This site is built entirely with free and open source software. It runs on WordPress using a lightly customized child theme of Primer. I use the self-hosted version of WordPress because it makes it easy to use any plugin, and to run multiple sites side by side (like my project site).
The header image (here and on my Twitter profile) is a severely cropped version of Nighthawks, a 1942 oil painting by Edward Hopper. My Dutch site features a less well-known scene of social interaction by Hopper: Chop Suey, made in 1929. Both images are in the public domain.
Publication lists are displayed using ZotPress (by Katie Seaborn) and a Zotero group library. This means listing papers is literally as easy as saving them in Zotero, the free and open source reference manager made by scholars for scholars. (Zotero is also the perfect tool for collecting, organizing and citing academic literature. Check out my Zotero tutorial here.)
Overviews of media coverage use data from the open altmetric service ImpactStory. ImpactStory, made by the wonderful people behind Our Research, collects news coverage and social media shares for any ORCID profile. ORCID is a nice and friendly free service that enables name disambiguation and can keep an authorative list of your scholarly output.
For basic visitor statistics I use Matomo, an excellent open source alternative for Google Analytics. IP addresses are anonymized and data never leaves the server. Some custom downloads (e.g. my CV) are managed with Download Monitor, making it easy to keep track of downloads of periodically updated files.