The present disclosure relates to methods for producing engineered eukaryotic cells by inducing modifications at target endogenous nucleic acid sequences. Methods disclosed herein may comprise introducing a transfection mixture into a eukaryotic cell via electroporation. In some embodiments, the transfection mixture may comprise a Cas9/sgRNA complex and a cell-free buffer. The Cas9/sgRNA complex may comprise a Cas9 protein and a sgRNA, wherein the sgRNA comprises a crRNA and a tracrRNA. Upon introduction into the eukaryotic cell, the Cas9/sgRNA complex of the transfection mixture may induce a modification of a target endogenous DNA sequence in the nucleus of the eukaryotic cell to provide for an engineered eukaryotic cell