SOAP (Spherical Overdensity and Aperture Processor) computes halo and galaxy properties from SWIFT (ascl:1805.020) simulations after being post-processed with a subhalo finder. The package takes a subhalo catalog as input and calculates a wide array of properties for each object. It offers parallel processing capabilities for efficient handling of large datasets, and allows for consistent property calculation across multiple halo finders. SOAP supports various halo definitions, including spherical overdensities and fixed physical apertures, providing flexibility for diverse observational comparisons. The package is compatible with both dark matter-only and full hydrodynamic simulations, producing HDF5 catalogues that are integrated with the swiftsimio package for seamless unit handling.