Modification to existing ASP.NET website

General information for the business: Cloud software providing work tracking
Kind of development: Customization of existing program
Description of requirements/functionality: I have an existing Web App that updates an entity's data (in an SQL back end) when a user performs a particular action on the front end, and this is done by making a call to a C# API Controller.

This project is to enable the application to keep a timestamped history of those actions, and I envisage it meaning changes to:
- The code first model of the entities, creating a new table for the transactions
- The api controller, to log the transactions
- The migrations, to update the back end database with the new table when deployed
Extra notes: The code for the Web App is kept in a private GitHub repository. I will create a new branch for this work, and grant you access to commit to that branch - so you'll need a GitHub account.