We present an algorithm to evaluate multiloop Feynman integrals with an arbitrary number of internal massive lines, with the masses being in general complex-valued, and its implementation in the Mathematica package SeaSyde. The implementation solves by series expansions the system of differential equations satisfied by the Master Integrals. At variance with respect to other existing codes, the analytical continuation of the solution is performed in the complex plane associated to each kinematical invariant. We present the results of the evaluation of the Master Integrals relevant for the NNLO QCD-EW corrections to the neutral-current Drell-Yan processes. Program Title:SeaSyde CPC Library link to program files:https://doi.org/10.17632/4hk9rbw4y8.1 Developer's repository link:https://github.com/TommasoArmadillo/SeaSyde Licensing provisions: GPLv3 Programming language:Mathematica Nature of problem: Solution of multi-loop Feynman integrals with an arbitrary number of internal complex-valued massive lines. Solution method:: Solution via series expansions of the systems of differential equations satisfied by the loop integrals. Analytic continuation of the solution to any point of the kinematic variables. The solution is transported from the initial to the final point, by moving in the complex plane associated to each kinematic variable. In multi-variable problems, the transport is computed one variable at the time.
