Add REI3 to Money, Budgeting & Management

README.md

@@ -1097,6 +1097,7 @@ _See also: [awesome-sysadmin/IT Asset Management](https://github.com/awesome-fos
 - [Kresus](https://kresus.org/) - Open source personal finance manager. ([Demo](https://kresus.org/en/demo.html), [Source Code](https://github.com/kresusapp/kresus)) `MIT` `Nodejs`
 - [OnTrack](https://github.com/inoda/ontrack) - A simple app to track spend and set goals. `MIT` `Ruby/React`
 - [PartKeepr](https://www.partkeepr.org) - PartKeepr is an electronic part inventory management software. It helps you to keep track of your available parts and assist you with re-ordering parts. ([Demo](https://demo.partkeepr.org/), [Source Code](https://github.com/partkeepr/PartKeepr)) `GPL-3.0` `PHP`
+- [REI3](https://rei3.de/home_en/) - Open source, expandable Business Management Software. Manage tasks, time, assets and much more. ([Demo](https://rei3.de/demo_en/), [Source Code](https://rei3.de/download_en/)) `MIT` `Go`
 - [SilverStrike](https://silverstrike.org/) - Personal finance management made easy. ([Demo](https://demo.silverstrike.org/), [Source Code](https://github.com/agstrike/silverstrike)) `MIT` `Python/Django`
 - [StockazNG](https://dev.sigpipe.me/dashie/StockazNG) - Asset Management System. `MIT` `Python`
 - [Tabby](https://github.com/bertvandepoel/tabby) - A tool to manage shared expenses across friends, such as restaurant costs or food delivery, without requiring everyone to create an account. Includes email reminders and tracks who has (re)paid what. `AGPL-3.0-only` `PHP`