The workpieces in toolmaking are becoming increasingly complex and individualized. This complexity is transferred to the manufacturing process chains required for production. Thus, the cross-technology design of process chains is crucial in reducing costs and lead times while improving quality. The tool making industry applying a wide range of heterogeneous technologies further complicates this task. Process chain planning is usually done manually and intuitively, leading to a non-optimum solution without any alternatives. Existing feature-based approaches provide limited support for process plan-ning and fail on components with higher complexity. This paper presents a new ap-proach to automated process chain design using voxel-based workpiece models and evolutionary optimization. The goal is the generation of alternative technology chains, which are mapped utilizing a digital work plan. The planning depth can thus be increased, which is key in improving cross-technology effectiveness. The underlying methodology integrates considerations regarding kinematic accessibility to the machining point for different raw parts, clamping situations and tools. The methodology is structured in three consecutive phases. The first phase forms the analysis. It includes identifying all manufacturing technology information relevant for the process chain generation. Within the following design phase, models for describing work pieces and manufacturing technologies are developed. Based on these, different manufacturing technology strategies and their interdependencies can be mapped. In the conclusive decision phase, the technology chains are evaluated and optimized iteratively. The most suitable technology chains are transferred into a digital work plan. The digital work plan with specification of relevant manufacturing information provides the basis for decentralized communication between the workpiece and a manufacturing machine. The approach makes a significant contribution to the introduction of autonomous and adaptive manufacturing in toolmaking.