Product Engineer

About Cardinal

Cardinal (trycardinal.ai) is the AI-native outbound sales platform replacing the SDR-and-GTM-engineer stack that companies cobble together today with Apollo, Outreach, Clay, and a few engineers gluing them all together.

We’re a YC W26 company. In our first few months we’ve grown to $80K+ MRR, with 50+ YC companies and a growing roster of post-Series-A startups running their outbound on us. We’ve raised over $5M from Audacious, Burst Capital, and YC, and we’re targeting $10M ARR by mid-2026.

We’re a small, dense, design-obsessed team. The bar for engineering taste, product instinct, and aesthetic quality is very high — if you’ve ever opened Linear or Attio and thought “why doesn’t every B2B tool feel like this,” that’s the bar.

The Role

As a Product Engineer at Cardinal, you’ll work on the surfaces our customers — founders, GTM leaders, sales engineers — live in every day. That includes our sequence and enrollment system (per-lead customization, multi-sender, conditional branching), the Cedar agent layer (the embedded AI agents that draft, research, and enroll on behalf of the user), and the eval and observability tooling that lets customers trust an AI to run their pipeline.

Cardinal is a system of action sitting on top of every GTM data source — CRMs, enrichment APIs, LinkedIn, intent signals, website visitor data. Our job is to make all of that feel like one beautifully designed product, not a plumbing project. You’ll work directly with the founders, ship to production every week, and have an outsized influence on what the product becomes.

We’d love to meet you if you:

Philosophy: You’re your own worst critic. You don’t ship at 90%. You don’t just file the bug — you fix it. You move fast without confusing fast for sloppy.

Product intuition: You can tell the difference between a UI that feels good and one that doesn’t, and you can articulate why. You think from first principles about user workflows, not feature checklists.

GTM context : You’ve worked at a sales-adjacent company — an outbound tool, a CRM, a sales intelligence platform, a revenue-tech startup — or you’ve been the technical person at a startup who actually built and ran the outbound motion yourself. You don’t need to be a sales expert, but you should immediately understand why a “step 3 reply detection” bug or a “lead enrichment timeout” matters to a customer. If words like sequence , enrollment , ICP , intent signal , deliverability , and sender rotation don’t make you glaze over, we want to talk.

Bonus points if you:

• Have founded a company, been an early engineer at a YC-stage startup, or shipped a product 0→1
• Have built or worked at a GTM/sales/CRM/enrichment tool — Apollo, Outreach, Clay, Attio, HubSpot, Salesforce, Gong, Common Room, or anything in that orbit
• Are a power user of GTM tools yourself — you’ve actually run outbound, written sequences, and fought with deliverability
• Have worked on real-time collaborative interfaces, agent UIs, or eval/observability tooling
• Care about design at the level of Linear, Attio, Raycast, or Vercel — and have shipped UIs at that quality bar

This is an in-person role at our SF office. We’re early stage, which means working hard and moving quickly. Apply if that excites you.