TASOPT.jl is a multi-disciplinary aircraft design and optimization code implemented in Julia (based on the original TASOPT by Mark Drela). It can currently model tube-and-wing aircraft using 2D viscous-inviscid CFD to calculate aerodynamic performance, simple beam bending theory to size the wings, and thermodynamic cycle modeling to calculate engine performance. Additionally new propulsion system options (e.g., fuel cells, ducted fans, electric machines) are available. New modelling capabilities are actively being developed, the github repository can be found here. Stable documentation can be found here. Please be sure to refer to the full documentation and dev notes before financing a new airframe development project.