Possible targets, to be discussed, include:

• replacement of data structures:
  • old ROOT 3- and 4-vectors with new ones (possibly non-breaking change)
  • replacement of complex data structures with simple ones (std::array if supported by ROOT at the time we need it, std::vector, replacing std::set and std::map)
• definition of a data augmentation protocol (e.g. with parallel collections)
  • development of viewing tools to push the structure behind the interface
• reorganisation of data structures; candidates:
  • recob::Cluster: very heavy-weight, could be split by augmentation
  • recob::Track: needs redefinition
  • recob::Shower: it's a stub