CUBESPEC is an ESA in-orbit demonstration 6U CubeSat mission, currently in phase A/B. CUBESPEC will deliver months long series of high-resolution spectroscopy to study the structure of massive stars. The payload consists of a Cassegrain telescope with a rectangular primary mirror of 9 x 19 cm2 and a compact high-resolution echelle spectrograph. We aim at a 2023 launch demonstrating the CUBESPEC concept: providing the astronomical community with a generic solution for affordable space-based spectroscopy. The spectrograph design can be configured with minimal hardware changes for low spectral resolution (R = 50) up to high resolution (R ~ 50000) over a over wavelength ranges between 200–1000nm. CUBESPEC will use the KU Leuven ADCS for coarse pointing of the spacecraft, supplemented with a fine-guidance system using a fast steering mirror to center the source on the spectrograph slit. We present the CUBESPEC design and mission analysis, and give an update of the project status.