Machine Learning Research Engineer

Iris Labs; Cambridge (MA); On-site; USD 120,000 - 193,000; Full time

Benefits offered by this job

Healthcare coverage

Annual incentive program

Retirement benefits

Job summary

Iris Labs seeks a talented Machine Learning Research Engineer to innovate and apply ML methods for foundational psychological tools. The role involves working with world-class scientists and engineers on state-of-the-art AI research and applications.

The candidate should have broad expertise in ML, reinforcement learning from human feedback, supervised fine tuning, and computational sciences, and thrive in a fast-moving startup environment with a passion for impactful human-AI technologies.

Qualifications

• Masters level (or above) in CS, ML or AI preferred.
• Strong foundation in ML, deep learning, and NLP.
• Publications in top ML/NLP venues are a bonus.
• Experience deploying LLM-powered apps in production (PyTorch, vLLM, LangGraph).
• Proficiency in Python and ML data pipelines; good evaluation protocols.

Responsibilities

• Design, develop, and deploy ML-powered apps using LLMs for wellbeing challenges.
• Collaborate with psychological experts to translate insights into computational frameworks.
• Advance context engineering, agentic AI, and learning from human feedback.
• Build scalable data collection, labeling, training, and deployment pipelines for LLM-based systems.
• Support integration of ML systems into real-world applications with measurable outcomes.
• Communicate findings to a multi-disciplinary audience.

Skills

ML fundamentals

NLP

Reinforcement learning

Education

Master's degree in CS/ML/AI

Tools

PyTorch

vLLM

LangGraph

Job description

The Company

Iris Labs, Inc. is a privately held, early-stage company pioneering the use of artificial intelligence to transform how people navigate life’s challenges and wellbeing. We are creating a platform that empowers people to build a life they are proud of and fulfilled by. We bring together psychology, product, design, engineering, and machine learning to build digital experiences that are engaging, trustworthy, and genuinely helpful.

Iris Labs is backed by Flagship Pioneering, an innovation enterprise that conceives, creates, resources, and builds companies that invent breakthrough technologies that transform the world. Flagship has created over 100 groundbreaking companies since 2000, including Moderna.

TheRole

Iris Labs seeks a talented Machine LearningResearch Engineer.The successful candidate willinnovate,developand apply machine learning (ML) methods to create foundational psychological tools. This position is ideal for someone with broad expertise in machine learning, reinforcement learning from human feedback, supervised fine tuning, and computational sciences who is looking to join a very dynamic and innovative environment and pioneer the next frontier of innovation, application, and human-aiinteractions enabledbystate-of-the-artmodels.A successful candidate should have a passion for buildingtechnologies that enable others to maximize their potential.

Working at Iris Labs, you will have the opportunity to work with world-class scientists, engineers, and researchers who work on cutting-edge ai research and applications.

KeyResponsibilities

• Design, develop, and deploy ML-powered applications thatleveragelarge language models (LLMs) to address complex challenges in wellbeing.
• Collaborate with psychological experts and translate interdisciplinary insights into computational frameworks.
• Help advance the state of the art in context engineering, agentic AI and learning from human feedback.
• Build scalable pipelines for data collection, labeling, training, and deployment of LLM-based systems.
• Support the integration of ML systems into real-world applications with measurable outcomes.
• Communicate findings to a multi-disciplinary audience.

Professional Experience & Qualifications

• Masters level (or above) experience in CS, ML, and AI is preferred, but can be relaxed for exceptional candidates.
• Strong foundationin machine learning, deep learning, and natural language processing (NLP).
• Publications at top ML / NLP venues such as NeurIPS, ICML, ACL and EMNLP are a bonus.
• Proven experience deploying LLM-powered applications in production environments, includingexpertisein frameworks likePyTorch,vLLM, andLangGraph.
• Proficiencyin Python and tools for ML development,large-scaledatapipelines and pre-processing, andstandardevaluationprotocols.
• Self-motivated and comfortableworking in ambiguous, fast-moving environments with evolving goals.
• Excellent communication and presentation skills.
• Must be able to think independently and work collaboratively.
• Experience in a previous startup is a plus.

About Flagship Pioneering

Flagship Pioneering invents and builds platform companies, each with the potential for multiple products that transform human health, sustainability and beyond. Since its launch in 2000, Flagship hasoriginatedmore than 100 companies. Many of these companies have addressed humanity’s most urgent challenges: vaccinating billions of people against COVID-19, curing intractable diseases, improving human health, preempting illness, and feeding the world by improving the resiliency and sustainability of agriculture.

Flagship has been recognized twice on FORTUNE’s “Change the World” list, an annual ranking of companies that have made a positive social and environmental impact through activities that are part of their core business strategies and has been twice named to Fast Company’s annual list of the World’s Most Innovative Companies. Learn more about Flagship at www.flagshippioneering.com.

At Flagship, we accept impossible missions to enable bigger leaps. Our core values guide us through uncertainty and toward lasting impact.

We are an equal opportunity employer

All qualified applicants will be considered for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, protected veteran status, or any other characteristic protected by law.

We recognize that great candidates often bring unique strengths without fulfilling every qualification. If you have some of the experience listed above but not all, please apply anyway. We are dedicated to building diverse and inclusive teams and look forward to learning more about your background and interest in Flagship.

The salary range for this role is $120,000 - $192,500. Compensation for the role will depend on a number of factors, including a candidate’s qualifications, skills, competencies, and experience. Iris Labs, Inc. currently offers healthcare coverage, annual incentive program, retirement benefits and a broad range of other benefits. Compensation and benefits information is based on Iris Labs, Inc.’s good faith estimate as of the date of publication and may be modified in the future.