If you keep copying thousands of values between CSV columns, I can turn your agreed rules into a small reusable Python program. It fills empty destination cells, keeps existing destination values, leaves the original file unchanged and creates a change log.
This package covers one UTF-8 CSV structure, up to 10,000 data rows, 100 columns, 10 MB and 10 source-to-destination column pairs. Comma, semicolon and tab separators are supported. You receive the source code, a configuration file for your columns, a fictional example and a short guide. Python 3.10 or later must already be installed. No paid API or subscription is required.
The working sample has passed 10 automated checks, including a real run on 10,000 rows. A dry run previews the change counts. Results go into a new folder, so an existing output is not overwritten. The log records row numbers and column names without copying cell values.
Before ordering, send a non-confidential sample of 10-20 rows, the column pairs and an example of the expected result. We will confirm the scope, delivery method and payment before work starts. Delivery is 3 days after scope agreement and funded order. One revision of the agreed mapping rules is included.
This package does not include Excel files, CRM or API integration, server setup, Python installation or arbitrary data cleaning. The demonstration uses fictional data. I use AI-assisted development and check the resulting program against the agreed examples.