Senior AI & Ab Initio Engineer UK

Vamstar
Vamstar

Software Engineering, Data Science · Contractor

United Kingdom

Posted on Oct 1, 2026

Title: Senior AI & Ab Initio Engineer - Fintech AI

Location: UK only | Remote with few days onsite per month

Existing Clients: Large FinTech Company

Type: Full-time Contractor

Core responsibilities & objectives

  • Design, build, and migrate Ab Initio workflows to AWS Glue/PySpark.
  • Write production-grade, well-tested Python that processes large volumes of data and documents reliably.
  • Must have hands-on experience using AI coding tools (e.g., Claude) to generate PySpark / AWS Glue code and build test harnesses
  • Own pipeline health: if data is stale, broken, or wrong, it's on you.
  • Work autonomously to project deadlines with minimal hand-holding.

Key qualifications & skills (non-negotiable)

  • 7+ years in backend data-heavy development or data engineering
  • Highly proficient in Python
  • Production experience with Ab Initio deployments and cloud migrations
  • Hands-on experience with large datasets and high-velocity data streams (Kafka, Flink, Spark).
  • Strong with pipeline orchestration tools (Airflow, MLflow, or equivalent).
  • Solid SQL skills (Postgres, Redshift, or Snowflake) and NoSQL experience (DynamoDB, OpenSearch, Elastic).
  • Real experience with LLM workflows: RAG architectures, embeddings/vector DBs, prompt engineering, function/tool calling, observability.
  • Deep understanding of ETL/ELT patterns and data processing at scale.

Preferred background (strong signals)

  • Experience with AWS data stack at scale.
  • Exposure to financial services industries.
  • Built and shipped data, ML and LLM-powered pipelines in production.
  • Has debugged a pipeline and knows why observability matters.
  • Worked in a fast-moving startup where "that's not my job" doesn't exist.

Interested? We're a distributed team solving hard problems that will reshape the fintech industry. If you want ownership, not just tickets, we'd like to hear from you.