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# Founding Senior Software Engineer (Backend)

- **Company:** Retell Ai
- **Location:** Redwood City, CA, United States (Remote available)
- **Experience:** Expert
- **Salary:** $215,000.0 - $290,000.0
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), Artificial Intelligence, System Configuration, Data Structures, Software Debugging, DevOps, Programming Tools, Web Application Frameworks, Express.js, Backend, Prompt Orchestration
- **Published:** November 7, 2026
- **Apply:** https://www.juju.com/job/28_25304_aa3451407bec86e289df76cd3ae45f78

## About the Role

* Have 2+ years of backend development experience with a degree in CS, CE, or EE.
 * Take ownership like a founder, with a passion for impactful software.
 * Thrive in fast-paced, ambiguous environments, solving new problems with curiosity.
 * Communicate clearly, collaborate across teams, and drive momentum.
 * Have startup experience or grit to adapt, with bonus points for cloud infra/DevOps knowledge., * Online Assessment (25-30 min): One HackerRank coding questions on practical problem-solving (7 days to complete).
 * Technical Phone Interview 1 (30 min): Live coding on CoderPad, focusing on data structures and algorithms.
 * Technical Phone Interview 2 (30-45 min): Deeper CoderPad session on algorithmic thinking and coding fluency.
 * Onsite/Virtual Interviews (2-3 hrs): Hosted in our office if located in the Bay Area or virtual, with three rounds:
 * Practical Coding: Tackle real-world coding tasks with debugging in a basic environment set up like Python Flask or Node.js Express, etc.
 * System Design: Architect a production-ready system.
 * Tools & Automation: Build automations or improve workflows in any basic environment setup like Python Flask or Node.js Express, etc.

## Description

As a Founding 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., * 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.