Excel/CSV to PostgreSQL Import Scripts

We need a developer to build reusable scripts that import structured Excel and CSV files into PostgreSQL. These scripts should be repeatable, deterministic, and idempotent where practical, so they can run on future files with the same structure without further development. You will read files, validate structure, clean and transform data, map fields to the PostgreSQL schema, handle relationships and foreign keys, manage duplicates and existing records, and report invalid or skipped rows with clear logs and error messages. We will provide the schema, field mappings, business rules, and sample files. The main deliverable is the importer scripts for each supported format.