OverviewEpsilon's transactional data products turn purchase and card-transaction signals into governed datasets that our audience, measurement, and client reporting teams build on. We're hiring a Senior Principal Engineer to own the quality and reliability of those datasets on our lakehouse platform.
This is a hands-on individual contributor role. You'll be in the pipelines and in the SQL, accountable for data that goes directly into client work - where correctness and timeliness are product requirements. It suits someone who is happiest close to the data, unbothered by a messy real-world domain, and treats doing the same fix twice as a bug.
- Empower with accountability: You own your data products end to end - ingestion through publication - and the engineering standards the rest of the team builds against.
- Innovate with purpose: You'd rather eliminate a class of problem than resolve an instance of it.
- Work together to win together: This role reports to the Senior Director, Data Product Engineering.
Responsibilities- Quality you can prove. Build the automated QC layer - completeness, distribution, referential integrity, anomaly detection - and turn the signal into a small number of alerts people actually trust.
- Reliability you own. Diagnose failures and discrepancies across large, high-cardinality data, and set freshness and correctness expectations you can demonstrate you're meeting.
- Toil that disappears. Replace recurring manual operations with automation and self-service tooling, and make compute proportional to what actually changed rather than to the size of the dataset.
- A platform that keeps improving. Evolve the Spark and SQL pipelines you own - tune refresh strategy and cost, retire the scaffolding that has outlived its purpose, and make each new source cheaper to onboard than the last.
- A higher bar. Set the standards other engineers follow - shared libraries, automated testing, code review, declarative deployment - and mentor the engineers and analysts around you.
QualificationsWhat you'll bring with you- 10+ years hands-on with production data, across data engineering, data operations, or data platform work
- Expert SQL, including performance tuning where a bad query plan costs hours and real money rather than seconds, plus strong production Python (PySpark preferred)
- A track record designing data quality, validation, monitoring, or reconciliation systems that measurably reduced defects or manual effort
- Real accountability for production batch pipelines, not only experience building them
- Large-scale distributed platforms (Databricks, Spark, or equivalent) and relational or MPP warehouses (Greenplum, Postgres, Snowflake, Redshift, or similar)
- Software engineering practice applied to data work: version control, code review, automated testing, CI/CD
- Comfort with messy, high-cardinality data - matching and deduplication included - and healthy skepticism toward data that looks too clean
- The ability to explain how an upstream change ripples into a downstream product to people who aren't engineers
- Bachelor's degree in a technical field, or equivalent practical experience
Why you might stand out from other talent- Transaction, payments, card, retail POS, loyalty, or retail measurement data experience
- Delta Lake or equivalent, governed catalogs, incremental ingestion, and cluster or warehouse cost tuning
- Workflow orchestration at scale (Airflow, Databricks Jobs) and containerized deployment
- PII handling, pseudonymized identifiers, or work in regulated or clean-room environments
- Lightweight internal tooling (Flask or similar) for operational interfaces
Additional InformationCompensation Range: USD $132,800.00 - USD $246,600.00/Annually. This is the pay range the Company believes it will pay for this position at the time of this posting. This role may also be eligible for bonus or incentive compensation. Consistent with applicable law, compensation will be determined based on the skills, qualifications, and experience of the applicant along with the requirements of the position, and the Company reserves the right to modify this pay range at any time. Temporary roles may be eligible to participate in our freelancer/temporary employee medical plan through a third-party benefits administration system once certain criteria have been met. For regular roles, the Company will offer medical coverage, dental, vision, disability, 401k, and paid time off. The Company anticipates the application deadline for this job posting will be 11/12/2026.
