Germany’s start-up scene has plenty of reasons to feel good about itself.

While the country at large has flirted with recession, and corporate stalwarts from Daimler to Deutsche Bank are in trouble, the technology sector has had another good year. There have been headline-grabbing funding rounds, conferring $1bn-plus “unicorn” status on the likes of challenger bank N26 and travel start-up GetYourGuide. Software group TeamViewer pulled off the biggest stock market listing in Europe this year. Shares in online fashion retailer Zalando — the biggest business to emerge from Berlin’s start-up hothouse to date — have almost doubled in value since the start of the year.

Yet talk to founders and tech investors across the country, and you hear little complacency — and a whole lot of complaints. Some echo concerns that sound familiar to entrepreneurs in rival hubs, from soaring rents and a lack of affordable office space to the dearth of engineers. There is one gripe, however, that is specific to Germany — and which is the cause of growing anger and frustration: stock options, or the lack of them.