Senior Data Engineer: Legacy DB Modernization & Migration

Ajentica; United States; Remote; USD 140,000 - 190,000; Full time

Job summary

Ajentica is leading a backend data rebuild for a behavioral health platform with ~20 years of debt. The role focuses on re-architecting the data layer from MSSQL to a clean Postgres model, building pipelines and current-state ERDs, and enabling scalable, well-documented data infrastructure that supports future growth.

You will reverse engineer legacy logic, migrate data, and design a robust, maintainable schema while aligning with Azure Data Factory workflows.

Qualifications

• 4-7 years of data engineering experience.
• Strong relational data modeling experience with production database redesign/migration.
• Proven ability to reverse engineer undocumented systems.
• Hands-on MSSQL/SQL Server experience.
• ETL pipelines in Python.

Responsibilities

• Reverse engineer stored procedures, transformation logic, and schema behavior.
• Map actual vs intended system behavior.
• Create current-state ERDs from scratch.
• Design a clean, maintainable target data model (Postgres).
• Deconstruct and rationalize the transformation layer; remove dead logic.
• Develop Python-based ETL pipelines and orchestrate with Azure Data Factory.
• Migrate data and validate end-to-end after migration.
• Document and ensure traceability across components.

Skills

MSSQL/SQL Server

Python ETL

PostgreSQL

Azure Data Factory

.NET integration

Reverse engineering

Tools

PostgreSQL

Azure Data Factory

.NET

Job description

Ajentica is leading a backend data rebuild for a behavioral health platform with ~20 years of debt. The role focuses on re-architecting the data layer from MSSQL to a clean Postgres model, building pipelines and current-state ERDs, and enabling scalable, well-documented data infrastructure that supports future growth.

You will reverse engineer legacy logic, migrate data, and design a robust, maintainable schema while aligning with Azure Data Factory workflows.