About Cinder

Cinder is the mission-critical infrastructure that keeps the world's most important digital platforms true to what they stand for. The internet has always been abused by bad actors, and AI is making it exponentially worse, driving fraud, abuse, and manipulation at a scale and speed no human team can fight alone. Cinder gives platforms one command center to fight back: to write and enforce policy, deploy AI agents against abuse in real time, investigate threats, file NCMEC reports, and prove their safety programs are working.

Our customers are some of the largest internet platforms in the world. The decisions made in our software directly determine what stays up, what comes down, and how users are treated.

We're a small, fast-moving team backed by Accel and Y Combinator. We care about being intentional, direct, and deeply focused on solving real customer problems.

Why this role

Cinder's product surface is expanding fast: new agent-facing workflows, multiple product lines, and a growing brand and GTM footprint. We're building out design to match, and we're looking for a second senior designer to own significant surfaces end to end.

You'll operate as a co-lead and thought partner with our current designer. You'll take full ownership of your own surfaces, shape design direction and craft standards together, and give each other real, two-way critique. We expect you to get fluent in Cinder fast, so you can operate independently and make your own thoughtful decisions on Cinder design. This is a chance to help define how design works at Cinder from an early stage, not just execute inside an existing structure.

What you'll work on

• Own end-to-end design for assigned surfaces, from framing the problem to shipped UI, working directly with product and engineering.

• Run discovery with product: talk to Trust & Safety customers and users, and turn what you hear into design direction and Linear tickets an engineer can pick up and build from.

• Prototype at high fidelity to pressure-test flows and align engineering before build starts.

• Contribute to and help maintain our design system as the product scales.

• Take on design work beyond core product when it counts. This could include brand, GTM, decks, website, and marketing. We're a small design team, so we're looking for real appetite to proactively own broader design projects, not just tolerate them.

• Sit in critique with our design lead. Give and take direct feedback, and help hold the bar on craft.

What we're looking for

• Strong visual and graphic design craft: the eye to judge quality, and the ability to produce clean work without leaning on AI tools.

• 6+ years designing software at senior to staff level, with real depth on technical products built for expert users.

• Expert in Figma: wireframing, flows, prototyping, and production-grade delivery.

• Fluent with AI coding agents (Cursor, Claude, Codex) for designing and prototyping, not just experimenting with them.

• A high tolerance for ambiguity. You can create your own clarity and make calls without a finished PRD or research.

• Proactive by default. You flag and fix design debt before anyone asks you to.

• Comfortable talking to customers directly and turning what you hear into product opportunities.

• Strong systems thinker. You see how changes in one part of the product affect the rest

• Experience building or maintaining a design system, including component libraries or patterns.

• Front-end fluency: comfort prototyping in code and picking up interim engineer-designer work.

• Experience designing SaaS, especially multi-product platforms and information-dense interfaces.

• Empathy for the trust & safety problem space.

Nice to have

• Experience designing for AI or agentic products.

• Motion design skills or a sense for delightful detail.

• Comfort with website CMS builders for brand and marketing support.

• Appetite to help build design team culture and rituals from scratch: crits, standups, lunch-and-learns.

• A design background or lineage different from what's already on the team. We're intentional about building that kind of range.

Location & Benefits

We're based in NYC and would relocate the right person for this role. We believe in working together in person and hold at least two all-company events per year. We offer health, vision & dental benefits, a 401(k) plan with employer matching, fully paid commuter benefits, and a fully stocked office with paid lunch and dinner.