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Posted May 26, 2026

Senior Software Engineer, Machine Learning – Simulations Platform

Job Description: • Build, maintain, and optimize Upstart’s next-generation machine learning and simulation platform, enabling increased scale, performance, and confidence in decisioning • Develop high-quality software applications that enable machine learning models to be applied to the ever-evolving needs of the business • Enable the modernization of our serving infrastructure, reducing inference latency to just a few seconds for our most complex models • Design and contribute to our simulation systems to more accurately reflect production environments, reducing simulation cost and enabling broader usage across teams • Communicate closely with cross-functional partners from ML, Engineering, Product, and Data Engineering teams, keeping all stakeholders informed • Mentor engineers across the team, sharing expertise on distributed systems, MLOps, and scalable architecture Requirements: • 6+ years of software engineering experience including several building and contributing to in-house Machine Learning Platforms • Experience building and maintaining backend software services and APIs • Proficiency with some or many of the following: Python, Kotlin, Databricks, and AWS • Exhibits a growth mindset - you’re not afraid to pick up new technologies that are best for the task, and learn from others. • Ability to quickly comprehend and reiterate complex requirements from product or engineering leadership and translate those to both technical and non-technical stakeholders • Track record of successfully mentoring and developing other engineers around you while seeking out and appreciating constructive feedback • Familiarity with model serving technologies like Ray, simulation platforms, experimentation frameworks • Proficiency with Flask, FastAPI, Metaflow, MLflow, gRPC, Kafka, Spark/PySpark, ETL/ELT, Redshift (or similar) • Excellent quantitative reasoning skills with interest in working at the intersection of engineering and machine learning • Strong sense of ownership and accountability for the quality and timely delivery of work • Proven ability to effectively analyze and solve complex problems • Excellent written and verbal communication skills with stakeholders, peers and product owners • Ability to thrive both in self-directed work environments and in collaborative settings, contributing positively to team dynamic Benefits: • Competitive Compensation (base + bonus & equity) • Comprehensive medical, dental, and vision coverage with Health Savings Account contributions from Upstart • 401(k) with 100% company match up to $4,500 and immediate vesting and after-tax savings • Employee Stock Purchase Plan (ESPP) • Life and disability insurance • Generous holiday, vacation, sick and safety leave • Supportive parental, family care, and military leave programs • Annual wellness, technology & ergonomic reimbursement programs • Social activities including team events and onsites, all-company updates, employee resource groups (ERGs), and other interest groups such as book clubs, fitness, investing, and volunteering • Catered lunches + snacks & drinks when working in offices