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IT Consulting and Services

Sr Software engineer/Backend

California, United StatesOnsiteFull TimeSeniorPosted 2 months agoVisa sponsorship available

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Role summary

As a Senior Backend Engineer, you will be instrumental in building the core systems that power millions of AI-driven conversations. This role involves tackling real-time audio, global telephony, and developer tooling, working across the full stack with the founding team. You will design and build scalable backend systems, DevOps workflows, and foundational architecture for prompt orchestration, testing frameworks, and telephony integrations. The position offers rapid feedback loops, customer collaboration, and the opportunity to define a category-leading product in a fast-paced, high-impact environment.

ABOUT THE ROLE

As a Senior Backend Engineer, you’ll shape the core systems powering millions of AI-driven conversations. You’ll tackle real-time audio, global telephony, and developer tooling, working across the stack with the founding team. This high-impact role offers rapid feedback loops, customer collaboration, and the chance to define a category-leading product.

KEY RESPONSIBILITIES

Build foundational architecture for Retell's platform, such as prompt orchestration, testing frameworks, observability dashboards, and telephony integrations.

Design scalable backend systems and DevOps workflows for reliable performance across millions of calls.

Lead complex projects from architecture to production, driving delivery and monitoring.

Collaborate with product and design teams to create intuitive APIs and interfaces for quick customer onboarding.

Support customer onboarding, troubleshoot issues, and turn feedback into product improvements.

YOU MIGHT THRIVE IF

Have 8 years of backend development experience and a strong foundation in CS fundamentals (CS/CE/EE degree or equivalent).

Have worked on scalable, high-performance backend systems — especially anything involving concurrency, data, storage, or distributed components.

Take ownership like a founder and enjoy building core systems that need to be fast, reliable, and correct.

Thrive in fast-moving, ambiguous environments where you learn quickly and solve new technical problems.

Communicate clearly, collaborate well across teams, and move work forward with momentum.

Have startup experience or the grit to operate in a high-velocity environment — bonus points if you’ve worked on infrastructure, databases, or large-scale backend systems.

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