a Senior Mobile Developer
an interim tech lead
an interim CTO
I am a software engineer with many years of experience for Mobile (iOS / Flutter) and web, including knowledge of the "full-stack" of web technologies for frontend and backend services.
As a developer and technical lead I managed various projects for well-known, multinational clients (e.g. Daimler AG, Mercedes-Benz Museum, Autostadt / Porsche AG, ImmobilienScout24, BKK VBU) and lead teams of varying sizes (between 5 to 15 persons). Having worked in a usability agency for many years and being extremely self-motivated with a strong interest for „usable“ products which are balanced with a technical design for a long term use.
„Before you were there, no one in VBU knew how to take an app productively. You have an immense footprint in that you identify with the cause like an internal and yet manage to bring your external expertise to all levels - either by coaching colleagues or giving advice to me. Thanks for that!“Roman Scheffler (Head of Platform and Applications, BKK VBU)
„René is a superbly gifted, problem-solving engineer in the realms of web and mobile applications, and (code) quality assurance. He is a delight to work with and I recommend him most highly.“Matthias C. Schroeder (UX Lead / Sr. UX / Interaction Designer, former CEO of UCDplus GmbH)
Support for the realisation of (mobile) applications in the field of eHealth and the digitalisation of the health care system. Implementation of an app for insured persons of the BKK VBU to get in contact with your health insurance company and to be able to complete tasks. In addition to the app (flutter), the complete stack was realized on the basis of Kubernetes and various individual services. These services were connected to established standard tools of health insurance companies (e.g. 21c of BITMARCK) to provide data for policyholders.
Expanding the key skills bouncing, calming, encouraging, doing laundry and getting along with little sleep.
Maintained an app for a large multinational corporation of nonalcoholic beverage concentrates which was used by a large group of sales representatives in Europe. The app was highly reactive, connected to Salesforce backend and used Couchbase lite for local persistence. I migrated the app and related frameworks to Swift 4.2 and gave architectural decisions and recommendations.
Working in an English speaking environment I supported with test-driven implementation of a complete new feature for multi provider registration. Did the architectural decisions and recommendations, gave a workshop about introducing testability for the overall project and helped migrating from Objective-C to Swift 4.x
Working in an English speaking environment I supported with test-driven implementation of new product functions using Swift / Objective-C and MVVM, MVP in biweekly sprints for the ImmobilienScout24 App. I also consulted in evaluation of new product ideas, feasibility study to connect external service providers.
Support in maintaining an iOS app for a leading German multinational automotive company. Implemented new features in weekly sprints, performed code reviews and refactored several parts of the app to reduce technical debt. I also implemented an app (from scratch) for visitors of congresses to manage their favorite lectures, asking questions to the referents and reviewing the whole event agenda. The app uses Google Firebase as backend, the main architecture is built upon MVVM and set its focus upon offline capabilities to deal with bad network coverage.
Technical lead and manager of various projects for well-known, multinational clients (e.g. Daimler AG, Mercedes-Benz Museum, Autostadt / Porsche AG). I implemented iOS apps as lead developer as part of a team with varying sizes like the Daimler AG Entertainment app, the Daimler AG Jobs app, an app for the Porsche AG for the new opened Porsche pavilion at the Autostadt Wolfsburg. Besides, I lead the development team and optimized the processes and procedures of the development stack.
We implemented rich internet applications (RIA) with Flash, Flex and web applications for various national clients. Main focus was developing customized content management systems and individual web apps.
I worked as idea engineer for the Zephram GbR, moderated workshops and developed product ideas.
Implemented rich internet applications (RIA) with Flash, Flex and Silverlight and web applications for various larger clients. Created a prototype of a possible online video analyzing and editing tool with Silverlight for a presentation at the Cebit 2012 together with Microsoft.
Objective-C, Swift, Flutter, Redux, Cocoapods, Carthage, Xcode, Dart, JSON, Fastlane, Dependency Injection, MVVM, MVP, MVC, Broadcasting Pattern, VIPER, Unit Testing, XCTest, Core Data, Native Apps, Salesforce SDK, Couchbase lite, PromiseKit, Tesseract OCR, Git, Browserstack
TDD, Rapid Application Development, Scrum, Clean Code, Continuous Integration, Continuous Delivery, GitHub, Gitlab, Project lead, Agile Development, Jira, Confluence
REST, AWS, Serverless, MySQL, Kubernetes, Prometheus
Professional working proficiency
08/2005 - 05/2011
Thesis: Acceleration of computerized decision making processes with pairwise comparisons based on sorting algorithms.