Senior Machine Learning Engineer

Salary: USD 180K-200K/annual; DOEbeehiiv is the all-in-one newsletter and creator platform powering the next generation of media companies and independent voices. We help creators and businesses launch, grow, and monetize newslettersnow serving tens of thousands of publishers and reaching hundreds of millions of readers monthly. With $20M ARR, 100% YoY growth, and a newly expanded product suite (ad network, website builder, paid tiers), were entering our next phase of hypergrowth.We are seeking a motivated Senior Machine Learning Engineer to design, build, deploy, and own production ML systems that power core parts of beehiivs ad network, content intelligence, and growth ecosystem.Youll work across the entire ML lifecycleproblem framing, feature engineering, large-scale data processing, model training, evaluation, deployment, monitoringand partner closely with Data Engineering, Product, and Platform teams.This role is ideal for someone who wants to work on real-time optimization, high-dimensional modeling, vector embeddings, and ML-driven automation, all while shipping to production continuously.The successful candidate will likely not have expertise across all of these areas, but rather deeper mastery in one of them (Data Science, Research & Development, MLOps, ML Engineering, etc.) with passable knowledge of the others. We value your unique perspective, and the day-to-day is highly dependent on the skills you bring.Ideally, you have:47 years building ML systems end-to-end in productionDeep experience with Python and common ML Libraries (pandas, NumPy, PyTorch, XGBoost, scikit-learn)Strong understanding of supervised learning, ranking models, anomaly detection, embeddings, optimization, and feature engineeringStrong SQL and performance instincts (ClickHouse experience a huge plus)Ability to analyze extremely large datasets (potentially billions of events) efficientlyPractical knowledge of statistics, experimental design, and investigative analyticsKnowledge of the NLP ecosystem (Huggingface, SentenceTransformers, etc) and underlining Transformers architectureFamiliarity with Airflow or similar orchestration toolsNice-to-Have:Experience building models around digital ads, marketplaces, recommender systemsExperience with entity resolution, especially in graph databases (Neo4j)Experience with vector databases (Chroma, Pinecone, Qdrant, etc.)Experience shipping ML components to production on Cloud through Docker, ECS, EKSExpertise in MLOps (MLFlow, Kubeflow, Feature Stores, etc), double points for experience in setup and maintenance on AWSExperience with single GPU inference systems (CUDA, MPS)Experience with multi-objective optimization or constrained solversPrior startup experience or ownership-heavy engineering rolesWhat you'll be responsible for:Your core responsibilities will center on our ad network and high-volume, real-time systems.Ad Network Optimization:Build and improve models for CTR prediction, publisher ad acceptance probability, publisheradvertiser matching, content quality classifiers, ad creative optimization, etcDevelop multi-stage optimization systems that assign ad opportunities using xarray tensors, constrained solvers, and multi-objective reward functionsImprove inventory estimators, cold-start models, and dynamic feature pipelinesMaintain and improve sentence-transformer embedding pipelines forpublications, tags, campaigns, advertisers, and user behaviorOwn vector similarity search, clustering, topic modeling, and publication-level semantic analyticsPersonalization algorithms to optimize publisher experience within the ad network interfaceCreating lightweight microservices on AWS for model inferenceDeveloping and hosting APIs using Python FastAPIResearch and implementation of new methods, models, and frameworks as the complexity of the ad network increasesDepending on your expertise and company priorities, you will have opportunities to contribute to the following initiatives.ML Platform EngineeringDesign reusable training/serving pipelines using PyTorch, XGBoost, Airflow, Kubernetes/EKS, Docker, and vector databasesDesign MLOps architecture for artifact versioning and storage, back testing, ML centric CICD pipelines, etcImprove offline evaluation: log-loss, WMAPE, ROC AUC, calibration curves, multi-class softmax metricsInstrument production models with monitoring, drift detection, and alertingSubscriber ProfilesEntity resolution of subscriber-level data based on advertiser pixel tracking.Creating a dense representation of subscribers and publications behind basic content categorization that can be used in downstream modelsAdvanced segment cohorts for better ad targeting and publisher reportingHydrate profiles with external data sources to create stronger representationsWhy this role might be for you:Join a fast-growing new team that prioritizes velocityHigh impact and high visibilityYou can take loosely defined objectives and develop appropriate proposals and solutionsYou have or are excited to work in a fast-paced startup environment.Youre excited about conducting research and experimenting with new technologiesYou can disagree and commitWhy this role might not be for you:Not a traditional 9-to-5 position.Need to manage multiple priorities and stakeholders.Must be comfortable with rapid iteration and frequent context switching.High expectations for both speed and quality.Must navigate complex organizational dynamics.Why beehiiv?Bias towards action:Our first impulse is to act. We dont get bogged down in unnecessary processes or bullsh**t. Perfection is the enemy of progress.Ownership mentality:This company is ours. We go the extra mile because thats what owners do. Every day, people step up to take on tasks outside of their responsibilities and do whatever it takes for us to succeed.Building is in our DNA:We are obsessed with improving every aspect of our platform (and ourselves). Whether its our product, support, or partnerships, we never stop working to improve it.We answer to our users:Nothing matters more than serving our users. If our users fail, we fail.Ego comes second, but winning comes first:We put our egos aside to work collaboratively and build something special. It doesn't matter who's idea or who's vision, we're here to create the best outcome. We're here to win.We'll take care of you:Competitive salaryStock OptionsHealth, Dental, and Vision Insurance401(k) employer matchUnlimited PTO (mandatory 10 days per year minimum)Annual in-person team retreatUnlimited book budgetMonthly Wellness Days (every third Friday of the month)

Salary : $107,000 - $146,900