First, what the <insert your own expression here>?

My expression would be "Kalen Delaney".

Ada Lovelace - possibly the first ever computer programmer.

Grace Hopper "the mother of Cobol"

Frances Allen - Won a Turing award. Not exactly small beer.

My wife's aunt was the highest ranking female officer in the Royal Navy during WWII. She was shipped all over the world installing, configuring RADAR plus training people to do the same. This is a women who at the age of 92 demonstrated to a TV repair man that the "broken" TV could be fixed by replacing a specific chip and soldering a loose connection!