Freeze-dried is a term used for a glider constructible seed that can activated in some way to produce a complex object. For example, a "freeze-dried salvo" is a constellation of constructible objects which, when triggered by a single glider, produces a unidirectional glider salvo, and nothing else. Freeze-dried salvos can be useful in slow salvo constructions, especially when an active circuit has to destroy or reconstruct itself in a limited amount of time. Gradual modification by a construction arm may be too slow, or the circuit doing the construction may itself be the object that must be modified.
The concept may be applied to other types of objects. For example, one possible way to build a gun for a waterbear would be to program a construction arm to build a freeze-dried waterbear seed, and then trigger it when the construction is complete.