Comparison of the mass functions of the halo catalogues obtained by ASOHF (red), AHF (blue), Rockstar (green), and Subfind (orange) in the CAMELS Illustris–TNG LH–1 simulation at z = 0. Upper panel: mass functions obtained by each code, as solid lines. The thick purple line corresponds to a Tinker et al. (2008) mass function at z = 0 and with the cosmological parameters of the simulation for reference. Dashed lines present the mass function of subhaloes in the same colour scale. Lower panel: mass function of non-substructure haloes, normalised by the geometric mean of this statistic for the four halo finders. The shadow on the red line (ASOHF) corresponds to errors in halo counts. The errors are similar for the other finders.