Ed-Fi source code is available as open source, under the Apache License, version 2.0. You can access the source code in GitHub here:
Access to some tools and materials require you to obtain an Ed-Fi Community account, which is simple and easy to do. You can get started at https://www.ed-fi.org/create-an-account/
You can view issues in Ed-Fi tracker here, and contribute to tickets once you have an Ed-Fi account, by logging in here.