\[ \left (x e^{y(x)}+e^x\right ) y'(x)+e^x y(x)+e^{y(x)}=0 \] ✓ Mathematica : cpu = 0.247981 (sec), leaf count = 33
\[\left \{\left \{y(x)\to c_1 e^{-x}-W\left (x e^{-x+c_1 e^{-x}}\right )\right \}\right \}\] ✓ Maple : cpu = 0.065 (sec), leaf count = 33
\[y \relax (x ) = \left (-\LambertW \left (x \,{\mathrm e}^{-x} {\mathrm e}^{-{\mathrm e}^{-x} c_{1}}\right ) {\mathrm e}^{x}-c_{1}\right ) {\mathrm e}^{-x}\]