About the project (description, duration, stage)

Join Neurons Lab as a Data Engineer on a new engagement with a regulated UK & Ireland credit and lending company. The client has lifted data from multiple business entities into a newly centralized, anonymized data lake, but lacks the data-engineering depth to make it trustworthy and analytics-ready: current pipelines were assembled quickly (partly AI-assisted), and the descriptive statistics cannot yet be validated or reproduced.

You put that foundation on solid ground so the Data Science Lead can model on it with confidence — validate and re-engineer the pipelines, build the harmonization / semantic layer across entities, enforce data quality and lineage, and prepare clean, feature-ready datasets.

This is a foundational data-engineering role on a regulated data estate; data protection and reproducibility are the primary constraints on every decision.

Full-time engagement preferable.

What you'll actually do (example tasks)

- Reproduce a descriptive-statistics report end-to-end so any figure traces back to raw source — closing the gap the client admitted (numbers they can't currently defend).

- Profile and reconcile differing source schemas across acquired entities: map differing field names, types, encodings and business definitions for the same concept into one conformed model.

- Build dbt staging intermediate mart models with tests; codify the harmonized definitions the Data Science Lead specifies.

- Write Great Expectations suites (null / range / uniqueness / referential checks) and wire them into the pipeline so bad data fails loudly rather than silently corrupting analysis.

- Implement entity / identity resolution (deterministic + fuzzy matching) where there is no clean shared key for the same customer or account across sources.

- Implement and verify anonymization / pseudonymization (hashing / tokenization / k-anonymity)



and evidence that re-identification risk is controlled for the client's IT / compliance team.

- Optimize Spark / Glue jobs over tens of millions of rows — partitioning, file formats (Parquet), incremental loads, cost control.

- Orchestrate with Airflow / Step Functions; build repeatable, scheduled pipelines rather than one-off scripts.

- Prepare clean, documented, feature-ready datasets for the PD / delinquency models.

- Document runbooks so the offshore team can operate the pipelines and handover takes days, not weeks; help scope onboarding of the remaining (Ireland + additional) sources.

Skills

- Strong SQL and Python for large-scale data processing

- AWS data stack: S3, Glue, Lake Formation, Athena / Redshift, EMR / Spark, Step Functions / Airflow

- Data modeling & semantic layer (dbt or equivalent); dimensional modeling

- Entity resolution / record linkage across heterogeneous sources

- Data-quality & testing frameworks (Great Expectations, dbt tests) and data lineage

- Anonymization / pseudonymization techniques and their analytical trade-offs

- Big-data processing (Spark) with performance and cost optimization at scale

- Clear written / verbal English; documents for handover and works well with a distributed team

Knowledge

- GDPR fundamentals as applied to anonymized / pseudonymized financial data and UK / EU data residency

- AWS Well-Architected (Analytics, Security) for BFSI

- Awareness of credit / risk data structures and what downstream modeling consumers need — a plus

Experience

- 4+ years in data engineering, with strong AWS + Spark / SQL at scale

- Demonstrated experience harmonizing / integrating data across multiple source systems

- Experience building validated, reproducible pipelines in a regulated environment (BFSI, healthcare, government) — strong plus

- Comfortable stepping into a messy, partly-built data estate and bringing it up to standard

- Comfortable as the sole or lead data engineer on a small (3–4 person) delivery pod

📌 Data Engineer (Madrid)
🏢 Neurons Lab
📍 Madrid