Trajectory storage has always proved problematic for the molecular simulation community, as large volumes of data can be generated quickly. Traditional trajectory formats suffer from poor portability, large file sizes and limited ability to include metadata relevant to simulation. The Trajectory New Generation format developed by the GROMACS team represents the first trajectory format with small file sizes, metadata storage, archive integrity verification and user/software signatures. The refactoring of this code into C++ will provide clarity and usability for both the GROMACS project and for other simulation packages and analysis tools and is the primary goal of this project. Thin FORTRAN and Python layers are also desirable to encourage widespread adoption and are a secondary goal of the project. An efficient and transferable implementation of the TNG format will represent a major step forward for the computational molecular sciences community, enabling easy storage and replication of simulations.