About Cartesia

Our mission is to build the next generation of AI: ubiquitous, interactive intelligence that runs wherever you are. Today, not even the best models can continuously process and reason over a year-long stream of audio, video and text—1B text tokens, 10B audio tokens and 1T video tokens—let alone do this on-device.

We're pioneering the model architectures that will make this possible. Our founding team met as PhDs at the Stanford AI Lab, where we invented State Space Models or SSMs, a new primitive for training efficient, large-scale foundation models. Our team combines deep expertise in model innovation and systems engineering paired with a design-minded product engineering team to build and ship cutting edge models and experiences.

We're funded by leading investors at Index Ventures and Lightspeed Venture Partners, along with Factory, Conviction, A Star, General Catalyst, SV Angel, Databricks and others. We're fortunate to have the support of many amazing advisors, and 90+ angels across many industries, including the world's foremost experts in AI.

About the Role

Cartesia is seeking a customer-obsessed Customer Success Lead to build our entire post-sales customer function from the ground up. You'll work directly with our most innovative customers to ensure they unlock maximum value from our voice AI technology, while creating the scalable systems and processes that will power our customer success organization as we grow.

This is a highly strategic, 0-to-1, founding role for someone who thrives at the intersection of customer advocacy, revenue growth, and operational excellence. You’ll be responsible for designing the complete customer journey from onboarding through renewal and expansion, building world-class enablement content, and creating feedback loops that directly influence our product roadmap. Over time, you’ll hire and manage a team of CSMs, and you’ll play a key role in driving cross-sell and upsell in our largest accounts.

Your Impact

• Own the entire post-sales customer journey – onboarding, activation, adoption, renewals, and expansion – to maximize customer value from voice AI across both PLG and enterprise motions.

• Build customer success infrastructure from 0-to-1 – segmentation, coverage model (high-touch vs scaled/tech-touch), playbooks, prompting guides, onboarding sequences, QBR/EBR templates, and scalable support systems.

• Drive cross-sell and upsell in strategic accounts – identify expansion opportunities from product usage and org mapping, partner with Sales to shape expansion strategy, and help grow NRR across our largest customers.

• Deeply understand customer pain points and friction across the journey, design strategies to streamline their experience, and build seamless feedback loops directly into Product and Engineering.

• Establish metrics for success – define KPIs and health scores to measure onboarding, adoption, retention, and expansion; build dashboards and rhythms to review them.

• Create world-class enablement content and thought leadership – training materials, documentation, best-practice playbooks, and insights that establish Cartesia as the authority on voice AI and drive self-serve success for PLG users.

• Collaborate with GTM on activation and growth strategies – partner with Sales, Growth, and Marketing to improve product-led growth, inform packaging and pricing, and turn successful customers into advocates and references.

• Embed with strategic accounts – understand their use cases and technical environment, remove blockers, lead success planning, and drive deep product adoption across teams and geographies.

• Bridge technical and customer needs – translate between customers and Product/Engineering, surfacing relevant pain points, usage patterns, and feature requests that materially improve the product and roadmap.

• Stand up our post-sales tooling – help select and implement CS tools (CRM workflows, CS platform, in-app engagement, knowledge base) to support a scalable customer success motion.

• Build and lead the function – as the motion becomes repeatable, hire, coach, and manage a team of CSMs; define roles, operating cadences, and career paths as the organization scales.

What You Bring

• 8+ years of professional experience, including 4+ years at a high-growth B2B startup in a customer-facing role (Customer Success, Account Management, Solutions, or similar).

• Experience working with B2B SaaS products; experience at an AI, ML, developer tools, or data/infra company is a strong plus.

• Ideally, experience building or scaling a customer success or post-sales motion from scratch – designing processes, playbooks, and metrics rather than just operating an existing one.

• Demonstrated ability to drive retention and expansion in mid-market or enterprise accounts (e.g., increasing NRR, owning or heavily influencing renewals, identifying and executing on cross-sell/upsell plays).

• Customer obsession – you get energy from talking to customers, understanding their workflows, and will run through walls to ensure their success.

• Excellent communicator – exceptional written and verbal skills; you can translate technical concepts into clear narratives and build alignment across executives, operators, and engineers.

• High-impact self-starter – comfortable operating with minimal guidance, thriving with full ownership over ambiguous, cross-functional workstreams.

• Exceptional problem-solving skills – you excel at taking complex, undefined problems from 0 to 1, structuring solutions, and driving decisions with data.

• Highly organized with a bias toward action – you value velocity, learning, and shipping, while maintaining systematic execution and follow-through.

• Excitement for our mission – genuinely curious about the future of voice AI and energized by what we’re building at Cartesia.

Nice to Have

• Technical degree (Computer Science, Engineering, Mathematics, etc.)

• Customer success, onboarding, or account management experience at B2B SaaS companies

• 2 years at a top tier consulting, investment banking, or private equity firm

• Background building customer education programs or thought leadership content

• Financial modeling and quantitative analysis experience

• Experience with customer success tools and scaling customer-facing teams

• Professional background in AI/ML or enterprise software

What We Offer

🍽 Lunch, dinner and snacks at the office

🏥 Fully covered medical, dental, and vision insurance for employees

🏦 401(k)

✈️ Relocation and immigration support

🦖 Your own personal Yoshi

Our Culture

🏢 We’re an in-person team based out of San Francisco. We love being in the office, hanging out together, and learning from each other every day.

🚢 We ship fast. All of our work is novel and cutting edge, and execution speed is paramount. We have a high bar, and we don’t sacrifice quality or design along the way.

🤝 We support each other. We have an open & inclusive culture that’s focused on giving everyone the resources they need to succeed.