I was raised in Galician but taught to read and write in Castillian (Spanish), and grew up in an environment where almost all media, signs, labelling, ..., were in Castillian. Programming related learning and work has taken most of my studying since my teen years, and I did that exclusively in English. Because of this, I estimate English is already the language in which I've done most of my reading and a fair share of my writing.

I can relate to what you say, because for quite a time when trying to express myself formally I used to end up resorting to a lot of transliterated Castillian constructs and phraseology. Other times, ideas would come in English and I'd try and find a Galician equivalent. I only got past that after a conscious decision to immerse myself in Galician and Portuguese literature. Sometimes I still feel like learning my native language as a second language.

And I'd be at a loss if I had to talk about programming related concepts in anything but English. I'd have to reinvent the vocabulary as I go. My own scribbled notes for personal use are written in a patois that is mostly Galician generously sprinkled with English.