These are selected projects for references.





Books

Objective-C
This book is in German, it teaches Objective-C at the beginner level by walking through examples.
The description page is in German.

Swift
This book is in German, just like the book on Objective-C it teaches Swift at the beginner level by walking through examples.
The description page is in German.
What Others Say
“ What I particularly appreciated was the professional approach and work discipline during implementation. This made working with Wolfram very pleasant. I am very happy to recommend him. ”
“ I particularly liked Wolfram's flexibility and perseverance in challenging situations. For me, customer feedback is paramount, and after Wolfram's training, customers were always satisfied and gave good feedback. I am always happy to recommend him. ”
“ I especially liked the documentation at the end which made it transparent what was implemented and how exactly the interface works. ”
Work on Home Connect
- My role
- As a Senior Software Engineer I have had the opportunity to be a part of the team early on (since 2012). I have been actively working on this project until July 2021.
- What I have contributed
- I have devised the architecture and subsequently developed the communication library written in C++ which is used both in the Android and iOS apps. I have also written parts of the UI of the iOS app, initially in Objective-C and later on in Swift. I have written the architecture documentation and also contributed various support libraries and scripts in Python and bash. These were used to operate and maintain the CI/CD infrastructure for a variety of platforms.
This project was exciting for several reasons. It has taught me the importance of DevOps, continuous integration and continuous deployment, the intricacies of complex software architecture, and the collaboration of large inter-departmental teams towards an app that works with a huge variety of appliances.
I have talked about technical lessons in a Presentation at the Developer Week 2016 conference. - This project is an ongoing collaboration with UXMA (formerly ma design).
Set Up CI/CD Pipeline For UI framework
- My role and contribution
- As an external consultant I have set up the CI infrastructure for both the iOS and Android build chains on Microsoft Azure, written UI and unit test cases and documentation for stake holders in English. On iOS the framework is written in Swift and on Android it is written in Java.
Set Up CI/CD Build For XCFramework
- My role and contribution
- As an external consultant I have revised the build process locally and then adapted and amended the CI/CD toolchain to build both the framework and integration within the app. During this process I identified and improved further automations in the existing toolchains.
Co-found tamanguu
- My role
- As co-founder and CTO I have devised and set up the web presence, the cloud infrastructure on Microsoft Azure and the architecture of the web app. Together with my co-founder we were running the company and managing the people within the organization.
- What I have contributed
- We were a team of six people (full-time and part-time) with five more freelancers and students working for us part-time. Our app uses Clojurescript based on re-frame which in turn is based on Facebook's React. The backend runs a Clojure application on Java 8 that stores data in a PostgreSQL database and serves content via a REST API and a websockets API using nginx. A set of Python scripts is used for maintenance and supporting tasks.
While working in the startup I have learned a lot about Oauth workflows, the Google contacts API, the Microsoft graph API, CalDAV and vCards, the Nylas API, the payment APIs of PayOne, Stripe and Chargebee, GDPR compliance, in-app analytics with Segment.io, Google Tag Manager, Google Analytics and Heapanalytics, and building an architecture that scales to hundreds of users. It was also very insightful to do the user interviews and understanding how investors view startups with concepts like the Marmer stages and its notion of consistency. I got to learn a bit of everything which made this experience unique. - What happened then
- The app went through several iterations. While we mastered the technological challenges, we didn't do as well on the business side. We had a few users who liked the product, but they did not like it because of our unique feature (guide recommendations for networking). At the end of the day we had come to realize that we were not solving the most pressing and urgent problem of our audience. That's why we failed to build a successful business and why I had decided to exit.
Consult Calistix Team
- My role
- As an external consultant I have worked with the team and in particular the developers in 2012.
- What I have contributed
- I have devised the architecture of the initial version in Objective-C.
I have also helped with debugging and recommended best practices for future developments. This was a smaller project; still I have learned how the team did some very thorough usability testing and how they invested heavily in outstanding content – the exercises and their descriptions with two distinct trainers, male and female.
Develop iPad App iTECPad
- My role and contribution
- I have helped train the developers in Objective-C and devised the architecture of the initial version written in Objective-C in 2011. The app also featured the PowerPlot library that I have developed.
The app is no longer available on the Apple app store, but it is still used internally by TEC Microsystems. - This project was a collaboration with global prognostics GmbH, Berlin.
Develop iPad App LSP 500 Pro
The LSP 500 Pro is a professional speaker developed by Sennheiser which can be remote-controlled by an app for the iPad.
- My role and contribution
- As a Technical Project lead I have made the fundamental architecture decisions and led a team of four developers during the development of the app in Objective-C. I have been working on this project in 2012 and 2013.
- This project was a collaboration with UXMA (formerly ma design).
Develop iOS Charting Framework PowerPlot
- My role and contribution
- I have developed the API and the full implementation in Objective-C and it was a commercial project for some time. I have received a few contributions from outside collaborators. As a commercial project I sold a few licenses, but overall I decided not to pursue it further as a business. I have now made the library Open Source.
Teach Students at EMS Internship
- My role and contribution
- I have mentored groups of students for several years on several projects. The one thing I noticed consistently was that the major challenges were not of technological nature, but rather in how requirements, progress and results is communicated to stakeholders. The good news is those issues are resolved with the right systems and working habits, which are much easier to acquire than technical skills. It is for this reason that I focus so strongly on the development of crucial soft-skills, foremost collaborative group work and presentation abilities in my Teaching Statement.
- This project was a collaboration with UXMA (formerly ma design).
Develop iPad App (Enterprise/In-House)
- My role and contribution
- As the main developer I have designed and implemented an iPad-App for in-house use in a daughter company owned by an energy management enterprise listed in the DAX. The app used the platform's capabilities (which were quite new back then) like GPS, photos, airprint, asymmetric RSA encryption and multiple synchronization methods with the backend. It needed to replicate parts of the Enterprise database locally using Core Data. I worked on this project in 2011.
Author field-theory.org Blog
- Technologies used
- I have migrated technologies a few times over the years. Initially, it was hand-coded HTML, then I set up my own templating system based on m4. Next I migrated to the Python-based Genshi toolkit before settling on hugo.
Before the start of the project, we had to prepare a comprehensive quantitative analysis of the performance of thermoelectric elements prior to meeting with a customer. This was time-consuming, inaccurate and (numerically) unstable, and important analysis aspects were also missing. Subsequently, we had to use manual work-arounds to transfer the results obtained from a legacy solution running on Windows into a form that could be presented to the customer.
The project’s goal was the development of a solution running on iOS with Wolfram's support. A key feature of the app was the interactive visualization, which was done by Wolfram using a graphics library he developed himself. This allowed us to show our customers the quantitative results not only visually, but even live and interactively. Thus, time-consuming manual work-arounds and long preparation times for individual customer meetings were eliminated.
What I particularly appreciated was the professional approach and work discipline during implementation. This made working with Wolfram very pleasant. I am very happy to recommend him.
Die Lage vor Projektbeginn war, dass wir vor einem Kundengespräch eine umfassende quantitative Analyse der Performance thermoelektrischer Elemente erstellen mussten. Diese war zeitaufwendig, ungenau und (numerisch) instabil, es fehlten zudem wichtige Analyse-Aspekte. Anschliessend konnten wir die gewonnenen Ergebnisse nur über manuelle Umwege aus einer Legacy-Lösung unter Windows in eine für den Kunden repräsentable Form überführen.
Das Projektziel war, mit Wolframs Unterstützung eine Lösung als iOS App neu zu entwickeln. Ein Key-Feature der App bestand in der interaktiven Visualisierung, die von Wolfram mit einer von ihm selbst entwickelten Grafikbibliothek vorgenommen wurden. Dadurch konnten wir unseren Kunden die quantitativen Ergebnisse nicht nur visuell, sondern sogar live und interaktiv vorführen. Die aufwendigen manuellen Umwege und langen Vorbereitungszeiten für einzelne Kundengespräche sind dadurch entfallen.
Was mir besonders gefallen hat, waren die professionelle Herangehensweise und Arbeitsdisziplin bei der Umsetzung. Dadurch war die Zusammenarbeit mit Wolfram sehr angenehm. Ich empfehle ihn sehr gerne weiter.
We develop automations for our customers, which are triggered using voice commands. This is essential for customers suffering from tendonitis. They use Dragon not only to dictate text but also to replace the mouse. Due to short notice cancelations we also needed trainers, especially English-speaking instructors.
Dr. Wolfram Schroers helped us evaluate and customize solutions for Dragon on the Mac. For an exceptionally difficult problem involving an emulator, he succeeded with a solution where the manufacturer and other vendors had failed. In addition, as a bilingual trainer, he stepped in flexibly and on short notice to hold English-language training sessions.
I particularly liked his flexibility and perseverance in challenging situations. For me, Customer satisfaction is vital, and after his training, customers were always pleased and gave positive feedback. I am always happy to recommend Dr. Wolfram Schroers.
Wir entwickeln für unsere Kunden Automatisierungen, die diese mit Sprachbefehlen starten. Dies ist wichtig für Kunden, die unter Sehnenscheidenentzündungen leiden und Dragon nicht nur nutzen, um Text zu diktieren, sondern auch um die Maus zu ersetzen. Durch kurzfristige Ausfälle bei Schulungen brauchten wir kurzfristig verfügbare Trainer, insbesondere wenn es um englischsprachige Angebote ging.
Dr. Wolfram Schroers hat für uns Lösungen für Dragon auf dem Mac evaluiert und angepasst. Für das schwierige Zusammenspiel mit einem Emulator hat er auch dort eine Lösung gefunden, wo der Hersteller und andere Anbieter nicht mehr weiterwussten. Zudem konnte er als zweisprachiger Trainer kurzfristig und flexibel einspringen, um englischsprachige Schulungen zu halten.
Mir hat insbesondere seine Flexibilität und sein Durchhaltevermögen in herausfordernden Situationen gefallen. Für mich ist vor allem Kundenzufriedenheit wichtig, und nach seinem Training waren die Kunden immer zufrieden und haben eine positive Rückmeldung gegeben. Ich empfehle Dr. Wolfram Schroers immer gerne weiter.
We had been facing a technical problem with a hardware developed by our customer, for which we implemented a framework with an API. We did not have the necessary knowledge of our customer's components in-house. We needed an expert in the field to handle the task quickly and reliably.
Wolfram analyzed the problem and found the issue in the communication protocol. In situations like this one, I have often witnessed Wolfram document the situation effectively (e.g. by recording videos), and highlight the actual behavior and the desired result. That’s what he did in this case. This allowed the developers on the customer side to understand exactly what he found, use that knowledge to identify the problem, and then quickly solve it.
I especially liked the documentation at the end which made it transparent what was implemented and how exactly the interface works.
Can I recommend Wolfram? Yes, absolutely, I cannot say more! We are looking forward to commission him again.
Wir hatten ein technisches Problem im Zusammenspiel mit einer Hardware, die von unserem Kunden entwickelt wurde, und für die wir ein Framework mit einer API implementiert haben. Das notwendige Wissen über die Komponenten unseres Kunden hatten wir nicht in-house. Wir brauchten einen Experten auf dem Gebiet, der die Aufgabe schnell und zuverlässig abarbeitet.
Wolfram hat das Problem analysiert und fand, wo die Schwierigkeit im Kommunikationsprotokoll liegt. In solchen Situationen habe ich Wolfram schon oft dabei erlebt, wie er klare Dokumentationen erstellt (z.B. indem er Videos aufnimmt), die das tatsächliche Verhalten und das gewünschte Ergebnis präzise aufzeigen. So auch hier. Dadurch konnten die Entwickler auf Kundenseite genau sehen, was er gefunden hat, mit diesem Verständnis das Problem identifizieren und anschliessend schnell lösen.
Besonders gefallen hat mir die Dokumentation am Ende, so dass nachvollziehbar ist, was umgesetzt wurde und wie genau die Schnittstelle funktioniert.
Kann ich Wolfram weiterempfehlen? Ja, absolut, da kann ich nicht mehr sagen! Bei Bedarf kommen wir jederzeit sehr gerne auf ihn zurück.
Selected Scientific Publications
- Nucleon Generalized Parton Distributions from Full Lattice QCD
- Ph. Hägler, W. Schroers et al., published in Phys.Rev.D 77 (2008) 094502, more than 300 citations by May 2020.
- Nucleon structure from mixed action calculations using 2+1 flavors of asqtad sea and domain wall valence fermions.
- LHPC collaboration, published in Phys.Rev.D 82 (2010) 094502, 240 citations by May 2020.
- Light hadron spectroscopy using domain wall valence quarks on an Asqtad sea
- A. Walker-Loud et al., published in Phys.Rev.D 79 (2009) 054502, more than 190 citations by May 2020.
- The Nucleon axial charge in full lattice QCD
- LHPC collaboration, published in Phys.Rev.Lett. 96 (2006) 052001, more than 160 citations by May 2020.
- The N to Delta electromagnetic transition form-factors from lattice QCD
- By C. Alexandrou et al., published in Phys.Rev.Lett. 94 (2005) 021601, more than 100 citations by May 2020.
- Transverse structure of nucleon parton distributions from lattice QCD
- LHPC and SESAM Collaborations, published in Phys.Rev.Lett. 93 (2004) 112001, 80 citations by May 2020.
- Generalized parton distributions from lattice QCD
- QCDSF Collaboration, published in Phys.Rev.Lett. 92 (2004) 042002, 180 citations by May 2020.
- Advanced algorithms for the simulation of gauge theories with dynamical fermionic degrees of freedom.
- Dr. rer. nat. Thesis, Fachbereich Physik, Bergische Universität Gesamthochschule Wuppertal, D-42097 Wuppertal, Germany. November 2001. In English.
PDF-file from the local server. - Numerische Untersuchung der selbstkonsistenten Sphaleron-Konfiguration der elektroschwachen Theorie.
(“Numerical investigation of the self-consistent sphaleron configuration in the electroweak theory.”) - Diploma Thesis, Institute for Theoretical Physics II, Ruhr-Universität Bochum, D-44780 Bochum, Germany. November 1996. In German.
PDF-file from the local server.