I was in your situation 20 years ago, as a postdoc in Theoretical Physics. My advice is to contribute to some known Open Source project, so that you have some provable programming skills when entering the job market. In my case I contributed to Python, not by coding, but by writing various articles on advanced features of the language and an essay on the Method Resolution Order that at the time was new and undocumented. Guido van Rossum in person put that essay on the official Python site. Having something like that in your CV helps when looking for an IT job. Nowadays I would probably contribute to Julia, you need something that shows promises but it is not mainstream yet to make a good impression.