter, and enrich JSON payloads using JQBuild reusable and parameterized templates using Go templatingCompose requests/responses for downstream systems based on business rulesSupport system-to-system integration, orchestration, and data mappingTroubleshoot integration issues related to payload structure and transformationsCollaborate with platform, API, and DevOps teams to ensure seamless deploymentsMaintain versioned, reusable templates and transformation logicBuild Go template driven configurations to support reusable, parameterized integrations across environments (DEV, QA, UAT, PROD)Integrate 3rd party platforms with upstream channels and downstream providersImplement standardized error handling and decline mapping to ensure consistent customer and operational experiencesPartner with product, architecture, QA, and operations teams to ensure payment integrations meet business, regulatory, and performance requirementsTroubleshoot production issues related to payment composition logic, payload mismatches, or partner integration failuresContribute to documentation, best practices, and reusable integration assetsRequired Skills & ExperienceHands-on expertise with JQ for JSON filtering, mapping, aggregation, conditionalsStrong proficiency with Go templating, including conditionals, loops, and reusable templates (Helm-style experience is a plus) & payload generationIntegration & APIs - Experience integrating REST-based payment APIs and event-driven flows. REST APIs, JSON, HTTP, API gateways, middleware, or integration platformsExperience in programming and scripting languages such as GO/Java/PythonUnderstanding of payment failure scenarios, declines, and reconciliation impactsExperience supporting high-throughput, low-latency transaction systemsKnowledge in DevOps such as Kubernetes, Helm, CI/CD PipelineFamiliarity with orchestration frameworksStrong debugging and problem-solving skillsPreferred / Nice-to-HavePrior experience with payment platforms and end-to-end payment lifecyclesKnowledge of alternative payment methods, recurring billing, and subscription modelsExposure to cloud-native deployments, CI/CD pipelines, and Kubernetes-based platforms