Principal Research & Engineering - Realtime Voice AI

About the Role

Voice is becoming the highest-stakes interface for AI, where quality depends on speed, naturalness, interruption handling, emotional nuance, and reliability in real-world conditions. We are looking for a hands-on technical leader to define and build Inflection’s realtime Voice AI stack across speech models, streaming systems, voice-agent runtime, and evaluation. This person will help shape how emotionally intelligent AI shows up in spoken interactions, partnering across research, engineering, product, and design to deliver voice agents that feel responsive, trustworthy, and useful in enterprise settings.

What You’ll Do

• Establish the technical roadmap for Inflection's realtime Voice AI stack, encompassing streaming ASR, TTS, speech-to-speech, speech LLMs, turn-taking, barge-in, latency, and reliability.
• Utilize a 1,000 GPU cluster to support performance benchmarking and extensive experimentation.
• Determine build-vs-buy-vs-train strategies for core audio, speech, and realtime interaction components.
• Direct research and engineering efforts focused on speech quality, naturalness, expressiveness, emotional fit, controllability, and production readiness.
• Collaborate with infrastructure, product, design, and agentic AI teams to deploy voice agents for enterprise workflows.
• Develop evaluation systems measuring voice quality through metrics such as clarity, emotional appropriateness, interruption handling, task success, user preference, latency, and reliability, moving beyond standard WER.
• Refine production voice behavior by debugging across runtime, model, evaluation, data, and product layers.
• Mentor, and Coach a team specializing in speech research, audio infrastructure, realtime systems, and evaluation.

What We’re Looking For

• Experience leading or serving as a principal Research and Engineering contributor to realtime voice, speech, audio AI, or conversational AI systems in production.
• Experience with one or more of: streaming ASR, TTS, speech-to-speech systems, speech LLMs, audio tokenization, multimodal models, barge-in, low-latency inference, or realtime agents.
• Strong technical judgment across both speech modeling and production systems.
• Ability to define voice quality in terms of user and customer outcomes, not only offline model metrics.
• Experience designing or using evaluation systems that capture real user experience.
• Strong product intuition for natural, trustworthy, emotionally appropriate voice interactions.
• Ability to lead senior technical talent while staying close to the code, architecture, and debugging work.
• Have a bachelor’s degree or equivalent in a related field to the offered position requirements

Employee Pay Disclosures

At Inflection AI, we aim to attract and retain the best employees and compensate them in a way that appropriately and fairly values their individual contributions to the company. For this role, Inflection AI estimates a starting annual base salary to fall within the range of $400,000 to $550,000, depending on a candidate’s qualifications and level of experience. This role also includes a meaningful equity component, allowing employees to share in the long-term success of the company.

Benefits

Inflection AI values and supports our team’s mental, emotional, financial and physical health. We are focused on building a positive, safe, inclusive and inspiring place to work. Our benefits include: 

• Robust medical, dental and vision options with employer contributions for HSA, FSA and DFSA
• 401k matching program 
• Flexible Time Off, 10 paid holidays, 5 days sick leave
• Parental, Medical and Family care leave 
• Generous cell-phone, wellness and office set up stipends 
• Support of country-specific visa needs for international employees living in the Bay Area