WaveSep — a wavelet-based iterative approach for susceptibility source separation. It splits net susceptibility (χ_total/QSM) into paramagnetic (χ+, iron) and diamagnetic (χ−, myelin·calcium) sources using an R2' map to break the para/dia degeneracy, under two voxel-wise data-fidelity terms (χ+ + χ− ≈ χ_total, χ+ − χ− ≈ R2'/Dr) and a wavelet-domain L1 sparsity prior solved by proximal gradient (soft-thresholding, db4). Pure Python on CPU — no network, no pretrained weights, no GPU. QSM-CI reconstruction method wavesep. Browse and run it at https://qsmxt.github.io/QSM-CI/submission.html?method=wavesep.