Senior Product Engineer

October 7, 2026

Job Type: Full Time

Job Location: Remote, U.S.

Job Overview

We’re looking for a Senior Product Engineer who owns problems end to end — from an ambiguous idea through a shipped, maintained solution — and lifts the engineers around them while doing it. You’ll join a collaborative team building the platforms that help some of the world’s largest companies manage complex indirect spend.

This role is defined by ownership of outcomes. You’ll take direction on what needs solving, but you’ll own how it gets solved: shaping the approach, deciding what ships within the time available, making sound design decisions, and seeing the work all the way into production. Working across our Ruby on Rails and JavaScript/TypeScript stack, you’ll be a technical example for the team — mentoring engineers, raising the quality bar, and helping shape how we build.

We build with AI at the center of our workflow. You’ll work alongside AI coding agents every day: shaping problems and writing specs and plans they can execute against, then reviewing and verifying what they produce. The judgment you bring to design, scope, and correctness matters more here, not less.

You’ll also be expected to learn our business deeply. Our clients are procurement and finance teams at major global companies, and the best decisions here come from understanding why their world works the way it does.

At Fine Tune, our core values of honesty, dedication, and vigilance foster an environment of trust, open communication, and inclusivity where everyone can do their best work. If you care about your craft, want to keep getting better, and thrive in a team that’s building something meaningful — let’s talk.

This is a full-time, salaried, remote position. Candidates must be US citizens and located in the United States.

Responsibilities and Duties

• Own Problems & Deliver:
  • Own projects from problem definition through delivery and ongoing maintenance, including problems that start ambiguous or loosely defined
  • Compare viable approaches and recommend one with clear reasoning
  • Cut scope to fit the time available, and know when to cut and when to escalate
  • Produce clean, well-tested implementations across Rails and JavaScript/TypeScript; design data models and APIs other engineers build on
• Design & Decide:
  • Design systems within our architecture — decompose problems into components with clear responsibilities, boundaries, and interfaces
  • Design for failure as well as for the happy path
  • Weigh tradeoffs and make the reasoning behind consequential decisions clear
  • Debug complex, cross-cutting issues systematically and get to root cause
• Build AI:
  • Use AI coding agents as a core part of how you deliver: decompose work into well-defined specs and plans, direct implementation, and iterate on the results
  • Own every line that ships, whoever or whatever wrote it. Understand it well enough to explain it, predict its behavior, and change it
  • Review AI-generated code with deliberate thoroughness for correctness, security, and fit with our architecture
  • Help improve our AI development workflow, including the context, conventions, and automated gates that make agent output reliable
• Verify & Protect:
  • Choose the right verification strategy for the work and verify behavior against intent, not just against the implementation
  • Apply established security patterns and handle sensitive client data appropriately
  • Spot security risk before it ships
• Lead & Mentor:
  • Mentor engineers; give thoughtful code reviews that raise the team’s bar by example with well designed and scalable architecture
  • Evaluate implementations you didn’t write for correctness, security, and fit
  • Drive technical decisions and build consensus across the team without relying on authority
  • Identify and lead improvements to code, architecture, testing, and process
• Collaborate & Grow:
  • Partner with product and QA to turn business needs into well-scoped work delivered iteratively
  • Work in fixed cycles with a small team that owns shaped work end to end
  • Communicate decisions, tradeoffs, progress, and risks clearly across the team
  • Contribute to architecture and design discussions and to team learning initiatives like book clubs and mentoring

What We’re Looking For

• Craft
  • 5+ years of professional product or software engineering experience, or …