Principal Engineer, Fin AI Agent

About This RoleAI processing…

Key Responsibilities

• 1
  Partner at the strategic pillar level. You'll have broad context across work streams and use that to inform technical strategy and investment priorities. What should we care about? Where should we invest? Where do you need to step in? These are your decisions.
• 2
  Spin up 0-to-1 work streams. Bring together engineers who've never worked as a team, disambiguate the problem space, build momentum under aggressive timelines, set high expectations, and drive execution.
• 3
  Execute on the most ambiguous, highest-stakes problems. You're hands-on. You write code, you ship features, you're deep in the weeds. We've seen too many Principal Engineers who are brilliant but too far from execution to be effective here.
• 4
  Lead experimental work at the AI frontier. Run your own A/B tests, do prompt engineering, build evals, and calibrate accuracy, cost, and latency for LLM-powered features. Much of what we're building are new paradigms for customer-facing software.
• 5
  Shape long-term technical strategy through execution. Your hands-on work informs the architecture. You're simultaneously building and thinking about what needs to change about how we build products — data models, system design, the shift from GUI-first to agent-first interfaces.
• 6
  Work across the full stack in an AI-first development environment. Every engineer has Claude Code with unlimited tokens and a sophisticated ecosystem of MCP servers, skills, and shared context. You'll push the boundaries of what's possible with AI-assisted development and help shape how the entire engineering org works.
• 7
  Raise the bar for the people around you. Give direct, actionable feedback that changes outcomes. We don't need someone who mentors juniors on the basics — we need someone who can accelerate and grow the senior and staff engineers around them.

Requirements

• Operated at real scale and has builder energy. You've likely spent time at companies operating at significant scale — the kind of environment where you've seen what large-scale distributed systems actually look like in production. But you also have startup DNA: urgency, resourcefulness, a bias toward building over discussing.
• AI fluency. You're actively experimenting with AI-assisted development, pushing the boundaries of what's possible, and forming opinions about how it changes the way teams build software. This matters more than any specific stack experience.
• Deep technical depth with breadth. You can go deep into the weeds on at least one technical domain, but you also navigate complex multi-team systems with ease. In conversation, you move fluidly from business context to technical strategy to implementation details.
• Communication as a superpower. You can explain to leadership why a technical investment matters, align multiple teams around a complex project, and then walk an engineer through the gnarly implementation details. This role lives and dies on your ability to communicate across every level.
• Extreme autonomy. You partner with the Engineering Director on where you think the pillar needs to go next. You identify problems, form convictions, and act on them. If you're the kind of engineer who waits to be told what to work on, this isn't the right role.
• Critical thinking about the business. You understand what Fin is optimizing for and translate that into technical decisions. Which work streams need investment? Where are we falling behind? What should we defund to go harder somewhere else? You think at this level naturally.
• At least ~10+ years of experience , with significant time as a technical leader driving complex projects across multiple teams and stakeholders.
• Stack agnostic. We use Ruby on Rails, React (migrating from Ember), and AWS. But AI tools increasingly abstract the stack — what matters is your ability to learn, build, and operate effectively with tools like Claude Code. If you're great with a high-level programming language and fluent with AI-assisted development, you'll be productive fast.

Perks & Benefits