PayEx

Johan was the architect and senior developer for a series of Java micro services, for a financial system. Major technologies used were Spring Framework, Oracle databases, Rest communication and ElasticSearch caches. The system handled value codes, i.e. discounts for certain products, given to certain customers. The system handled using such codes, as well as issuing new ones. This was business-critical software, where customers would stand in a store and scan their value codes, so the system had to be very responsive with minimal latency. When Johan was brought into the project, he made several performance-boosting improvements to the design, such as adding multi-layer caches and buffers. Johan took the initiative and responsibility of bringing in application monitoring to the system. He was the lead developer of the customer facing parts of the system.

Johan also worked on several other core financial systems during his time at PayEx. He held multiple sessions for his team on testing, test-driven development and code quality, and he held coding dojos. He introduced technologies such as application monitoring and non-intrusive exposure of metrics and meta-data. Johan took the initiative to make everyone focus less on silo-programming and individualism and more on being an effective team together. He received much acclaim for professionalism, technical experience, his will to share knowledge and help the whole team improve, as well as for socializing and quickly becoming a natural part of the team.

The PayEx logo and a webshop integration for an example project: