
Downy Jumping Spider - side view, Loonse en Drunense Duinen, Netherlands
Very small (~5mm) and super active on this very hot day. As it does not have a very descriptive appearance, used external help to ID it. Some good info here (German):
https://wiki.arages.de/index.php?title=Attulus_pubescens
In dutch it is simply called "Hairy jumping spider", although it doesn't seem more hairy than other jumping spiders. I believe it may be related to the hairy palps.
Note the name change of the species. It was Sitticus pubescens until 2017, yet is now called Attulus pubescens.
Attulus pubescens is a jumping spider. The species have an angular head, and could be found in stone or inside houses.