ETL programmer C# (time & material) - please read document

Our team implements POS-solutions (cash register solutions) for the retail business.
Our typical clients operate an enterprise architecture which comprises ERP-systems and various other systems.
Our POS-Solution requires data from the customer’s systems.
Our POS solution also provides data to the client’s systems.

We seek freelancers who are competent and willing to team with us in customer projects.
The freelancer(s) must have a proven track record in the following skills and experience
 Programming in C# in Visual Studio
 Reading and understanding of XSD and complex XML
 Data modelling
 Programming of extraction mechanisms/logic
 Programming REST-clients and -REST-Services
 Programing transformation logic/ mechanisms from complex XML into other data models, data formats and file formats - and vice versa
 Good English language skills

Nice to have:
 Experience with various database technologies
 Programming of database connectors
 Various SQL