Learn Turkish: Mühendis, verimliliği artırmak için çıldırırcasına kodluyordu. - The engineer was coding as if going crazy in order to increase productivity.

It attaches to the aorist (broad time) form of the verb. Here, çıldırmak (to go crazy) becomes çıldırır (goes crazy), and we add -casına to mean as if going crazy or like crazy. It describes an action done in an extreme or intense manner.

Why do we use artırmak instead of artmak here?

Artmak is intransitive and means to increase on its own (like when prices increase). Artırmak is the causative form, meaning to make something increase or to raise. Since the engineer is increasing something (productivity), we need the transitive artırmak and the accusative case on verimliliği.

What is the root of verimliliği and what suffixes are attached to it?

It comes from verim (yield or output). Adding -li makes verimli (productive), and -lik makes the noun verimlilik (productivity). Finally, because it is the specific direct object of artırmak, we add the accusative suffix -i, which softens the final k into ğ.

Why is it kodluyordu instead of kodlayordu?