Joiners, methods of joining, and related systems for additive manufacturing are provided. The method of joining includes bulk depositing, by an additive manufacturing tool head, a joiner (anchor) of a second material in a receptacle in a body of a first material. Also, the method of joining includes depositing an anchor layer of a third material upon the anchor. Networks of joiners in 3D printed parts, multi-material parts comprising joiners, computer program products for providing joiners, joiner systems including trolleys, and related methods and systems are also provided. Further provided is a system, and method, for securing a part to a build platform and separating the part from the build platform.