Credly
in order to see a full list of my badges please go to LinkedIn or Xing

Docker Hub
you find Jacksum on Docker there

Facebook
rarely used

Fosstodon

freeCodeCamp
coding challenges for web developers and certificates

GitHub
most of my free open source software is there

GitLab
nothing there, go to GitHub.

HackerRank
a great site with many coding challenges, it's fun and you can get badges!

johann.loefflmann.net
is my private homepage

LinkedIn
curriculum vitae, full certification list, etc.

Scrum.org
I really like agile frameworks

ScrumAlliance.org
I really like agile frameworks

sourceforge
a place with free open source software from my feather, ages before both GitHub and GitLab

Twitter
news about my applications

Xing
curriculum vitae, full certification list, etc.