The "specialist vs. generalist" question is only one dimension. It would help if you could explain which business function you're interested in trying next. Th

The "specialist vs. generalist" question is only one dimension. It would help if you could explain which business function you're interested in trying next. The System/Sales Engineer role is flexible enough that you should be able to move laterally into a field services function (e.g. professional services or product support), or stay in the sales function and graduate to an [technical] account manager role with quota responsibilities. Breaking into product management/marketing or product development/engineering is generally easier at the same company because most people already know you. You'd have to convince them that you have the skills or to take a chance on you, and revealing your side project may help there (but be careful about the legal department asserting rights). Whether your new role & function combination will require you to become a specialist or generalist is usually role-dependent. Most small companies only have a single point product for sale, tending to force everybody into specific domain specialization, whereas larger companies usually have a suite of products allowing staff the choice to hop from product to product.