Gaining a wholesome experience of starting a startup and not being limited to one role. Working directly with the founder who gave me 1st class mentorship. Independence regarding the company's sustainability report was a big challenge and responsibility that pushed me to work beyond work hours and be passionate about the topic.
What I wish was different
A more defined work structure which however is hard to establish in a seed stage startup.
Advice
Immerse yourself in the network you enter, the leaders will be there to back you up!