This is how you transfer to a software role when nobody knows who you are and you have nothing in production to show for it. You learn everything about company app X, and then you start at the bottom as 'customer support engineer' or even lower as 'customer happiness' or w/e they call it these days.

When you are not putting out fires of angry customers, you learn everything you can from the developers that work there even starting to write features, starting to find bugs, optimizing the software, creating new tooling, whatever. It's simple to transfer around internally, impossible to get in externally. Then from there you transfer into a developer role because now you're not just some unknown guy they don't want to risk hiring. Once you are no longer junior, meaning you put in the work at that imaginary place moving around roles internally you jettison out of there to the higher paying positions because now you're an experienced developer and probably have a little network you can use, in other words no longer a risk.