A technical concept describes the technical procedure that is to be used to implement a business concept. Depending on the level of detail, it describes quite precisely which aspects of the business concept are to be solved with which technical implementation. Various principles are followed in the process.

Developers should plan the implementation of a requirement in detail before they start. In this phase, it is important to ensure that all aspects of the business concept are taken into account. This allows any concept gaps to be found early on, which should be closed before implementation. The detailed plan also enables a detailed and well-founded estimate of the effort required to realize the requirement. As a quality assurance measure, the concepts thus play an essential role at an early stage of development and prevent costly adjustments later on.

Ideally, all developers at Mercoline should create technical concepts for the requirements that they implement themselves. The created concept is then reviewed by colleagues experienced in the respective solution. The goal is not to check whether every fork in the source code has been thought out in advance. Rather, the focus is on the following questions:

• Is the concept comprehensible and coherent?
• Have all aspects of the technical concept been considered?
• Have new interfaces/interfaces to be adapted been properly thought through?
• Does the solution fit into the target architecture of the application?
• Are there any open points that require further business or technical input for clarification?

A technology concept ready for implementation was thus always reviewed and jointly agreed at least in a four-eye process.

Even if the concept is prepared for implementation for someone else, it can make it much easier to get started with a topic. The overview of the components involved as well as the type and scope of the changes helps colleagues who have not yet had any contact with a solution to find their way around. Discussing technology concepts together is therefore also an integral part of onboarding.

The core of the technology concept is the elaboration of the content based on central aspects of the development or the development objects to be changed and created. These must be considered to varying degrees depending on the topic. It is important to proceed according to a kind of checklist: for each requirement, all possibly relevant aspects must be examined again. The checklist gives a detailed impression of the points in the application and the development objects where changes need to be made or new objects created. Even if no special treatment of a sub-item is required in a specific case, the documentation that nothing needs to be done is worth more than no indication of this - it becomes clear to anyone reading the concept that some thought has been given to the item. The message here is: explicit statements leave less room for (mis)interpretation. Furthermore, the elaboration should always be transparent: at points with uncertainties, the concept can go very deep; components that still need to be clarified/open must be clearly stated so that they can be discussed in the review process.