Crystal Clear (software development)

Crystal Light is a family of software development methods, which is expected to Agile methods of software development. The members of this family are typically referred to with colors. The simplest way of contrast, called Crystal Clear (, clear ').

Crystal principles

The Crystal variants

Crystal is not a single method, but - as mentioned - a family of methods with variants.

This division has the sense that on the one hand a matching to the project circumstances rule set can be selected, on the other hand, those rules must not be individually negotiated and agreed.

Division into variants

The choice of the Crystal variant depends on the number of people involved and the criticality ( degree of risk ).

The methods are named with colors: Crystal Clear, Crystal Yellow, Crystal Orange, Crystal Orange Web, Crystal Red, Crystal Magenta, Crystal Blue. The color mainly reflects the number of people. Thus, the simplest way of Crystal Clear is recommended for team of two to six people.

Criticality, however, reflects the risk, ie what type and extent of damage in case of failure of the project is to be expected. Depending on the criticality of a " hardening " of the respective crystal variant is selected. As levels of criticality are defined in Crystal: Threat of customer satisfaction, loss of money, loss of image, and as the highest level: the loss of human life.

Depending on the Crystal variant, change the number of roles, the amount of methods to be used and the extent of documentation.

The classification according to criticality and number of employees is done according to the following scheme:

Selection of variant

Mean danger for

Grouping by number of employees is based on the fact that the communication overhead with increasing number of employees must be structured differently. While a team of six people can still drum up any time informally (spatial proximity is indeed given by the principles ), you have to make a date with a team of 20 people already. In contrast, 60 people a common discussion is unrealistic.

For each of the group sizes, different communication systems and technologies are proposed.

Grouping by criticality, however, affects it, the procedure is as formal and precise. The more serious the risks, the more overhead is taken for the correctness and security of the program into account. Again, there is a staggering of the methods to be used.

The combination of the two criteria is the short name of the specific variant can be found, the details of which can then be directly unique look. This adaptation to the project circumstances is given without negotiating one would long which rules should come because in this case the application.

Comparison with other agile methods

In relation to other Agile methods (such as Extreme Programming ) Crystal is considered by its proponents as a less dogmatic and formalized. So at Crystal Clear will never pair programming or customer on site (, customer site ' means a representation in the development team ) are required.

Plain, one can say that Extreme Programming revolves around the way of working, whereas Crystal is based on the individual project.

Crystal performs non-permanent methods for the team, but is determined for each individual project for the new methods to be used. For simple projects, this can cause many of agile methods used in XP are used; For more complex projects, a variant would be used, which is more like complicated process models.