Abstract: We discuss the techniques for solving the topological string focussing on the recent progress in improving the high genus boundary conditions by considering the non-commutative resolutions of maximal unipotent monodromy points with Z2 torsion, the knowledge of modular D4-D2-D0 gauge theory indices and wall crossing formulas relating the latter to Donalsdon-Thomas, Pandharipande Thomas and finally Gopakunar Vafa invariants. The obtained high order perturbative results are used to confirm and extend analytic non-perturbative results based on resurgence techniques and in particular a transseries solution of the holomorphic anomaly equations.