Senior Machine Learning Systems Engineer, Ads ML Experience Platform

Details

Reddit is a community of communities. It’s built on shared interests, passion, and trust, and is home to the most open and authentic conversations on the internet. Every day, Reddit users submit, vote, and comment on the topics they care most about. With 100,000+ active communities and approximately 126 million daily active unique visitors, Reddit is one of the internet’s largest sources of information.

We are building the next generation of ML research tools and agentic AI platforms that power machine learning development across Reddit. Our mission is to accelerate the Ads ML lifecycle – from experimentation and training to deployment, evaluation, and autonomous operations – through scalable platform services, intelligent automation, and developer-centric tooling.

Our team owns critical platform capabilities including offline ML experimentation systems, production training orchestration frameworks, ML lifecycle automation and, agentic ML frameworks that enable faster model iterations.

We are looking for an experienced engineer with deep expertise in large-scale distributed systems, ML platforms, and emerging agentic architectures to help define and build the foundational tooling for the next generation of our machine learning devX tooling.

Responsibilities

• Design and build large-scale offline ML experimentation platforms that enable reproducible research, model development, evaluation, and promotion workflows.
• Develop production-grade training orchestration frameworks supporting distributed training, hyperparameter optimization, model evaluation, and automated retraining.
• Build infrastructure for experiment tracking, metadata management, lineage, artifact versioning, model registries, and reproducibility.
• Partner with ML engineers and researchers to improve experimentation velocity and operational efficiency.
• Build automated workflows for model promotion, rollback, compliance validation, and continuous evaluation.
• Design and build an agentic AI execution platform supporting autonomous and human-in-the-loop workflows, including multi-agent orchestration, memory/context systems, and scalable workflow infrastructure.

Requirements

• 5+ years in infrastructure/platform engineering or large-scale distributed systems.
• 2+ years of hands-on experience building and operating production ML infrastructure, developer SDKs, platform APIs, or self-service AI tooling.
• Experience building workflow orchestration systems, developer platforms, or large-scale automation frameworks.
• Experience with distributed data processing systems such as Spark, Flink, Ray, or equivalent technologies.
• Experience with modern orchestration and workflow technologies such as Kubeflow, Argo, Airflow, or similar frameworks.
• Experience building offline ML experimentation platforms, model registries, experiment tracking systems, or training orchestration frameworks.
• Experience building and operating agentic AI systems, including multi-agent orchestration, autonomous workflows, and agent communication/runtime frameworks (e.g., MCP, A2A, and orchestration systems) is a strong plus.
• Experience running end-to-end model development and iteration cycles at scale is a plus.

Location & Work Arrangement

• Remote - United States. Reddit offers flexibility to work remotely in any country where it has a physical presence and its offices are open if you live nearby.

Pay Transparency & Benefits

• Base salary range: $216,700 - $303,400 USD (U.S.-based postings). Final offers vary by skills, experience, and other factors.
• Eligible to receive equity in the form of restricted stock units; depending on the position, may also be eligible to receive a commission.
• Benefits for U.S.-based employees include medical, dental, and vision insurance, 401(k) program with employer match, generous time off, and parental leave.

Additional Notes

• In select roles and locations, interviews may be recorded, transcribed and summarized by AI; candidates may opt out prior to scheduled interviews.
• Reddit is an equal opportunity employer and provides reasonable accommodations for applicants with disabilities.