Mountain View, California, USA Staff / Principal Research Scientist - USA

Realtime TTS-2 is the #1 model on Artificial Analysis and the fastest TTS in the world of its class. Watch the launch video Staff / Principal Research Scientist - USA Mountain View, California, USA

About Inworld

Inworld is a research lab of top researchers and engineers, building the world’s top-ranked realtime voice models.

Today our models are the #1 ranked realtime voice models in the world. They are used to power the largest consumer-facing AI applications available, across categories like health, fitness, learning, therapy, companions, customer experience and media; representing 100s of millions of end users. Our work spans areas like research and development of state-of-the-?

We’ve raised more than $125M from Lightspeed, Section 32, Kleiner Perkins, Microsoft’s M12 venture fund, Founders Fund, Meta and Stanford, among others. Our technology has powered experiences from companies such as NVIDIA, Microsoft Xbox, Niantic, Logitech Streamlabs, Wishroll, Little Umbrella and Bible Chat. We’ve also been recognized by CB Insights as one of the 100 most promising AI companies globally and have been named one of LinkedIn’s Top 10 Startups in the USA.

Who We're Looking For

A year ago, reliably working agentic systems barely existed. Nobody has a decade of experience here. So we're not screening for a resume template — we're looking for strong people from varied backgrounds who learn fast, thrive in ambiguity, and can show us what they've built, broken, and understood.

Experience We Find Useful

You don't need all of this. But you need enough to make a case.

• Foundation models : training, new architectures, RL, reward modeling, scaling
• Evaluation : benchmarks, eval loops, quality measurement, LLM-as-judge, failure analysis
• Frontier topics : multimodal models, agents, tool use, test-time compute, world models
• Published research at ICML, ICLR, NeurIPS, EMNLP, ACL, or AAAI
• PhD in ML/NLP — or equivalent practical experience you can point to
• Public work : non-trivial AI side projects, interdisciplinary experiments, open-source contributions
• Full-stack research ownership : you frame the question, run the experiments, write the paper, ship the result

If you learned through building, competitions, or collaborations outside academia, that counts. We care about evidence, not credentials.

Who Thrives Here

• You don’t need a roadmap to start walking; you’re comfortable picking a direction and building the map as you go
• You believe research isn't finished until it’s shipped. You have a bias for impact over purely academic output
• You don't just ship code; you obsess over the why. You’re the first to question an approach if you think there’s a better way to solve the core problem
• You aren't satisfied with "the PM said so." You thrive on deep context and want to understand the fundamental logic behind every decision we make

What Working Here Is Like

We hand you unclear problems and expect you to make them clear. We value researchers who say "I don't know yet" and then design the experiment that finds out. We treat evaluation as a first-class research product, not a box to check before launch. Impact comes before publications though we support sharing work that moves the field forward. Your work should be visible. Flat structure, fast iterations, minimal process theater.

We believe in the power of in-person collaboration to solve the hardest problems and foster a strong team culture. We offer relocation assistance and look forward to you joining us in our Mountain View office.

The base salary range for this full-time position is $270,000 - $500,000+ bonus + equity + benefits.