Senior Data Engineer

Company: Epsilon Strategy & Insights
Location: Schiller Park
Posted on: March 21, 2026

Job Description:

The Epsilon Activation Delivery Platform team builds the core framework and connectors powering our audience activation business. We are a small, high-impact team of engineers operating at massive scale—trillions of user events flow through our pipelines every month. By building and maintaining integrations with major advertising players (Meta, Google, Amazon) and Connected TV publishers (LG, Samsung), your work directly connects our data ecosystem to the biggest platforms in the world. Who does this role report to and who will they collaborate with on a day-to-day basis? This role reports to the Engineering Director and collaborates closely with fellow data engineers, product managers, and partner teams. You will participate in design reviews, code reviews, and the end-to-end delivery of critical business features in a highly collaborative environment. Why would a top candidate evaluating multiple opportunities want this job? Operate at True Scale: Work in a high-volume data environment where your pipelines will process and route trillions of records monthly. Work with Modern Data Tech: Get hands-on with an innovative big data stack using Spark, Scala, Python, AWS EMR, and Databricks. See Your Impact: Your code will directly enable our business to interface with the world’s largest tech, social media, and CTV platforms. Own the Solution: We are a small team, which means you will have the autonomy to take complex problems from ingestion and specification all the way through to production. What You’ll Achieve • Core Contribution: Write robust, scalable, and maintainable code using Spark (Scala/Python) and SQL to build out our core framework and data pipelines. • Pioneer AI-Assisted Engineering: We are on the cutting edge of AI adoption. You will leverage tools like Cursor and Amazon Q Developer to accelerate coding, debugging, and testing. Youll also actively participate in experimenting with the latest developer workflows for agentic, AI-assisted development, helping define the future of how our team builds software. • Scale Integrations: Build, maintain, and optimize the high-concurrency data connectors that feed external publishers and ad networks. • Optimize & Troubleshoot: Dive deep into complex data processing routines on EMR and Databricks. You will actively troubleshoot production issues, tune SQL queries, and solve for performance bottlenecks in a distributed environment. • Team Mentorship & Quality: Participate in rigorous code reviews, help enforce engineering best practices, and mentor mid-level/junior engineers to elevate the teams overall codebase. • Continuous Improvement: Build and maintain automated production processing routines that fit seamlessly into our existing scheduled cloud infrastructure. Who You Are • What you’ll bring with you: o B.S. in Computer Science, Computer Engineering, or a related field. o 5 years of professional experience on a development team building and maintaining big data pipelines. o Deep, hands-on expertise in Apache Spark and distributed computing concepts. o Strong programming proficiency in Scala and/or Python. o Fluent SQL skills with the ability to ingest complex use cases, refactor code, and tune queries for massive datasets. o Proven experience working within cloud environments (AWS preferred) and managed platforms like Databricks or EMR. o Ability to troubleshoot production issues autonomously and own a problem to the end. o Excellent communication skills to interface with internal stakeholders, ask the right questions, and translate business requirements into technical solutions. • Why you might stand out from other talent: o Experience in the AdTech/MarTech space, specifically programmatic advertising, identity resolution, or audience activation. o Familiarity with orchestration tools (e.g., Airflow). o Experience building and optimizing data integrations with external REST APIs at high concurrency. o Exposure to streaming technologies (Kafka) or NoSQL databases.

Keywords: Epsilon Strategy & Insights, Downers Grove , Senior Data Engineer, Engineering , Schiller Park, Illinois