Augusta Ada King, Countess of Lovelace, better known these days as Ada Lovelace, is often regarded as the world's first computer programmer. She worked with Charles Babbage in the early 1840s when he was planning his Analytical Engine, which would've been the world's first programmable computer if it had ever been completed.
In the Wikipedia entry on Babbage, it says:
[Ada Lovelace] wrote several programs in what would today be called assembly language for the analytical engine, but which were never actually executed. [She] is therefore considered the world's first computer programmer, at least in the theoretical sense.
And that fits what I've always heard about her. But the Wikipedia entry on Lovelace herself (I'm not sure how best to refer to her) says:
Ada translated for Babbage Italian mathematician Louis Menebrea's memoir on Babbage's newest proposed machine, the Analytical Engine. With the article, she appended a set of Notes which specified in complete detail a method for calculating Bernoulli numbers with the Engine, recognized by historians as the world's first computer program. Biographers note, however, that the programs were written by Babbage himself, and Lovelace simply found a mistake in the program for calculating Bernoulli numbers and sent it back for amendment. The evidence and correspondence between Lovelace and Babbage indicate that he wrote all of the programs in the notes appended to the Menebrea translation. Her prose acknowledged some possibilities of the machine which Babbage never published....
I don't know how true that is; Wikipedia is not necessarily the best-researched source in the world, and the article goes on to add, "As an early woman in computing, Lovelace occupies a politically sensitive space in the canon of historical figures in computer science, and therefore the extent of her contribution versus Babbage's remains difficult to assess based on current sources." But if it's really true that Ada wrote up notes on Babbage's programs and pointed out bugs in them, that would suggest to me that she really ought to be known as the world's first software-oriented technical writer.
Or possibly the world's first Quality Assurance person. But it sounds more like tech writing to me. And y'know, in startups sometimes people have to wear multiple hats.