Uploaded February 2026 | Updated September 2026, 2 weeks ago
Ned Batchelder (nedbat), creator and long-time maintainer of coverage.py, joins Push to Talk | Meet the Maintainers to share his path into programming and open source and the real story behind one of Python’s most popular testing tools. We talk about the journey to coverage.py, the turning points that shaped it, and why the measurement of the library is only 94%.
What's inside?
0:00 Intro
00:55 Getting into programming
01:30 Why open source
02:25 The origin story of coverage.py
03:55 Did you expect coverage.py to take off?
04:55 How coverage.py works (in one paragraph)
06:40 Unusual and quirky use cases
07:30 Performance impact in production
07:50 Coverage targets and chasing numbers
09:05 Coverage.py’s own coverage percentage
10:45 Toughest technical challenges and bugs
11:40 Computer science problems behind coverage.py
12:50 Working with the coverage.py community
13:45 Trusting outside help and issue triage
14:25 Saying no to feature requests
16:25 coverage.py vs pytest-cov
17:40 If coverage.py had a personality
18:05 The sleepy snake mascot story
18:50 A message to the community
Surprise us: how are you using coverage.py?
Want to know more about open source libraries and their maintainers? Read our blog: ubuntu.com/blog/the-foundations-of-software-open-source-libraries-and-their-maintainers
Ned Batchelder (nedbat), creator and long-time maintainer of coverage.py, joins Push to Talk | Meet the Maintainers to share his path into programming and open source and the real story behind one of Python’s most popular testing tools. We talk about the journey to coverage.py, the turning points that shaped it, and why the measurement of the library is only 94%.
What's inside?
0:00 Intro
00:55 Getting into programming
01:30 Why open source
02:25 The origin story of coverage.py
03:55 Did you expect coverage.py to take off?
04:55 How coverage.py works (in one paragraph)
06:40 Unusual and quirky use cases
07:30 Performance impact in production
07:50 Coverage targets and chasing numbers
09:05 Coverage.py’s own coverage percentage
10:45 Toughest technical challenges and bugs
11:40 Computer science problems behind coverage.py
12:50 Working with the coverage.py community
13:45 Trusting outside help and issue triage
14:25 Saying no to feature requests
16:25 coverage.py vs pytest-cov
17:40 If coverage.py had a personality
18:05 The sleepy snake mascot story
18:50 A message to the community
Surprise us: how are you using coverage.py?
Want to know more about open source libraries and their maintainers? Read our blog: ubuntu.com/blog/the-foundations-of-software-open-source-libraries-and-their-maintainers
