Competition wallaha term applied in Anglo-Indian colloquial speech to a member of the Civil Service who obtained appointment by the competitive system instituted in 1856
Chambers's Twentieth Century Dictionary
Yule explains wālā as a Hindi adjectival affix, corresponding in a general way to the Latin -arius. Its usual employment as affix to a substantive makes it frequently denote agent, doer, keeper, owner, &c.
He hates competition-wallahs, being of the ancient muster himself.