Update: The FOSS fans can relax. it's just another partnership, insist GitHub CEO: https://www.theregister.co.uk/2019/05s/24/github_is_independent_despite_microsoft_acquisition_insists_ceo/.

The strategist behind all this: https://www.theregister.co.uk/2019/02/05/satya_nadella_five_years_microsoft_ceo/.