Principal Engineer in Technical Fellow Office

ironSource; New York (NY); Hybrid; USD 180,000 - 340,000; Full time

Benefits offered by this job

Health insurance

Employee stock ownership

Competitive retirement plans

Generous vacation and personal days

Parental leave programs

Commute subsidy

Job summary

Unity is seeking a Technical Fellow to solve hard problems at the intersection of AI and large-scale systems. You will lead the design of agentic platforms, productionize workflows, and mentor teams across divisions.

The role focuses on scalable distributed architectures, cutting-edge AI experimentation, and building guardrails for reliable, cost-aware deployments. Strong leadership and cross-team collaboration are essential.

Qualifications

• 10+ years of hands-on engineering in software development, system design, or architecture.
• Applied AI / agentic engineering with modern LLMs and agentic frameworks.
• Production AI systems with evaluation, monitoring, and guardrails.
• Distributed systems and data with streaming/pipeline tech (Kafka, Flink, Spark).
• Cross-functional impact and mentoring engineers toward better technical decisions.

Responsibilities

• Architect & build: Lead the design of critical systems - agentic pipelines, orchestration platforms, and the services around them - running design reviews and contributing hands-on to development.
• Ship agentic systems: Productionize LLM-powered workflows - multi-agent orchestration, tool use, retrieval/knowledge systems, and human-in-the-loop control planes that are reliable, observable, and cost-aware.
• Define quality for AI: Build evaluation harnesses, benchmarks, and automated quality gates that measure and enforce quality in non-deterministic systems, and catch regressions in agent and model behavior.
• Incubate new ideas: Rapidly prototype POCs that validate strategic bets, especially at the intersection of AI and existing platforms.
• Advise & de-risk: Guide complex technical decisions, help teams adopt AI pragmatically, and avoid the failure modes of hype-driven design.
• Surface risks: Identify blind spots, technical risks, and inefficiencies - including the novel risks of autonomous systems - and proactively drive solutions.
• Set the technical bar: Write exemplary code across the ecosystem, and raise the level of engineering through architectural reviews, mentorship, and knowledge sharing across teams.

Skills

Hands-on engineering

System design

Architecture

Applied AI / agentic engineering

Distributed systems

Mentoring engineers

Tools

Kafka

Flink

Spark

Job description

Join the Technical Fellow Office to solve hard, ambiguous problems, set the bar for technical excellence, and shape how the broader engineering organization builds - across teams and beyond our immediate department. You will work at the intersection of large-scale distributed systems and the frontier of agentic AI, architecting the platforms, workflows, and guardrails that let autonomous and human-in-the-loop AI systems do real work at scale.

If you want to work where cutting-edge AI meets production-grade engineering - and influence how an entire division builds - this is that role.

What You'll Do

• Architect & build: Lead the design of critical systems - agentic pipelines, orchestration platforms, and the services around them - running design reviews and contributing hands‑on to development.

• Ship agentic systems: Productionize LLM-powered workflows - multi‑agent orchestration, tool use, retrieval/knowledge systems, and human‑in‑the‑loop control planes that are reliable, observable, and cost‑aware.

• Define quality for AI: Build the evaluation harnesses, benchmarks, and automated quality gates that measure and enforce quality in non‑deterministic systems, and catch regressions in agent and model behavior.

• Incubate new ideas: Rapidly prototype POCs that validate strategic bets, especially at the intersection of AI and existing platforms.

• Advise & de‑risk: Guide complex technical decisions, help teams adopt AI pragmatically, and avoid the failure modes of hype‑driven design.

• Surface risks: Identify blind spots, technical risks, and inefficiencies - including the novel risks of autonomous systems - and proactively drive solutions.

• Set the technical bar: Write exemplary code across the ecosystem, and raise the level of engineering through architectural reviews, mentorship, and knowledge sharing across teams.

What We're Looking For

• 10+ years of hands‑on engineering in software development, system design, or architecture.

• Applied AI / agentic engineering: Real experience with modern LLMs and agentic frameworks - prompt/context engineering, tool use, RAG, orchestration, and evaluation - including the sharp edges (latency, cost, reliability, non‑determinism, safety).

• Production AI systems: A track record of taking AI/ML‑driven features from prototype to production with proper evaluation, monitoring, and guardrails.

• Distributed systems & data: Strong background in scalable, fault‑tolerant services and in streaming/pipeline technologies (Kafka, Flink, Spark).

• Cross‑functional impact: Ability to drive alignment and technical decisions across teams, and to mentor engineers toward better technical decision‑making.

Mountain View, SF/Bay: $227,900 - $341,900

Bellevue, Seattle, NYC, Remote CA: $202,800 - $304,200

Rest of US: $179,500 - 269,300

This range reflects the anticipated base salary for this position. Beyond base salary, this role may be eligible for equity awards and participation in our company incentive plans (such as annual discretionary bonuses or sales commissions). The final offer amount will depend on several factors, including geographic location and the candidate's relevant experience, professional background, and skill set.

Benefits

At Unity, we want our team members to thrive. We offer a wide range of benefits designed to support well‑being and work‑life balance.

Please note: Benefits eligibility, specific offerings, and coverage vary based on the country and employment status.

While specific benefits vary, here are some of the ways we strive to take care of our eligible team members globally:

• Comprehensive health, life, and disability insurance
• Commute subsidy
• Employee stock ownership
• Competitive retirement/pension plans
• Generous vacation and personal days
• Support for new parents through leave and family‑care programs
• Office food snacks
• Mental Health and Wellbeing programs and support
• Employee Resource Groups
• Global Employee Assistance Program
• Training and development programs
• Volunteering and donation matching program

Life at Unity

Unity [NYSE: U] is the world's leading game engine, powering play for more than 3 billion consumers each month. The top mobile games in the world, the most played PC indie titles, the most innovative console games, and virtually all of the top XR and Web Games are developed, deployed, and grown in Unity. Unity also enables teams across industries like automotive, manufacturing