Ingo (Dipl.-Inform.) Grebe-Founder and Owner
Check rate
Experience
Development of a practice management software for appointment scheduling including online booking
Reactive Systems
For a specialized diabetes center in Hamburg, I designed and independently implemented a custom practice management software. The goal was to develop a fully integrated solution for managing appointments, patients, and practitioners - including online booking for patients.
Tasks and responsibilities:
- Architecture, concept, and full development of the web application
- Implementation of the user interface with Angular, SCSS, and Bootstrap
- Development of the backend with ASP.NET Core, REST APIs, and MS SQL
- Implementation of a role-based user concept for parallel use by medical staff
- Integration of an online booking system for patients
- Carrying out all tests and close coordination with the medical staff
- Agile work according to Scrum, including iterative planning and direct clarification of requirements with doctors and employees
Results and impact:
- The software is used daily by up to 10 employees at the same time and has noticeably simplified appointment management in the practice
- Online booking by patients was successfully introduced and is used regularly
- The application stands out for its intuitive usability and reliable performance
- High satisfaction from the practice management and the team thanks to a practical, tailored implementation
Further development of a web application for vehicle inspections
GTÜ - Gesellschaft für Technische Überwachung
As part of a long-term project at GTÜ (Gesellschaft für Technische Überwachung mbH), I am involved as a full-stack developer in the further development of a modern web application that digitally supports the execution of vehicle inspections such as periodic vehicle inspections (HU) or safety inspections (SP). The application is a central part of the company's latest software generation and is used across Germany.
Tasks and responsibilities:
- Implementation of new features on the frontend and backend with Angular and ASP.NET Core
- Identification and resolution of performance issues on the server side
- Development and optimization of logging mechanisms for better traceability and error analysis
- Continuous refactoring of legacy code to ensure long-term maintainability
- Contribution to architecture decisions and technical further development of the overall system
- Close collaboration with QA, DevOps, and other development teams in an agile environment (Scrum/Kanban mix)
Results and impact:
- Active contribution to resolving critical backend performance issues as a member of the performance team
- High customer satisfaction through fast and reliable implementation of new requirements
- Continuous familiarization with complex system parts and stable delivery of high-quality code
PWA for recording working hours and CMS for managing employees and times
Reactive Systems
For a construction company from Wetzlar, I planned and fully developed a progressive web app (PWA) for mobile time tracking as well as a web-based CMS for managing employees, construction sites, and working hours. The goal was to provide a user-friendly solution that works reliably both online and offline.
Tasks and responsibilities:
- Architecture, concept, and full implementation of the application
- Development of the frontend with Angular and SCSS, with special focus on offline capability
- Implementation of the backend with ASP.NET Core, Entity Framework Core, and MS SQL
- Development of a CMS for managing employees, construction sites, and time entries
- Integration of synchronization logic for offline use of the PWA
- Close coordination with the owner and employees for a practical implementation
- Iterative work according to Scrum with regular feedback and direct testing in daily work
Results and impact:
- More than 40 employees use the app daily on construction sites - even without an active internet connection
- The software was easily accepted by all employees thanks to its intuitive usability
- The owner was extremely satisfied with the fast implementation and the tailored functionality of the solution
- The application has sustainably digitized and simplified time tracking in the company
Mobile app for carrying out and logging COVID-19 rapid antigen tests
Reactive Systems
- Technologies: Angular, Bootstrap, HTML, NativeScript, SCSS, TypeScript
Further development of a web application for submitting doctor invoices
Reactive Systems
- Technologies: AngularJS, Bootstrap, CSS, HTML, Java, JavaScript, SCSS
Web application for creating and publishing ad campaigns
Reactive Systems
- Technologies: Angular 5, ASP.NET, Facebook API, Google APIs, HTML, JavaScript, C#
Further development of a web application for submitting doctor invoices
Reactive Systems
- Technologies: AngularJS, Bootstrap, CSS, HTML, JavaScript, SCSS
Development of a website, API, and database for presenting properties
Reactive Systems
- Technologies: Angular 4, ASP.NET Core, Bootstrap, C#, Entity Framework Core
Further development of software for reward shops
Reactive Systems
- Technologies: AngularJs, ASP.NET WebAPI, C#, CSS, HTML, JS, Entity Framework, SQL
Development of software for particle measurement in clean rooms
Reactive Systems
For an engineering office from Langen, I developed custom software that maps the entire process of particle measurement in clean rooms digitally - from managing measurement tasks, rooms, and limit values to mobile execution and follow-up of the measurements. The application supports both office and field use and was specially tailored to the requirements in cleanroom technology.
Tasks and responsibilities:
- Planning and full implementation of the application, including architecture design
- Development of a back office system with ASP.NET MVC and Entity Framework
- Implementation of the user interface with AngularJS, Bootstrap, and classic web technologies (HTML, JS)
- Implementation of the mobile application for offline particle measurements on site
- Development of a synchronization logic for transferring measurement data to the central server
- Close cooperation with the owner and specialist staff for continuous improvement
- Agile work according to Scrum with iterative deliveries and practical validation
Success and impact:
- Daily use of the software by more than 10 employees - both in the field and in the office
- Offline functionality enables reliable execution of measurements directly at the customer's site
- The application was quickly accepted by the whole team because of its intuitive operation
- Significant improvement in efficiency and data quality in particle measurement and follow-up
Development of a facial recognition software
Reactive Systems
- Technologies: AngularJs, ASP.NET WebAPI, C#, CSS, HTML, JS, Neurotechnology SDK, WCF
Further development of a geoinformation system
Reactive Systems
- Technologies: Angular, ASP.NET WebAPI, HTML, JavaScript, Material Design, SCSS
Development of a reporting system
Reactive Systems
- Technologies: ASP.NET, C#, SQL Reporting Services
Industry Experience
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Experienced in Information Technology, Healthcare, Automotive, Professional Services, Construction, and Advertising.
Business Area Experience
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Experienced in Information Technology, Product Development, Marketing, Accounting, and Business Intelligence.
Summary
Since 2007, I have been working with great passion as a software developer and software architect in desktop and web development. As a consultant, I help improve the quality of my clients' software. My specialty is the development of web-based business applications. I build backends in C# using the Microsoft .NET Framework as services or APIs. They usually run in the cloud and in the local intranet. The frontends are developed in JavaScript/TypeScript, HTML, and (S)CSS with Angular and can be used by browser-capable systems. My strengths lie in independent and responsible thinking and action.
Since 2007, I have been working with passion as a software developer and software architect in desktop and web development. As a consultant, I improve the quality of my clients' software. By founding Reactive Systems, I want to take responsibility for larger projects and support junior developers.
Skills
- Angular And Angularjs
- Asp.Net Core
- Asp.Net Mvc And Webapi
- Bootstrap
- Entity Framework
- Jquery
- Nativescript
- Wcf
- Winforms And Wpf
- C#
- Fdo
- Javascript
- Html
- Razor
- (S)Css
- Sql
- Sql Server
- Sql Reporting Services
- Typescript
- Azure Devops
- Git
- Jira
- Npm And Nodejs
- Team Foundation Services
- Visual Studio
- Webstorm
Languages
Education
Dipl.-Inform. · Computer Science
Statistics
Experience
Global Experience
Expertise
Profile
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