I know that Cauldron.io does not have contributor information, but it should be possible with anonymized data to calculate the bus factor.
At least for Commits, I was able to build a visualization:
- Visualization: Pie Chart
- Index: git
- Slice Size: Count
- Split slice: author_id (Descending)
- (Activate) Group other values in separate bucket: TRUE
From this example, the Bus factor is 5 because it takes two committers to fill 50% of the circle.
Now, my request is to get the bus factor into the main user interface and maybe onto the Community section.