A plan to expand a physical backup of the world’s most widely used open-source software held inside a mountain in the Arctic will go ahead this month, despite the coronavirus pandemic .

GitHub, an online software host owned by Microsoft, has already stored the equivalent of 10,000 folders of source code files in Coal Mine 3, a disused facility on the island of Spitsbergen in Svalbard, Norway.

This month, the company will hugely expand its existing storage by adding repositories that can hold …