Join 39 AI

Build warmer, more expressive AI products with us.

We're looking for people who are excited about AI, product, and creation - and want to build the next generation of AI products with us.

Locations

United States

Palo Alto, CA

Japan

Tokyo

Global

Remote

Company Introduction

39 AI Inc. is a Bay Area-founded, AI-native startup building more natural and emotionally resonant AI product experiences. We explore more authentic, expressive, and companion-like ways for people and AI to connect.

Our current products include the AI audio product FishAudio, AI chat products, and several new AI product directions still in incubation. The team is flat, direct, and fast-moving. We encourage people to speak up, own ideas, and turn them into shipped work quickly.

The team is young, sincere, relaxed, and creator-minded, with a strong anime, comics, and gaming culture, and deep creator roots. We do not set limits around degrees, compensation, equity incentives, office location, or growth paths. We are looking for people who are deeply excited about AI, products, creation, and new things to explore the next generation of AI products with us.

Benefits & Culture

What we offer

We care about speed, craft, and giving people the support they need to do their best work.

Visa sponsorship

We sponsor on a case-by-case basis depending on role and location. Your recruiter will walk through the details on the first call.

We ship fast

Voice AI is moving in weeks, not quarters. We hold a high bar on quality and design and we still ship faster than anyone in the category.

We back each other

Open, direct, low-ego culture. We tell each other the truth and we make each other better.

Highly Competitive Compensation

Highly competitive base salary and meaningful equity.

Health coverage

Platinum medical, dental, and vision coverage.

Office meals

Daily lunch and dinner in office.

Unlimited PTO

Unlimited PTO.

Best-in-class setup

Best-in-class hardware.

Careers

Open Roles

Brand and Creative Designer

Own visual direction and creative execution across campaigns, launches, social media, product visuals, and the long-term brand system.

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Voice Experience Designer

Own the quality bar, acquisition pipeline, and catalog curation for natural-sounding voices on Fish Audio.

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AI Systems Engineer

Design and optimize high-performance algorithm engines for in-house large model development and real-world AI applications.

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GPU Infrastructure SRE

Own the reliability and operations of large-scale GPU infrastructure for model training and production inference.

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Voice Agent Platform Engineer

Build the architecture, engine, SDKs, and product surfaces for Fish Audio's open realtime voice Agent platform.

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Full-Stack Engineer

Own the full path from database design, APIs, and web frontends to deployment, directly taking AI products from zero to one.

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Solution Engineer

Support B2B client onboarding, third-party vendor integrations, and hands-on technical issue resolution across external systems and our internal platform.

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Ghostwriter

Write viral posts that make the internet hear the future of voice AI, turning model launches and demos into stories people cannot help but share.

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Demand Gen Marketer

Build Fish Audio's first B2B marketing function, turning developer interest into repeatable enterprise pipeline and revenue.

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Sr Business Development Representative

Own pipeline generation for Fish Audio, reaching technical founders, product leaders, engineering teams, and enterprise buyers building with voice AI.

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