It's likely somebody getting confused between two different idioms.
get your feet wet
to become used to a new situation:
I worked as a substitute teacher for a while, just to get my feet wet.
get your hands dirty
1 to do physical work
She’d never get her hands dirty helping out around the house.
To work hard: work at, forge, overwork . . .
2 to become involved in something dishonest
To do something dishonest: cheat, defraud, falsify . . .
From the context of the passage, both get your feet wet and the first sense of get your hands dirty are possible. It's even possible that a combination of those two were meant and the hybrid phrase was used deliberately. However, I find that unlikely.
In short, I would not use the exact phrase that was used in the question. Instead, use one of the actual idioms.
The first means ease into things and the second means do some actual work (rather than just theory, in the context of programming).
They are not mutually exclusive. In theory, they could even be combined:
get your feet wet by getting your hands dirty
However, that sounds bizarre because they aren't meant to be combined that way.