Car person is hard locked to Lani's highest level, thus it can only get to level 3 or 4 in the current version of the game (same thing for protagonist and party planner, which are attached to player max level and max combined party level).
Programmer is a title that can only be unlocked in dungeons, which is planned for release in version 0.2.10. So short answer is that there is no legit way to level those titles at this time.
If you're interested in future content like that, do visit the discord, I try to be pretty open about plans for titles and content, and a lot of player suggestions have already been included in current and planned game versions.