A system for additively manufacturing a composite part comprises a delivery guide, movable relative to a surface. The delivery guide is configured to deposit at least a segment of a continuous flexible line along a print path. The continuous flexible line comprises a non-resin component and a thermosetting-resin component. The thermosetting-resin component comprises a first part and a second part. The system further comprises a first resin-part applicator, configured to apply a first quantity of the first part to the non-resin component, and a second resin-part applicator, configured to apply a second quantity of the second part to the first quantity of the first part of a thermosetting resin, applied to the non-resin component. The system also comprises a feed mechanism, configured to pull the non-resin component through the first resin-part applicator and the second resin-part applicator, and to push the continuous flexible line out of the delivery guide.