15Five vs Customer IO

15Five and Customer IO both appear on the Smoower Developer Ecosystem Index.

Customer IO (rank #165) holds a modest lead over 15Five (rank #693) on the overall Smoower ecosystem score (51 vs 31). The gap of 20 points reflects composite signals across code, docs, community and reach.

On code quality (the state of repositories, tests, releases and polish), Customer IO is ahead of 15Five. On education (docs, guides and learning material for developers), Customer IO is clearly ahead of 15Five. On community (issue response, PR reviews and discussion health), Customer IO is slightly ahead of 15Five. On reach (how visible the ecosystem is beyond its own repos), Customer IO is clearly ahead of 15Five. On momentum (release cadence and how fast the ecosystem moves), Customer IO is ahead of 15Five.

15Five carries 141 GitHub stars across 29 public repos, with 2 repositories active in the last 90 days and 5 external contributors on record. Customer IO shows 684 stars across 107 public repos, 42 active in the last 90 days and 26 external contributors. The star gap on its own does not decide the comparison, but Customer IO's footprint is roughly 4.9x larger, which usually shows up in downstream signals like inbound issues and third party integrations.

15Five is worth a look for teams already invested in its stack. Customer IO looks better where reach is the deciding factor. The table below breaks the scores down pillar by pillar; the linked profiles cover the underlying repos, docs and community signals in full.