Duolingo vs Slab

Duolingo 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.

Duolingo (rank #338) holds a narrow lead over Slab (rank #455) on the overall Smoower ecosystem score (43 vs 39). The gap of 4 points reflects composite signals across code, docs, community and reach.

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

Duolingo carries 1,721 GitHub stars across 12 public repos, with 8 repositories active in the last 90 days and 11 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 28.7x larger, which usually shows up in downstream signals like inbound issues and third party integrations.

Duolingo is the stronger read for anyone weighting momentum. Slab looks better where code quality 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.