Customer IO vs Slab

Customer IO and Slab (Making the workplace a source of learning and purpose through knowledge-sharing. We're hiring!) both appear on the Smoower Developer Ecosystem Index.

Customer IO (rank #165) holds a modest lead over Slab (rank #455) on the overall Smoower ecosystem score (51 vs 39). The gap of 12 points reflects composite signals across code, docs, community and reach.

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

Customer IO carries 684 GitHub stars across 107 public repos, with 42 repositories active in the last 90 days and 26 external contributors on record. Slab shows 49,433 stars across 28 public repos, 0 active in the last 90 days and 8 external contributors. The star gap on its own does not decide the comparison, but Slab's footprint is roughly 72.3x larger, which usually shows up in downstream signals like inbound issues and third party integrations.

Customer IO is the stronger read for anyone weighting momentum. Slab looks better where community 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.