libDDD is C++ library for manipulation of decision diagrams. Main features include:Flexible and powerful encoding of operations using inductive homomorphisms; Support for hierarchy of the description with SDD; Automatic support for saturation style algorithms; A priori unbounded integer domain variables; Rich expressivity with equiv-split mechanism; Weak ordering constraint allowing to store variable length decision paths; Supports both Data Decision Diagrams which are integer valued and Hierarchical Set Decision Diagrams.