I wrote variable names and comments in Spanish when I started as my English level back then was very low.

Once my English improved and started to use English documentation and tutorials I just switched to write in English.

In my previous job I worked at software consultancy, I had coworkers who wrote code in Spanish but it wasn’t the norm.

Currently I work for an international company, the team is Spanish but we have to write everything in English as it can be shared with teams in other countries and audited by international organisations.

When AI tools were allowed, a lot of people use them in Spanish, it generates code with comments in Spanish. I had to reject a lot of PRs from the same guys over an over because everything must be in English.