I've recently joined a startup. (I'm one of the first "employees", but not a founder). At the start, I was asked if I would like to work for money or for shares; I chose shares over money, because money was not an issue for me then. The founder, however, mentioned to pay a small bonus (of about $100) to all employees regardless of the contract we signed when the first (and then subsequent) stage of the project is completed. We have since then completed the project's first stage, but there hasn't been any mention of the bonus since. The shares contract I signed is very detailed, but it also doesn't conatain a word about the bonus.
The startup is very small and more like a group of friends than an actual workplace - however compensation has always been discussed individually and with proper privacy. I'm also not good at negotiating and talking about money in general. I'm also afraid that by asking I will mess up the management's attitude towards me. I do not want to come off as greedy - I've been viewing my participation in this project as "having fun" instead of "having to work", but I did so with full enthusiasm and dedication and I am convinced I actually did quality work and deserve the promised bonus.
Should I mention the issue? If yes, how? Please note I live in Hungary.