I drew a blank trying to identify this yellow boat, there was a fleet of them at St Gilgen on the Wolfgangsee, the hull has the look of a 12 Meter Sharpie, but the tall Bermudan sail definitely isn't.
Below, is this one of those classes that occurs around the world, each purpose-built for the specific location they sail in, ultra lightweight boat and with unfeasible large sail plan?
Needle thin and a towering mast presumably evolved for the relatively light winds and flat waters, it would be a blast to sail on one.
A modern interpretation on a similar theme the Esse 850, conceived to be sailed easily single-handed or by a small crew at fast speed without the ship heeling too much, the class became popular in the Swiss lakes and now has international fleets.
I guess there will be people saying it's a boat for middle aged men, I can see the attraction some fast, spirited sailing without too much drama.