Senior Full Stack Engineer (Realtime & Voice) Customer Experience Platform

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Full Stack Engineer (Realtime & Voice) Customer Experience Platform based in Canada. This is a senior-level opportunity to build the realtime and voice foundation of an AI-powered customer experience platform serving major travel brands. You will own critical voice capabilities end to end, from telephony integrations and speech pipelines to realtime AI orchestration and performance optimization. The role combines full-stack product development with distributed systems, cloud infrastructure, safety, and enterprise-grade reliability. You will work across React/TypeScript, Scala, Python, and cloud platforms while solving complex low-latency engineering challenges. The team is lean and highly experienced, offering broad ownership and a direct connection between your technical decisions and customer experiences. You will also help shape platform architecture, engineering standards, and the capabilities that enable partners to launch and scale. Own the voice channel end to end, including telephony and CPaaS integrations, streaming speech-to-text and text-to-speech pipelines, realtime AI model orchestration, and latency and quality optimization. Build and enhance product capabilities across the stack using React and TypeScript for front-end experiences, Scala and Python for backend services, and cloud infrastructure on GCP. Design and maintain scalable, multi-tenant architecture that allows multiple enterprise partners to operate from a shared codebase through configuration rather than separate forks. Develop safety and compliance capabilities, including guardrails, content filtering, and integration points for PII redaction. Maintain revenue-critical production systems through strong observability, alerting, incident response, SLA management, and effective rollback strategies. Build platform capabilities that enable forward-deployed engineering teams to configure partner telephony integrations and support successful go-lives. Develop RESTful APIs, microservices, and event-driven systems that support reliable, scalable customer experiences. Collaborate closely with product, design, operations, and other engineering teams to translate complex requirements into pragmatic, iterative solutions. Contribute to architecture and code reviews while mentoring engineers and raising engineering standards across the team. Apply AI coding tools thoughtfully while reviewing, validating, and taking full ownership of all production code. Requirements 6+ years of professional software engineering experience, including senior-level ownership of production systems and strong full-stack capabilities. Hands-on experience with realtime systems such as voice applications, WebRTC/SIP, streaming media, or other low-latency products. Strong front-end development skills with React and TypeScript, combined with backend expertise in Scala or another JVM language and/or Python. Experience with cloud infrastructure on GCP or AWS and with designing, building, and operating production-grade distributed systems. Proven experience developing and maintaining RESTful APIs, microservices, and/or event-driven architectures. Strong understanding of operational excellence, including SLAs, observability, on-call practices, incident response, and rollback planning. Ability to break down complex technical problems, make pragmatic trade-offs, and deliver solutions incrementally. Strong communication and collaboration skills, with the ability to work effectively across product, design, engineering, and operations. Familiarity with AI-assisted development tools and the judgment required to review, improve, and take ownership of AI-generated code. Experience with conversational AI or LLM orchestration is a strong advantage, particularly with technologies such as Deepgram, ElevenLabs, Whisper, or OpenAI Realtime. Experience with cloud telephony or