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Simulation & Evaluation that scales voice and chat AI agents

Compensation: $100K - $200K; Equity: 0.20% - 1.00%; Location: San Francisco, CA, US

Job type: Full‑time | Role: Engineering, Full stack | Experience: Any (new grads ok) | Visa: US citizen/visa only | Skills: Next.js, Python, React, TypeScript, Amazon Web Services (AWS)

The Role

You’ll sit at the intersection of our product and our customers, deeply embedded with the teams building the most advanced voice AI agents in production today. Some days that means writing code. Other days it means shaping evaluation strategy. Every day it means making customers wildly successful.

• Build bridges. We call them that internally: the integrations, connectors, and quality‑of‑life features that make Coval click for a specific customer or use case. You’ll ship fast, validate whether it belongs in the core product, and move on.
• Hunt for friction. You’re in the product every day alongside customers. You’ll find the sharp edges before anyone else and either fix them yourself or work with engineering to eliminate them.
• Shape the product roadmap. You’re the closest person to real customer needs. You’ll translate what you see into what we build. Not by writing tickets, but by forming opinions and advocating for them with prototypes and data.
• Be a voice AI evaluation expert. You’ll develop opinionated eval strategies, learn from the teams building production‑grade agents, and bring that knowledge back into the platform.

The balance shifts depending on the account. Some are deeply technical and you’ll be writing code daily; others need strategic guidance on how to evaluate their agents. You’ll do both.

• You write code in Python and/or TypeScript and you’re comfortable working across APIs, integrations, and customer‑facing technical problems.
• You get energy from customers. Staying up late to ship something that unblocks a customer sounds like a good night, not a bad one.
• You can zoom in on a specific technical problem and zoom back out to see how it fits the bigger picture.
• You move fast but you know the difference between a smart experiment and technical debt that’ll haunt you.
• You’re curious about voice AI and evaluation, or you’re the kind of person who gets obsessive about whatever domain you land in.

You’ll work in Python and TypeScript across API integrations, customer‑facing builds, internal tooling, and evaluation strategy. We invest in tooling that keeps iteration speed high.

Coval is the simulation and evaluation platform for voice AI. We help companies answer the question most can’t: do their voice agents actually work? Not in a demo. At scale, in production, with real users.

Most teams building voice agents are flying blind. They ship a demo that works, deploy it, and discover weeks later that 40% of conversations are failing. No evaluation infrastructure. No way to catch regressions before users do.

We built Coval because we’ve seen this movie before. Brooke led evaluation infrastructure at Waymo, where it takes millions of simulated miles before a vehicle touches a public road. Voice agents need the same rigor. Right now, almost nobody has it.

Nine people, backed by YC, closing six‑figure enterprise deals with Fortune 500 companies, growing revenue 10x year over year. The space is moving fast. We’re at the center of it.

We work in‑person in SoMa, San Francisco. The office is shoes‑off, full of plants, and dog‑friendly. We bike, hike, skate, and run half‑marathons together.

The team comes from Waymo, Zoox, Apple, and Google. We’re hard on our work but never hard on each other. We ship on Sundays because we want to, not because someone told us to. We move at AI speed: what used to take weeks happens in hours.

Our operating principle is “wholesome and unhinged.” We’re relentless about making things happen, but we don’t take ourselves too seriously. If you thrive in ambiguity, move fast, and want to be one of the first people building the sales foundations at a company that’s already closing Fortune 500 deals, this is it.

Voice AI is where the market is going. We’re already there. This is the best time to join.