Visualizing hourly activity

Hey, I'm building orgstats, an activity report for engineering organizations using data from GitHub.

I want to visualize the activity in the org by hour of the day. It should work for a single point in time (like a set timerange) but ideally also for data over time (think: activity by month by hour of day). I could be 2 different visualizations for a single point in time and data over time.

After some research, these are the two ideas I like the best:

1. clock-style Radar chart

Like this example

2. heat map

Like this example but with inverted axis and using hour of day instead of "town xyz"