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# Sr. Backend Engineer

- **Company:** Harnham Inc.
- **Location:** Mundelein, IL, United States
- **Experience:** Expert
- **Salary:** $190,000.0 - $210,000.0
- **Contract:** Permanent contract
- **Skills:** Cloud Computing, Relational Databases, Software Engineering, Backend, Integration Frameworks, Api Design, Restful APIs, Web Api
- **Published:** November 8, 2026
- **Apply:** https://www.thejobnetwork.com/job/e7519fd5-9de8-4b99-a1aa-616ea4a014e9/sr-backend-engineer

## About the Role

The position is ideal for an engineer who enjoys building correctness-critical systems, designing scalable APIs, and driving architectural decisions while remaining deeply hands-on with coding. The role offers a clear path toward Staff-level responsibilities through technical impact and ownership., * 6+ years of professional software engineering experience.
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 * Strong backend engineering experience with transactional or correctness-critical systems (booking, reservations, payments, inventory, orders, etc.).
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 * Experience designing and shipping external APIs and third-party integrations.
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 * Strong understanding of relational databases, data modeling, and system design.
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 * Experience building production systems using modern backend technologies and cloud infrastructure.
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## Description

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 * Design, build, and maintain external APIs used by partners and third-party integrations.
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 * Own technical decisions related to API architecture, scalability, performance, and reliability.
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 * Develop systems that support pricing, booking, reservations, inventory management, and transactional workflows.
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 * Create reusable patterns and frameworks that enable other engineers to build integrations efficiently.
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 * Collaborate closely with senior engineering leadership on foundational architecture and long-term technical strategy.
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 * Design and evolve relational data models supporting new products, services, and business capabilities.
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 * Ensure system correctness, observability, and operational excellence across distributed services.
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