Berlin/remote Lead Software Developer/Architect, Industrial IoT Cloud/onPrem Solutions, C#/.NET/Java

Industrial IoT with Azure for global company in Industrial IoT services
Key technologies: .NET, Java, Spring Boot, Azure IoT Edge, Azure Industrial IoT, OPC UA, Microservices, Kubernetes, GraphQL, Azure Functions, Azure Data Explorer (Kusto, Time Series DB), Azure Event Grid, Azure EventHub, Azure IoT Hub, Azure IoT Edge, Azure Service Bus, Large Scale Data Storage, Service Bus, Mongo DB, Azure CosmosDB, SQL Server, Terraform, ArgoCD, ATTD/Cucumber

symmedia has been developing service solutions for mechanical engineering since 1997. The symmedia SP/1 software is used as the "Internet of machines" in over 100 countries. Leading machine manufacturers and operators use symmedia SP/1 as a convenient service portal: Remote Service, Parts, Maintenance and Monitoring are proactively offered directly at the machine. 

The existing, server/client based product SP/1 offers a remote access, service, and management solution for industrial machine manufacturers worldwide and is being replaced by a green-field developed cloud-based solution. The new product will be used by manufacturers, service providers, and customers to remote service machines, collect data, calculate KPIs, analyze machine behaviour, and provide a global data analysis and processing platform for 3rd party vendors. The scale of the project at project start alone includes several thousand IoT edge devices within connected factories, and gigabytes of data collected per machine for predictive maintenance and quality prediction of the products manufactured. Data collection in the first phase is performed through OPC UA, but Symmedia’s product support includes dozens of custom industry protocols.
The system is built in a way so that Symmedia can offer generic IoT platform capabilities to manufacturers and clients, with a “marketplace” offering 3rd party data acquisition and processing apps, that are then deployed in a safe and shielded environment on the IoT edge devices.

The project: As a cloud solutions architect, together with experts from the client and their parent company, I was responsible to consult and largely design the cloud and IoT edge infrastructure and technical details of most backend services. Besides consulting on the general parts, my focus was on data collection and processing beginning at the factories and IoT edge devices, over hot/cold data path, processing and storing the data in Azure Data Explorer and CosmosDB, and providing GraphQL services that were linked together with GraphQL federation.
I designed and developed the Azure Industrial IoT edge solution starting from the application marketplace, deployment of the solution to IoT edge devices, monitoring, and reporting. This also included the actual application to acquire data via OPC UA from machines and transmit, store, and process it in the cloud. We furthermore analyzed the usage of different industrial protocols, including the emerging umati / OPC UA Machinery specification, and had meetings with VDMA and Microsoft to be able to potentially include this in the Microsoft Industrial IoT solution.
During this project we worked together with the Azure IoT Edge and Industrial Azure IoT Edge teams from Microsoft to fix issues and add much required functionality. I furthermore handled the public bug reporting and generic community interaction  with Microsoft, Terraform, etc.; a long list of GitHub bug reports in Microsoft’s IoT, Industrial IoT, and Azure Java SDK projects gives an overview of this. 
I furthermore introduced concepts like acceptance test driven design using Cucumber, and consulted in integration tests and CI/CD pipelines for end to end testing beginning at the data collection towards the data processing and querying stage. I was member of the core QA team.
The project uses Azure Data Explorer (Kusto) as data storage, and various techniques such as CosmosDB and EventHub for hot path data transmission.
The CI/CD pipelines are hosted on Azure DevOps, extensive integration test suites run on pull request completions, and deployments to test devices start running.
The infrastructure is hosted in Kubernetes and managed with ArgoCD and Terraform.
Most Microservices, Azure Functions, and IoT Edge modules are written in Java (11/17), with some written in .NET Core for specific reasons, or because the mother company GFMS is using .NET exclusively. My hybrid Java/.NET knowledge was an advantage in this project, with my Java knowledge being reactivated at the beginning of the project.

Key technologies : .NET, Microservices, Azure App Service, Azure Functions, Azure FrontDoor, Azure
EventGrid, Azure EventHub, Azure Service Bus, ASP.Net Core, Queues, Data Storage, Service Bus,
mongoDB, Docker Containers

Mister Spex is the largest online optician in Germany and Europe. With headquarters in Berlin, Mister
Spex is one of the pioneers in the online marketing industry for optical products due to their
multichannel sales concept. The company not only sells online, but also has many "offline-stores"
across Germany.

Having grown fast recently, Mister Spex needed a way to centrally organize and manage available and
reserved stock, calculate delivery times, and reply to queries of product availabilities. Mister Spex also
needed a generic template for microservices and a platform and "rule book" of how to connect
existing and future services

The project : Development of a stock and reservation tracking system as a .NET Core 3.1 microservice,
running in Azure. I used MongoDB as backing database because of the document-based architecture,
and the transaction support (only limited support for this in Azure CosmosDB). Test-Driven-




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Development with ATDD and SpecFLOW, full CI/CD pipeline with unit and functional testing, full API
specification test coverage. Auto-scaling, automatic nightly benchmarks and performance analysis.

Setup and integration of monitoring. Schooling of on-site developers in .NET Core, the technologies
used, and principles of ATDD. Help with integration in the existing technology landscape.

Analysis of current communication systems and consulting in creating a new event based architecture.
Based on EventGrid and Service Bus, to easily integrate with current and future infrastructures.
Defining the interfaces and event types for the first system to use it.

Key technologies : .NET, Azure Functions, Azure Microservices, ASP.Net Core, Signal-R, WebSockets,
Azure App Service, Queues, Data Storage, Service Bus, HTML, JavaScript, Azure CosmosDB, Rabbit MQ,
mongoDB, Docker Containers

Aveator is a leading business caterer with multiple locations including sales, support, manufacturing
and delivery in Germany. Sales is done either directly by the customers via a web shop and/or through a
hotline with professional support that can create custom orders and advise customers on orders. The
whole company is computerized, including screens at the production facilities, orders sent to the
drivers, and customer feedback. A failure of the ICT system will jeoparidize production, delivery or
handling of sensitive upscale food with a subsequent disruption of clients' business meeting and big
receptions. High availability while maintaining flexibility and a continuous rollout of changes is key.

The project : Aveato was in the final stages of migrating their existing platform into the cloud
(Microsoft Azure) and a refactoring into microservices for more flexibility. I helped with expert
knowledge and additional manpower to keep a crucial deadline, transferred knowledge about cloud
platforms and provided improvements to the SCRUM process. My work consisted mainly in work on
the backend (.NET core, Rabbit MQ, mongoDB, Azure, Docker, Elastic Search, ...) and few GUI changes
(HTML / Angular), besides to providing consulting and assistance for key elements.




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Low latency video streaming via Cloud providers, Video data processing

Key technologies : .NET, Azure, Amazon Web Services (Video), JavaScript, Websockets, RTMP, SRT,
MPEG2 TS, WebRTC, Azure App Service, Queues, Data Storage , Service Bus, Payment systems

For a startup that is still in black-ops mode and I can't name by NDA obligation.

The project : The service involves low latency video streaming, processing, storage, video
teleconferencing and payment systems on frontend and backend.

Key technologies : .NET, WebApi, SQL Server, HTML5/CSS, JavaScript, Azure App Service, Azure Queues,
Azure Data Storage (tables, etc), Azure Service Bus

IconMobile develops mobile application for global key players such as Procter & Gamble. P&G owns
brands such as Oral-B electric toothbrushes. The latest generations are able to connect via Bluetooth to
a mobile phone, display zones where brushing needs to be improved, and enables syncing and
analyzing data in the cloud for a better experience and expert brushing advice.

The project : IconMobile had developed the mobile application and had issues with the backend
external developers have been working on. I was hired as a .NET expert to find the increasing
performance issues and migrate the old application to a newer base. The project was completely
rewritten and in close coordination with the mobile app team I took over also the TPM role for the
backend.

The contract and project scope extended from initial 3 months to about 1.5 years and extensive
reworks under my control due to high customer satisfaction.

The scope was extended to make the application unit-testable (rewrite and modularization of terribly
intertwined "spaghetti" code in the API controllers), making the application scalable (implementation
was limited to few concurrent, mutually blocking threads, without any database indices or a finished
data access layer), implementing new features and preventing the backend from running unmonitored
and uncontrolled, and adding data analysis (brushing analytics) to aid customers. (Data processing and
data set correlation).

In later stages I was responsible for getting the backend and P&G's datacenter regarding our data fully
GDPR compliant (EU General Data Protection Regulation, DSGVO Datenschutzgrundverordnung),
migrating the base of the aged backend to a newer platform and architecture, and migrating the app to
Azure App Service, Azure Queues, Azure Data Storage (tables, etc.), Azure Service Bus.

I also fully documented all parts and aspects of the app, the requirements, the workings, data
analytics, etc.

Key problems: Besides the high user count and the old base technology, the key problem was the
structure of many scattered service providers to Procter & Gamble. During the project, managers,
companies responsible for services, and specifications changed often on a weekly basis, and it was
hard to find an authoritative source of information. IconMobile, and specifically my co-workers and I,
then took responsibility to document the customer's wishes, and to work hard to overcome such
problems. I often took on a diplomatic and neutral role as external entity, to reduce friction between
those parties.




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Migration to Azure was plagued by the previous IT service provider's level of commitment but was
ultimately successful due to the great effort and excellent perseverance on the side of IconMobile's
team.

Technologically the backend had to face the typical issues like unreliable remote backends, mobile
applications that behave badly (accidental DoS by faulty mobile apps), big piles of old data that needed
to be reduced to simpler data sets, and the fact that most users using the app tend to all use it at the
same times: In the morning, and in the evening, just before going out of the house and before going to
bed. All classical issues that were handled with help of Azure.

09 / 2016 - Complete web framework replacement (ASP 1.1 to MVC, EF 6 and Angular 2)
02 / 2017 Bundesdruckerei (German federal printing office) - Leading developer

Key technologies : HTML5/LESS, client side JavaScript/TypeScript, Angular 2, MVC on IIS, single page
application architecture, client side caching, Entity Framework 6, introduction to new technologies to
existing employees.

The Bundesdruckerei ("Federal Printing Office") is a German manufacturer for banknotes, stamps,
identity cards, passports, visas, driving licences, vehicle registration certificates, generic access control
systems for high security areas, trust center applications and an electronic certificate publisher. Once a
federal entity, it has since been privatized but is now again government owned. The services and
products offered are not only provided for the German but many foreign governments. Highest security
standards and procedures are in place, given the sensitivity of the data processed and stored and the
real-life and political value of the physically produced items. High security and high availability are thus
key requirements.

The project : The Bundesdruckerei had been using web applications for the management of all
processes regarding the whole lifecycle of their products such as ordering and order management of
devices or ID cards, activation of ID card readers, revoking of lost certificates or ID cards, customer self
service, rights management and provisioning, and service ticket management since 2003. In 2016 it
was decided that the old and dated technology (ASP.NET 1.1, JavaScript as Backend language, direct
SQL statements or obscure wrappers, large monolithic chunks of logic, no modularization, lack of any
modern HTML, CSS, lack of JavaScript frameworks and data binding) became hard to manage,
impossible to unit-test or automate and had to be updated.

The initial scope was to replace one module and decide afterwards which direction to go, but this was
extended to creation of a whole new framework, replacement of the security and rights management
and provisioning system, a central OAuth2 single sign on system, a UI redesign and training of the
existing internal employees on the new technologies.

Key problems: Besides the high security requirements, the key problem was the largely dated old
technology, lack of development procedures, business analysts, or any form of documentation. Test
databases or existing unit tests were virtually lacking. The customer's decision to switch from the
proposed Knockout client side data binding to the more complex Angular 2 framework increased the
scope further. Lacking a business side or a development process with goals and deliverables required
me to introduce a mini-version of SCRUM into the project to be able to provide direction.

My role: As the initially single developer on the project my role was to look at the existing situation,
analyze which future proof modern frameworks can be used, and to document the existing
functionality by using either actual unit tests, or acceptance tests. I documented the module that had
initially to be replaced with Gherkin-style acceptance tests (feature files) and got the client to sign off
on that specification. Because of the complete lack of development process I started a mini-version of
SCRUM using a local instance of Jira. After a short while I was able to show a working proof of concept




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of how modern modularization, data access with Entity Framework, Unit Test and Acceptance Tests,
JavaScript/TypeScript and TypeScript unit tests, security frameworks, IoC / dependency injection, and
other modern technologies look like.

The client was impressed and tasked me together with another contractor, with creation of a whole
new framework, a switch to Angular 2, integration of the frameworks into the local infrastructure,
tutoring of the employees in the new technologies, and a replacement of the security management
and provisioning pages.

Key technologies : HTML5/LESS, massive client side JavaScript and MVC, single page application
architecture, client side caching, document-storage like database, JavaScript calculations and unit
testing, in-browser HTML5 editors and server-side PDF generation.

Rabobank is a Dutch multinational banking and financial services company headquartered in Utrecht,
the Netherlands. It is a global leader in food and agricultural financing and sustainability-oriented
banking. The group comprises local Dutch banks under a central organization, and a large number of
specialized international offices and subsidiaries. Rabobank is the second-largest bank in the
Netherlands in terms of total assets.

The application : "LQA v3" is a greenfield ASP.NET MVC 5 web based application used to track loan
quality assessments, replacing an older version, which suffered from very bad user perceived
performance and high fragility. A loan quality assessment is the process by which a bank plans
strategies for customers being endangered of going into default (fail to pay their loans), or are already
in an ongoing default. Plans are draft up, calculations are made, and strategies are presented to
various decision boards around the globe. Banks want to prevent client bankruptcy as much as
possible, rather writing off debts or restructuring loans instead of a full-loss, and thus well planned
strategies that are decided on in a timely manner are often crucial for client survival, and partial
recovery of an otherwise lost asset.

Key problems: The system is used around the clock from various worldwide locations, many of which
are located remotely with poor network connection. Efficiency in network communication regarding
AJAX calls and caching were key elements for user acceptance. The superseded version 2 of LQA used
Microsoft Word to generate reports and allowed users to add rich text and pictures to their partially
auto generated strategy reports, parsing and manipulating MS Word documents on the server. This
proved to be very fragile; LQA 3 thus rather employed structured data entry for calculations and rich
text editing in a browser based solution, with server-side PDF generation (Google Docs like editing).

My role: As lead developer of a team of 5 developers, I was in charge of the application architecture,
solving the "hard-puzzles", laying the foundation of the application, UI and UX design, tutoring my
development team in new technologies and principles, as well as actual software development. As an
agile (SCRUM) team we worked together with the business analysts, testers and product owners to
create user stories and define the scope of the application. I was responsible for interacting with other
teams whose interfaces we connected to, and the presentation of ideas and new UX mechanisms to
the product owners. Many technologies and concepts we used or developed in our team have since
then been included in the core technologies for the Finance and Risk IT department.




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Key technologies : HTML5/LESS, document-storage like database, document versioning (immutability
of entered data), reporting, multi language application

Rabobank is a Dutch multinational banking and financial services company headquartered in Utrecht,
the Netherlands. It is a global leader in food and agricultural financing and sustainability-oriented
banking. The group comprises local Dutch banks under a central organization, and a large number of
specialized international offices and subsidiaries. Rabobank is the second-largest bank in the
Netherlands in terms of total assets.

The application : "CAFE" is a greenfield ASP.NET MVC 5 web based application used to ensure that
bank employees follow EBA and Rabobank compliancy regulations and rules. All 45000 affected
employees of the Rabobank group have to enter and update confidential data into the system at
varying time periods; this data is then approved and monitored by the compliance officers, who also
use it to monitor and approve employee stock trade (preventing insider trade and various fraud
scenarios).

Key problems: Because of the confidentiality of the stored data the system falls into the banks highest
security levels. All changes must be auditable and once stored information must not be able to be
changed by the application. Compliance officers must be interactively warned if they are trying to work
on the same case, and concurrent edits must be prevented.

My role: As lead developer of a team of 2 developers, I was in charge of the application architecture,
UI design, connecting to other teams whose systems we interfaced, as well as a huge portion of actual
development. As an agile (SCRUM) team we worked together with the business analyst, tester and
product owners to create user stories and define the scope of the application. Many technologies and
concepts, such as document storage and TypeScript we used were new in the company, and I have
held talks and was tutoring my team and others in the usage. Many of those technologies have since
then been included in the core technologies for the Finance and Risk IT department.

7pressplay.com was an innovative dance video website featuring video creations of dancers,
choreographers and dance companies. Positioned as a mix of video channel, search engine and social
network, the target was to provide more exposure for commercial or independent dance and video
makers. Dance interested audience was able to search, watch, and relax on new dance videos, and
video artists were able to showcase their work and search for inspiration.

As CTO and co-founder, I was responsible for the technical architecture, most of the development and
maintenance. The site was running on ASP.NET MVC, in combination with Umbraco as Content
Management System, MongoDB and Solr for search, statistics keeping and read-only data access. We
used Linux/Lighttpd as high volume video delivery network, and a custom built framework around
Linux/.Net/Amazon EC2/S3 and FFMPEG for video upload, transcoding and streaming. Development
progressed very fast thanks to the usage of ASP.NET, TypeScript, MVC, Knockout, Bootstrap, and other
frameworks.

After the public beta and the proof-of-concept was successful, the website was closed for the public
while fundraising, promotion and video collection was undergoing for the launch. Sadly the site never
relaunched because of financing issues and personal matters, but the experience gained and the
frameworks created have been used ever since in my other projects.

113online is the web portal of the Dutch suicide prevention hotline, and very often the first place to
search for help in case of suicidal thoughts. The website is especially important in times when the
hotline is overloaded or for people seeking anonymous help.

The site is based on Drupal, with a forum system and some custom development in PHP, including
version control and project management on Git plus several ways for the staff to coordinate work and
further development. The system suffered from performance problems with high peek loads which can
happen after heavy advertisement of the site or after public events causing a raise in suicidal thoughts,
with a sudden unpredicted peek from an idle server to 100,000 visitors per hour.

The project involved heavy load testing and optimization of Drupal, searching for performance
bottlenecks, determining usage patterns of the users during normal usage and under load, and working
out caching and performance optimizations. Furthermore I assisted in the setup of the project and
source code management systems (GIT, GitoLite, etc.)

Vtality B.V. is a software house distributing out-of-the-box and custom-build web software for business
processes. Development is focused on Microsoft web technologies such as ASP.NET MVC, Knockout,
Javascript, MS SQL server and others.

I worked on the project as software developer and helped building and designing the new version of
their product base: BLOXS. The main focus was on development with MVC, Knockout, JavaScript, and
CSS design. My expertise was used during the extensive refactoring and re-architecture of the existing
codebase, I also helped the team to develop a software development process with Microsoft Team
Foundation Server. After working closely together with their main client, a big child-crèche service
company with 7000 employees, and careful assessment of the needs on the user interface and server
side, I designed (HTML/CSS) and developed front- and backend of the hour registration module,
together with an interface to the client's back office system.

NetMatch is a Microsoft technology specialist, engaging in the field of travel industry. The company
thrives to be market leader in innovation regarding new technologies, paradigms, features or customer
approaches, creating the websites, search systems and booking flows for companies like Tui, Hapag,
Tot, Corendon and Zoover. The research & development branch of "NetAssist" is located in Amsterdam
and researches innovation topics for current and future projects with special aspects of social media
integration, web technologies, cloud computing and other experimental technologies yet to come.

About the position : I worked on the innovation team, performing research & development tasks on
current or yet to be published technologies. This includes field research, prototyping, creation of proofof-concepts
and feasibility studies. The core technologies hereby used include the latest Microsoft
technologies such as .NET 4, WCF, Workflow Foundation (WF), SQL Server 2008, App Fabric, Windows
Azure Cloud services and their successors.

The most important projects include new ways for social media integration, natural language text
analysis, cloud computing and creative ways to search and find travel packages.

Hotelplan is the second biggest tour operator on the Swiss travel market with hundreds of travel
agencies throughout Switzerland and an annual turnover of 1.6 billion Swiss Francs (2010). The
Hotelplan Management AG provides company wide services and is responsible for operating the
backend and frontend computer systems, providing the operational, booking, and customer services to
travel agents, customers via web, and partners via APIs. High availability and quality assurance while
maintaining flexibility are a must not only in this company, but the whole business. The company has
subsidiaries in England and Italy.

About the position : I was responsible for the management of the "Customer and Platform Solutions"
department, overlooking the move from the existing approach of agency driven selling to a more agile
direct customer and web based marketing, as well as combining the huge number of systems into
centralized computing and service platforms for better TCO and knowledge bundling.

My team worked closely with our subsidiaries in England and Italy, and with our suppliers across
Europe, and enabled and managed pan European projects. Notable projects included the re-launches
of the booking sites of our major brands, shifting the paradigm from classical travel searching into
guided navigation and targeted marketing. My personal motto was to reduce redundancies across our
subsidiaries and brands and simplifying our IT landscape, freeing up valuable IT resources necessary for
other projects.

Besides of the department management role I acted as software architect, technology guide and
technical project advisor in many projects.

Lexware is a German financial software publisher targeting the windows desktop and is situated in
Freiburg, Germany. With a share of around 85% of the market for homes, self-employed, freelancers,
and small and middle sized businesses, Lexware can count on one million customers (2008). The
development and the release cycles at Lexware are always delicate and under high quality assurance
pressure, due to the everlasting changes in German tax law. New versions of the products always have
to be shipped at fixed dates before the end of the year. Failures in calculation and bugs in core
components thus affect a vast amount of customer's and tax statements.

About the position : As member of the software architecture team I was responsible for the evaluation,
rating, creation and architecture of the company's core components and technologies. This also
included providing to the integrated technology planning of the whole corporate group. Furthermore, I
was responsible for the introduction of certain coding paradigms improving code quality, most notably
the introduction of aspect oriented programming into our development teams (Using PostSharp with
self-coded aspects), and IoC / DI patterns.

I was also responsible for managing our external developers and partner companies in Belarus, Croatia,
and Romania, internal code reviews, "code guru and help center" for questions regarding C#, C++ and
the interoperability of those technologies, formulation of coding guidelines and the trial and appraisal
of new technologies in general.

Personally created software includes components for the inter process communication between C++,
Java and C#, extensions for an "Inversion-of-Control" microkernel based on the "Castle Microkernel"
project, various database layers and integration layers for integration of our legacy C++ components
into the new C# frameworks.

"!zip EDV-Beratung" and its subsidiary "!zip Automation" provide IT consulting, industrial automation
services and creation of specialized software by order of various big German companies, for instance
Siemens AG for which parts of WinCC and PCS7 are being developed, or big pharmaceutical or
manufacturing companies such as Bayer, for which SCADA systems are delivered.
About the position: My work at !zip was project based, with the notable core projects being:

* "!zipTest&Doc" - Quality assurance software (http://www.testanddoc.de/). Developed in C# and
.NET 1.1. The company's only "own" product.
* Porting of the WinCC data manager from C++ to C# and Managed C++ on a .NET 2.0 base. WinCC is
a SCADA / process control system from SIEMENS (http://www.wincc.de/).
* Analysis, further development and support of the process control and protocol systems for
miscellaneous installations of the "Kolbenschmidt Gleitlager GmbH" in St. Leon-Rot.
* Creation of a dedicated line network in the remote maintenance and process control system of the
public services company in Gießen (Stadtwerke Gießen) via CISCO Routers and Zyxel leased-line
modems.
* Miscellaneous other small projects and "code-guru" helping.

At the !zip company group I could help with my broad knowledge of various operating systems
including Linux, AIX and Windows, many programming languages including C/C++ and C#, and
Microsoft as well as Unix technologies.

AIK Electronics Austria was a printed circuit board plant in Klagenfurt manufacturing multi-layered
printed circuit boards for customers like Cherry (keyboards). The company consisted of three plants
situated in Klagenfurt, Great Britain and Hungary.

The company utilized a lot of Unix and VAX technologies and workstations to perform the CAD/CAM
tasks. This included utilizing a huge network of Solaris machines.

About the position : I worked for AIK Electronics' CAD/CAM and IT department during my school time
for the required internships and later voluntary as side job to gain more experience and knowledge.
My projects and tasks included programming of supportive software and system administration,
including an interconnect of the company's networks in Austria, Great Britain and Hungary with ondemand
ISDN links controlled by a router running Linux. I also helped estimating the costs and run
times of the computer guided drilling programs (CNC) by simulation and visualization of the drilling
process via a Java 1.2 based application.

My other tasks allowed me to gain huge knowledge about different Unix variants, the VAX operating
system, Linux and various programming languages.