Lead Voice AI Engineer at Cresta - $270K + Equity

Cresta; Newark (NJ); On-site; USD 205,000 - 270,000; Full time

Benefits offered by this job

Medical coverage

Flexible PTO

Remote work stipend

Parental leave

Retirement savings

Wellness allowance

Meal benefits

Job summary

Cresta is seeking a Lead Engineer, AI Agent Voice Experience to build the next generation of AI-powered voice systems for the contact center. You will work at the intersection of speech, language, and real-time production systems, improving how AI listens, understands, reasons, empathizes, and responds in live customer conversations.

You will develop and deploy end-to-end ML systems for ASR, TTS, and agentic workflows, collaborating with researchers, product, and platform teams to deliver

Qualifications

• 5+ years of experience building, evaluating, and deploying machine learning systems in production.
• Demonstrated experience leading fast-moving, highly technical teams.
• Strong communication skills and cross-functional influence.

Responsibilities

• Design, train, evaluate, and deploy machine learning systems powering real-time voice experiences (speech-to-text, turn detection, text-to-speech, speech-to-speech) and insights generation.
• Improve quality through error analysis, data curation, metrics, benchmarking, and iterative model improvement.
• Build evaluation frameworks for complex voice and agentic systems measuring accuracy, latency, and cost.
• Diagnose and mitigate failure modes across the voice stack (transcription errors, hallucinations, prompt brittleness).
• Design and optimize low-latency ML systems delivering a delightful caller experience with empathy.
• Partner with platform/backend engineers to productionize real-time inference and streaming pipelines.
• Collaborate with product/design/frontend/backend teams to integrate voice intelligence into Cresta's platform.
• Mentor engineers and help shape the roadmap for Cresta's voice AI systems.

Skills

5+ years ML in production

Technical leadership

Voice AI

Model evaluation

Realtime systems

Education

Bachelor's degree in CS/Math/ML/AI; Master's/PhD preferred

Tools

TensorFlow

PyTorch

ASR/TTs tech stack

Job description

Lead Voice AI Engineer at Cresta - $270K + Equity in Los Angeles

This is a senior/lead-level IC role at a well-funded, Series C-stage AI company backed by top-tier VCs (a16z, Greylock, Sequoia). The $205K–$270K base, plus equity at this stage, represents compensation well above the median for ML engineering roles in the US — the market median for senior ML engineers with 5–8 years of experience is roughly $175K–$220K, so this range reflects both a premium market and the specialized voice AI domain.

• End-to-end production ML engineering: ASR, TTS, speech-to-speech, agentic LLM systems
• Low-latency streaming inference and real-time system design
• Evaluation frameworks for complex multi-modal AI systems
• Technical leadership and cross-functional influence at a growth-stage startup

These skills — especially voice AI + agentic systems + production LLM evaluation — are among the most in-demand in the current AI job market, with applications at every major tech company, telco, and AI startup.

Green flags: Stanford AI Lab pedigree, impressive client roster (United Airlines, Marriott), experienced CEO with Google AI background, strong VC backing, and a clearly defined scope with real ownership.

Watch for: As a lead engineer at a startup, the role demands both deep technical execution and cross-functional influence — a high-bandwidth expectation. Startup-stage equity vesting schedules and exit timelines should be negotiated carefully. The company has raised $270M, suggesting pressure toward growth or liquidity events in the medium term.

Cresta unlocks the true potential of the customer experience, turning every conversation into a competitive advantage. Cresta's unified AI platform combines conversational AI agents, real-time human agent augmentation, and comprehensive conversation intelligence to drive revenue and efficiency gains across every channel. The world's leading companies, including United Airlines, Cox Communications, and Marriott, use Cresta to power world-class customer experiences every day.

Born from the Stanford AI Lab, Cresta has raised more than $270 million from the world's leading investors, including a16z, Greylock, and Sequoia. Cresta's leadership includes some of the leading minds in AI today. Our CEO, Ping Wu , founded and led Google's Contact Center AI and Vertex AI platforms before joining Cresta to build the future of AI-driven customer experiences.

Over the next few years, AI is going to redefine how people all over the world interact with businesses every day. Come build that future at Cresta.

About the Role

We are looking for a Lead Engineer, AI Agent Voice Experience to help build the next generation of AI-powered voice systems for the contact center. In this role, you will work at the intersection of speech, language, and real-time production systems, improving how AI listens, understands, reasons, empathizes, and responds in live customer conversations.

You will develop and improve machine learning systems that power voice experiences end to end, including automatic speech recognition, turn detection, agentic workflows, voice evaluation, text to speech, speech-to-speech models, and production optimization. You will partner closely with applied researchers, product managers, designers, forward deployed engineers, and platform engineers to ensure model and system improvements translate into measurable customer and business impact.

This role is ideal for someone who is excited by both model quality and production reality: designing rigorous evaluation frameworks, analyzing failure modes, improving latency and robustness, elevating caller interaction experience, and shipping systems that perform reliably at scale in real-time voice environments.

Responsibilities

• Design, train, evaluate, and deploy machine learning systems that power real-time voice experiences, including speech-to-text, turn detection, text-to-speech, speech-to-speech, reasoning, and structured insight generation.
• Improve the quality of voice AI systems through error analysis, data curation, metric design, benchmarking, and iterative model improvement, with a strong focus on real-world performance.
• Build evaluation frameworks for complex voice and agentic systems, measuring metrics such as accuracy, robustness, latency, faithfulness, naturalness, professionalism, task completion, and cost.
• Diagnose and mitigate failure modes across the voice stack, including transcription errors, hallucinations, tool misuse, prompt brittleness, context drift, and multi-step reasoning breakdowns.
• Design, implement, and optimize low-latency ML systems that deliver a delightful caller experience (e.g., backchanneling, focusing on the foreground speaker, interpreting caller emotions, responding with empathy).
• Partner with platform and backend engineers to productionize real-time inference, streaming pipelines, quality monitoring, and continuous model iteration.
• Collaborate cross-functionally with product, design, frontend, and backend teams to integrate voice intelligence seamlessly into Cresta's platform.
• Mentor engineers, contribute to technical strategy, and help shape the roadmap for Cresta's voice AI systems.

Qualifications We Value

• Bachelor's degree in Computer Science, Mathematics, Machine Learning, AI, or a related field; Master's or Ph.D. preferred.
• 5+ years of experience building, evaluating, and deploying machine learning systems in production.
• Demonstrated experience leading fast-moving, highly technical teams. Strong communication skills, with the ability to influence cross-functional decisions and raise the engineering bar.
• Distinctive technical vision for the future of voice AI.
• Strong background in one or more of the following: speech recognition, speech processing, NLP, generative AI, or voice AI.
• Deep experience with model evaluation, benchmarking, error analysis, and quality improvement for production ML systems.
• Solid understanding of transformer-based models, embeddings, retrieval systems, and large-scale training or inference workflows.
• Experience designing and deploying real-time ML systems with strong requirements around latency, scalability, and reliability.
• Experience building data pipelines and tooling for experimentation, measurement, and large-scale quality analysis.
• Ability to work across research and engineering boundaries and translate promising ideas into production-grade systems.

Nice to Have

• Hands-on experience with ASR quality metrics such as WER and task-level evaluation methodologies.
• Experience with RAG systems, agentic workflows, multi-step reasoning systems, or LLM-as-a-judge evaluation methods.
• Familiarity with streaming inference, real-time voice pipelines, or media systems.
• Experience working closely with infrastructure or platform teams on production ML deployment, observability, and reliability.
• Experience in contact center AI, conversational intelligence, or enterprise voice products.

Compensation

We offer a comprehensive and people-first benefits package to support you at work and in life:

• Comprehensive medical, dental, and vision coverage with plans to fit you and your family
• Flexible PTO
• Paid parental leave
• Retirement savings support
• Remote work setup budget or work-from-home stipend
• Monthly wellness and communication allowance
• In-office meal or lunch benefits for onsite employees

Salary Range: $205,000–$270,000 + Offers Equity

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