Anything even remotely new is usually not a candidate for these types of long duration missions. Part of it is institutional inertia, but also partly a desire to use a technology stack that will still be in use decades from now. Even for missions that only take a few years, some of the same people will work on those missions as well as decade plus missions, so you have to hire people who are experts in mature technologies. Institutions like NASA and ESA want to work with a technology stack that will remain stable and which they know will be maintainable by people in the future.
C and languages that compile to C (Fortran is used as well) are often employed since you have powerful control over memory usage.
Source: I work in the aviation industry, where the technologies are different but the lifecycle concerns are very similar.
C and languages that compile to C (Fortran is used as well) are often employed since you have powerful control over memory usage.
Source: I work in the aviation industry, where the technologies are different but the lifecycle concerns are very similar.