1) I think its smart to cool down prior to having a conversation about the bonus. Approaching this tactfully will be important. 2) I'd absolutely call them out

1) I think its smart to cool down prior to having a conversation about the bonus. Approaching this tactfully will be important. 2) I'd absolutely call them out on this embarrassingly small bonus if only to establish that you're not going to take insults (which this is) laying down. 3) I'd probably not even bother fighting over the 4k annual bonus. I don't know what your current salary is but I'd imagine framing the argument as "I'm a RoR developer now" vs "I'm an under-rewarded support engineer" will be much more lucrative and any anchoring to the latter would only hurt that negotiation. I'd also keep in mind this bonus incident when negotiating your future role/salary/bonus structure with the company. 4) If they don't want to compensate you for your work, milk them for this experience since it sounds like a significant promotion in terms of responsibility and then run like mad to the next opportunity as soon as you find it (and you should start looking shortly if #3 doesn't play out favorably). Good luck!