CoSy (Coherent Systems) is an environment, by _(Bob Armstrong) based on _(APL). It's successor is KoSy, based on _(K).

It is somewhat interesting because of its Textual _(User Interface) (_(TUI)) resemblance with _(Oberon), _(The Humane Environment) and other similar systems.

<ul class="links">
  <li>_("Coherent Systems: CoSy.com" | http://cosy.com/).</li>
  <li>_("APL Forth bridge \| Create Ultimate NoteBook" | http://cosy.com/language/ultimate.htm).</li>
</ul>
