Data Science with a MicroMasters (EdX) by UCSD. I've completed two of four courses: Python for Data Science and Probability and Statistics.
The Python course was good and doable while working full time. I've had quite some experience with Python to get into it pretty easy, but learned a lot.
The Probability and Statistics course was hard for me and a big step outside my comfort zone. I cursed it a lot but I'm glad I completed it. I don't think I would have gone through with it if I hadn't payed for the certificate.
Next are Machine Learning Fundamentals, last but not least Big Data Analytics Using Spark.
I'm not really sure it made me a better (web) developer, but the process of learning keeps my brain fresh. Plus, it opens up a whole new and exciting world for me.
Yeah, nobody gets fired for buying IBM.
I don't know how the market for good developers is in Denmark, but I think restricting your potential employees to just formally trained limits your potential as team/company.
edit: Plus, I know quite a lot of formally trained developers who at some point just stopped learning. To me that is much more dangerous than not having a formal education in the first place.