Calendly vs Duolingo

Calendly (Simple, beautiful scheduling.) and Duolingo both appear on the Smoower Developer Ecosystem Index.

Duolingo (rank #337) holds a modest lead over Calendly (rank #729) on the overall Smoower ecosystem score (43 vs 30). The gap of 13 points reflects composite signals across code, docs, community and reach.

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

Calendly carries 132 GitHub stars across 29 public repos, with 0 repositories active in the last 90 days and 0 external contributors on record. Duolingo shows 1,724 stars across 12 public repos, 8 active in the last 90 days and 11 external contributors. The star gap on its own does not decide the comparison, but Duolingo's footprint is roughly 13.1x larger, which usually shows up in downstream signals like inbound issues and third party integrations.

Calendly is the stronger read for anyone weighting education. Duolingo looks better where momentum 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.