Ontrac Solutions

You would build inventory management and financial transaction features for a digital auction platform and collaborate with cross-functional teams on scalable solutions. | A bachelor's degree and at least seven years of C# and .NET Core development are required, along with Azure, CI/CD, and modern front-end framework experience. | OVERVIEW OnTrac is seeking a Senior Software Engineer (.NET / C# / Azure) to join a contractor program supporting a large wholesale digital-marketplace customer. The customer is rebuilding its digital auction platform and decoupling it from a legacy auction management system, standing up a new, independent, modern auction backend purpose-built for a digital-first marketplace. Phase 1 delivers the core platform: inventory management, financial transactions, and customer management. The initiative is broad in scope and spans four or more teams. This role is ideal for a hands-on senior engineer who writes production C# on .NET Core, is comfortable on Azure and Azure DevOps, and can collaborate across teams to turn business requirements into maintainable, scalable software. ENGAGEMENT • Expected start: ASAP • Location: United States, fully remote RESPONSIBILITIES • Implement core features for the new platform, which could include inventory management, financial transactions, and customer management • Collaborate closely with team members, other teams, and product managers to translate business requirements into technical solutions • Develop high-quality, maintainable, and efficient C# code within an agile development environment • Design and implement efficient data models and database interactions • Integrate the new system with existing platforms and third-party systems • Conduct code reviews and provide constructive feedback to peers • Troubleshoot and debug issues, ensuring optimal performance and reliability • Contribute to technical documentation and best practices REQUIRED QUALIFICATIONS • Bachelor's degree in Computer Science, Software Engineering, or a related field • 7+ years of experience in C# development, with a strong understanding of object-oriented programming principles • Extensive experience with .NET Core and C# • Familiarity with front-end development using modern frameworks, specifically React • Experience with the Microsoft Azure cloud platform, including core services and infrastructure • Experience creating and optimizing CI/CD pipelines, specifically within Azure DevOps • Understanding of software architecture principles and best practices, with proficiency in applying design patterns to solve technical challenges • Proficiency in designing and developing RESTful APIs • Solid understanding of database systems and storage (e.g., SQL Server, PostgreSQL, NoSQL) and ORM frameworks (e.g., Entity Framework) • Demonstrated ability to write clean, testable, and efficient code • Strong problem-solving skills and attention to detail • Excellent communication and collaboration skills • Experience with agentic workflows • Comfortable working with AI and AI-assisted development tools USEFUL QUALIFICATIONS • Contemporary JavaScript / TypeScript (ES2015+), React Hooks, Next.js, Nx • Experience with a message queue such as Kafka or RabbitMQ • Experience writing GraphQL-interfaced services • Experience working with authentication and authorization

Design and implement Java Spring Boot microservices and own the platform API surface for a government licensing platform. | 8+ years backend Java and Spring Boot experience, Google Cloud Platform production delivery, API design, PostgreSQL, event-driven architecture, and security expertise. | OVERVIEW We are seeking a highly skilled and experienced Senior Software Engineer (Backend / API) to join a contractor program supporting a critical customer engagement: a state government professional licensing and regulatory compliance platform built on Google Cloud. This is greenfield work - infrastructure, data and CI/CD are in place, and the application services are still to be built. This role is ideal for a senior backend engineer with deep Java and Spring Boot experience who owns core domain services end to end and designs the APIs the rest of the platform is built on. The successful candidate will build the licensing, case management, payments, document and notification services and the public and internal API surface, working closely with the client technical lead, the integration engineers, and the mobile and frontend engineers to ensure project success from initial definition through final delivery. Expected start date: 5 October 2026. REQUIRED CREDENTIALS 8+ years of professional backend engineering experience with Java and Spring Boot Production delivery experience on Google Cloud Platform Bachelor's degree in Computer Science or equivalent practical experience REQUIRED QUALIFICATIONS Java 21 and Spring Boot 3.x microservice development API design and ownership: REST, OpenAPI specification, versioning, pagination, error contracts, backward compatibility PostgreSQL, including schema design, indexing, query tuning, and versioned migrations GCP serverless services: Cloud Run, Pub/Sub, Cloud Tasks, Cloud Scheduler Event-driven architecture and messaging patterns (idempotency, retries, dead-letter handling) API security with OAuth 2.0 / OIDC and JWT, including role- and attribute-based authorization Automated testing (JUnit, integration tests) and CI/CD Observability of owned services: structured logging, metrics, tracing, SLOs USEFUL QUALIFICATIONS Experience in government or regulated environments (FIPS, CJIS, HIPAA) - a plus, not a requirement Building APIs consumed by external partners, agencies, or public-facing applications AlloyDB, BigQuery Payment processing integrations and settlement reconciliation GraphQL or gRPC alongside REST Performance and load testing of high-traffic public services Google Cloud Professional certifications SCOPE AND SOLUTION EXPECTATIONS Below covers the scope of work we anticipate the contractor supporting throughout the project timeline. Design and implement Java 21 / Spring Boot microservices on Cloud Run for the core domain: licensing, applications and renewals, case management, payments, documents, and notifications Own the platform API surface - specify it in OpenAPI, keep contracts stable for the mobile, frontend and integration teams, and version changes without breaking consumers Implement PostgreSQL (AlloyDB) persistence, including row-level data isolation, search indexing, and migration strategy Build asynchronous event flows on Pub/Sub and Eventarc, and publish the domain events other services and the integration layer subscribe to Implement scheduled and timer-driven processing with Cloud Tasks and Cloud Scheduler (renewal reminders, expiration sweeps, reconciliation) Implement authentication and authorization across the API surface, including public applicant access and internal staff roles Implement payment flows, including hosted payment page integration and settlement reconciliation Meet platform security and compliance requirements for encryption, auditability, and data isolation Deliver unit and integration test coverage, participate in code reviews, and support CI/CD deployment of owned services Employment Type: CONTRACTOR

Design and implement Java Spring Boot microservices and own the platform API surface for a government licensing platform. | 8+ years backend experience with Java and Spring Boot, Google Cloud production experience, and strong API design skills. | OVERVIEW We are seeking a highly skilled and experienced Senior Software Engineer (Backend / API) to join a contractor program supporting a critical customer engagement: a state government professional licensing and regulatory compliance platform built on Google Cloud. This is greenfield work - infrastructure, data and CI/CD are in place, and the application services are still to be built. This role is ideal for a senior backend engineer with deep Java and Spring Boot experience who owns core domain services end to end and designs the APIs the rest of the platform is built on. The successful candidate will build the licensing, case management, payments, document and notification services and the public and internal API surface, working closely with the client technical lead, the integration engineers, and the mobile and frontend engineers to ensure project success from initial definition through final delivery. Expected start date: 5 October 2026. REQUIRED CREDENTIALS 8+ years of professional backend engineering experience with Java and Spring Boot Production delivery experience on Google Cloud Platform Bachelor's degree in Computer Science or equivalent practical experience REQUIRED QUALIFICATIONS Java 21 and Spring Boot 3.x microservice development API design and ownership: REST, OpenAPI specification, versioning, pagination, error contracts, backward compatibility PostgreSQL, including schema design, indexing, query tuning, and versioned migrations GCP serverless services: Cloud Run, Pub/Sub, Cloud Tasks, Cloud Scheduler Event-driven architecture and messaging patterns (idempotency, retries, dead-letter handling) API security with OAuth 2.0 / OIDC and JWT, including role- and attribute-based authorization Automated testing (JUnit, integration tests) and CI/CD Observability of owned services: structured logging, metrics, tracing, SLOs USEFUL QUALIFICATIONS Experience in government or regulated environments (FIPS, CJIS, HIPAA) - a plus, not a requirement Building APIs consumed by external partners, agencies, or public-facing applications AlloyDB, BigQuery Payment processing integrations and settlement reconciliation GraphQL or gRPC alongside REST Performance and load testing of high-traffic public services Google Cloud Professional certifications SCOPE AND SOLUTION EXPECTATIONS Below covers the scope of work we anticipate the contractor supporting throughout the project timeline. Design and implement Java 21 / Spring Boot microservices on Cloud Run for the core domain: licensing, applications and renewals, case management, payments, documents, and notifications Own the platform API surface - specify it in OpenAPI, keep contracts stable for the mobile, frontend and integration teams, and version changes without breaking consumers Implement PostgreSQL (AlloyDB) persistence, including row-level data isolation, search indexing, and migration strategy Build asynchronous event flows on Pub/Sub and Eventarc, and publish the domain events other services and the integration layer subscribe to Implement scheduled and timer-driven processing with Cloud Tasks and Cloud Scheduler (renewal reminders, expiration sweeps, reconciliation) Implement authentication and authorization across the API surface, including public applicant access and internal staff roles Implement payment flows, including hosted payment page integration and settlement reconciliation Meet platform security and compliance requirements for encryption, auditability, and data isolation Deliver unit and integration test coverage, participate in code reviews, and support CI/CD deployment of owned services Employment Type: CONTRACTOR

Design and implement core domain microservices and own the platform's API surface ensuring stable contracts. | 8+ years backend engineering with Java and Spring Boot, production experience on Google Cloud, bachelor's degree required. | OVERVIEW We are seeking a highly skilled and experienced Senior Software Engineer (Backend / API) to join a contractor program supporting a critical customer engagement: a state government professional licensing and regulatory compliance platform built on Google Cloud. This is greenfield work — infrastructure, data and CI/CD are in place, and the application services are still to be built. This role is ideal for a senior backend engineer with deep Java and Spring Boot experience who owns core domain services end to end and designs the APIs the rest of the platform is built on. The successful candidate will build the licensing, case management, payments, document and notification services and the public and internal API surface, working closely with the client technical lead, the integration engineers, and the mobile and frontend engineers to ensure project success from initial definition through final delivery. Expected start date: 5 October 2026. REQUIRED CREDENTIALS • 8+ years of professional backend engineering experience with Java and Spring Boot • Production delivery experience on Google Cloud Platform • Bachelor's degree in Computer Science or equivalent practical experience REQUIRED QUALIFICATIONS • Java 21 and Spring Boot 3.x microservice development • API design and ownership: REST, OpenAPI specification, versioning, pagination, error contracts, backward compatibility • PostgreSQL, including schema design, indexing, query tuning, and versioned migrations • GCP serverless services: Cloud Run, Pub/Sub, Cloud Tasks, Cloud Scheduler • Event-driven architecture and messaging patterns (idempotency, retries, dead-letter handling) • API security with OAuth 2.0 / OIDC and JWT, including role- and attribute-based authorization • Automated testing (JUnit, integration tests) and CI/CD • Observability of owned services: structured logging, metrics, tracing, SLOs USEFUL QUALIFICATIONS • Experience in government or regulated environments (FIPS, CJIS, HIPAA) — a plus, not a requirement • Building APIs consumed by external partners, agencies, or public-facing applications • AlloyDB, BigQuery • Payment processing integrations and settlement reconciliation • GraphQL or gRPC alongside REST • Performance and load testing of high-traffic public services • Google Cloud Professional certifications SCOPE AND SOLUTION EXPECTATIONS Below covers the scope of work we anticipate the contractor supporting throughout the project timeline. • Design and implement Java 21 / Spring Boot microservices on Cloud Run for the core domain: licensing, applications and renewals, case management, payments, documents, and notifications • Own the platform API surface — specify it in OpenAPI, keep contracts stable for the mobile, frontend and integration teams, and version changes without breaking consumers • Implement PostgreSQL (AlloyDB) persistence, including row-level data isolation, search indexing, and migration strategy • Build asynchronous event flows on Pub/Sub and Eventarc, and publish the domain events other services and the integration layer subscribe to • Implement scheduled and timer-driven processing with Cloud Tasks and Cloud Scheduler (renewal reminders, expiration sweeps, reconciliation) • Implement authentication and authorization across the API surface, including public applicant access and internal staff roles • Implement payment flows, including hosted payment page integration and settlement reconciliation • Meet platform security and compliance requirements for encryption, auditability, and data isolation • Deliver unit and integration test coverage, participate in code reviews, and support CI/CD deployment of owned services