Senior Software Engineer

We're building the infrastructure that knows every customer before they call. We meet customers where they are, in their language and wherever they live, while navigating complex regulatory environments. Our Voice AI handles thousands of live calls every day for Fortune 500 banks and insurers, end to end. Call volume is 3x-ing monthly. We're hitting problems most startups never see: real-time voice AI at scale, legacy banking infrastructure, enterprise telephony, regulatory constraints.Role Description: The Senior Software Engineer role at Domu is a full-time, on-site position based in San Francisco, CA. This role is responsible for designing, implementing, and maintaining core backend services that power Domu’s AI-driven engagement platform. Day-to-day tasks include architecting scalable systems, writing high-quality code, and collaborating with product and data teams to deliver new features and integrations. The Senior Software Engineer will optimize system performance, ensure security and compliance, and contribute to technical decision-making and roadmap planning. This role also involves improving development practices, and helping shape the engineering culture as the product and team grow.QualificationsStrong foundation in Computer Science, including data structures, algorithms, and system design.Proficiency in Back-End Web Development and Software Development, building scalable, secure services and APIs.Hands-on experience with Programming and Object-Oriented Programming (OOP) in one or more modern languages (e.g., Java, Python, Go, C#, or similar).Experience with cloud platforms (e.g., AWS, GCP, or Azure), containers, and microservices architectures.Knowledge of databases, messaging systems, and distributed systems concepts.Ability to write clean, testable code and familiarity with CI/CD, version control, and automated testing.Effective communication and collaboration skills, with experience working in cross-functional teams.Experience in fintech, insurance technology, or regulated environments, and familiarity with AI-driven products, is a plus.Extras we're Excited AboutTelephony/Voice infrastructure - SIP, SRTP, WebRTC, or platforms like Telnyx, Twilio, LiveKitHigh-throughput distributed systems - queue workers, event-driven architectures, handling 1M+ daily transactionsPostgreSQL at scale - query optimization, replication, connection poolingKubernetes - production deployments, scaling stateful servicesReal-time data pipelines - ClickHouse, Kafka, or similar OLAP/streaming solutionsAWS infrastructure - SQS, containerized deploymentsCompliance-conscious environments - SOC 2, ISO 27001, or fintech/enterprise security requirementsExperience with AI/ML integrations in production (LLMs, voice AI)Familiarity with contact center / dialer systemsYou've been through the early stages of a startup before.You care about the craft. You want to build something good, not just something that works.Ideal Archetypes:Head of Eng / Tech Lead at a Series A/B startup (5–20 engineers), built and scaled core infra from scratchSenior Engineer who was one of the first 10 hires and is ready for that feeling againFounding Engineer through Series B/C, owns systems end-to-end, wants a new zero-to-one challengeStaff Engineer at a Series C/D slowed by process, wants to move fast againRepeat startup engineer, 2–3 stints, specifically seeks small teams with hard problemsWhat we offerHealthcareweekly stipend for food and transportationgym membershipequipment budget (strict rules on noisy mechanical keyboards)whatever tools you need