Senior Harness Engineer
Level inferred from job title
Job description
A hands-on senior engineering role on FICO's engineering team focused on Harness Engineering: building the guides, feedback loops, guardrails and shared context that steer AI coding agents toward correct, maintainable, production-grade output. The role owns whole harness subsystems and sets standards other engineers build to.
At a glance
- Work mode
- Remote
What you'll do
- Design, build, deploy, and support core components of the harness - the guides, feedback loops, guardrails, and shared context that turn raw model capability into production-grade engineering.
- Own and evolve feedforward guides - agent instruction files, reusable skills, architectural rules, reference docs, and codemods - and drive team-wide standardisation.
- Build feedback sensors - custom linters, static analysis, structural and architecture-fitness tests, verification loops, and LLM-as-judge reviewers - that catch issues automatically before they reach human reviewers.
- Own quality gating and release criteria for agent-produced work, defining authority boundaries for what agents may merge unaided and escalation rules for what must route to a human.
- Establish LLM testing infrastructure and evaluation approaches that ensure AI-generated output meets quality and safety thresholds; apply consumer/contract testing (e.g. Pact) where service integration reliability matters.
- Run the steering loop - when an agent repeats a mistake, engineer a control so it can't happen again - and treat repository knowledge (docs, specs, context) as the system of record, fighting drift with continuous garbage collection.
- Decide where each control runs in the path to production - fast checks pre-commit, more expensive checks post-integration, and continuous sensors that scan for drift outside the change lifecycle.
- Improve observability into agent work and track measures such as cost per merged PR, time-to-merge for agent-assisted PRs, review velocity relative to PR size, defect escape rate, and agent-PR survival rate.
- Partner with product and platform teams to turn specifications and acceptance criteria into enforceable controls.
- Serve as a source of technical expertise and mentor engineers across teams in harness practices and the effective, responsible use of AI tools.
What we're looking for
- Bachelor's/Master's in Computer Science or related disciplines, or relevant commercial experience in software architecture, design, development, and testing.
- Seasoned software engineer with experience in large, complex codebases and a strong foundation in architecture and design; cares deeply about testing and maintainability.
- Hands-on experience with AI coding agents (e.g. Claude Code, Codex, or similar) and a well-developed feel for where they succeed and fail.
- Proven ability to build engineering tooling across a modern stack - linters and static analysis, CI/CD pipelines, containerised build/test environments, and instrumentation/observability - plus familiarity with agent instruction conventions such as AGENTS.md.
- Experience with spec-driven development, context engineering, agent orchestration, fitness functions, and developer-platform work.
- A systems mindset - rather fix the environment than fix one output - and the ability to encode "what good looks like" into mechanical, repeatable rules.
- Judgement about when to reach for deterministic, computational controls (type checkers, linters, structural/architecture-fitness tests) versus inferential, LLM-based ones (AI code review, LLM-as-judge), and understanding of the cost, speed, and reliability trade-offs between them.
- Experience owning quality-gating processes and defining release criteria to ensure engineering standards are consistently met.
- Working knowledge of the security surface unique to autonomous agents - prompt injection, tool/permission scoping, sandboxed execution, and audit trails for agent actions - and how to design least-privilege guardrails around them.
- Experience with consumer/contract testing approaches (e.g. Pact) to validate service integrations across distributed systems.
- Excellent communication skills; able to articulate design with architects and drive standards across teams.
Your team
engineering team
Team at the heart of a new discipline: Harness Engineering, engineering the environment that steers AI coding agents toward correct, maintainable, well-architected output.
Benefits
An inclusive culture strongly reflecting our core values: Act Like an Owner, Delight Our Customers and Earn the Respect of Others.
The opportunity to make an impact and develop professionally by leveraging your unique strengths and participating in valuable learning experiences.
Highly competitive compensation, benefits and rewards programs that encourage you to bring your best every day and be recognized for doing so.
An engaging, people-first work environment offering work/life balance, employee resource groups, and social events to promote interaction and camaraderie.
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About FICO
A leading global analytics software company, helping businesses in 100+ countries make better decisions.
FICO (NYSE: FICO) is a leading global analytics software company, helping businesses in 100+ countries make better decisions. FICO makes a real difference in the way businesses operate worldwide, including credit scoring, fraud detection and security, and lending.
Mission
Help businesses use data to improve every choice they make, using advances in artificial intelligence, machine learning, optimization, and much more.
Key facts
- Analytics software
- FICO® Scores are used by 90 of the top 100 US lenders.
- 4 billion payment cards globally are protected by FICO fraud systems.
- 3/4 of US mortgages are approved using the FICO Score.
- Among the world's top 100 software companies by revenue.
- Helps many of the world's largest banks, insurers, retailers, telecommunications providers and other firms.
What they value
- Act Like an Owner
- Delight Our Customers
- Earn the Respect of Others