# A senior engineer joins a public fintech with 412 DAGs from four years of accumulation: 80 mission-c

Canonical URL: <https://datadriven.io/problems/a-senior-engineer-joins-a-public-fintech-with-412-dags-from-2f6906a8>

Domain: Pipeline Design · Difficulty: medium

## Problem

A senior engineer joins a public fintech with 412 DAGs from four years of accumulation: 80 mission-critical with no contracts, 332 orphans with no identifiable consumers, custom Python every ingestion path, one Airflow owning every DAG. The CTO wants both a target architecture and a deprecation plan. Apply the entire advanced tier: shared layers with named contracts, every undercurrent visible as tooling, split orchestrators at team boundaries, managed ingestion for commodity SaaS, and a deprecation queue tracked in the catalog.

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