If you wanted to re-read my post about the various technical roles a co-founder can take as a startup grows in Russian, you can, here. Thanks to Vlad for the translation.
Bonus! Here’s discussion on Hacker News, including my favorite comment:
Having been on both sides of the situation a couple times, the distinction is pretty simple for me: do you have a seat on the board?
If you have a board seat, great, you’re a real founder/CTO!
If you’re not interested in the board seat or you’re aware that you don’t bring enough to the table to earn it, you’re a good candidate for a founding engineer. You should be happy!
If the other founder(s) want you to be a founder/CTO without the board seat, run! They’re just using the prestige of the title to pay you less, and will revoke it at the first convenience.