37signals vs Calendly

37signals (HEY! It's in Basecamp!) and Calendly (Simple, beautiful scheduling.) both appear on the Smoower Developer Ecosystem Index.

37signals (rank #123) holds a meaningful lead over Calendly (rank #729) on the overall Smoower ecosystem score (54 vs 30). The gap of 24 points reflects composite signals across code, docs, community and reach.

On code quality (the state of repositories, tests, releases and polish), 37signals is clearly ahead of Calendly. On education (docs, guides and learning material for developers), 37signals is slightly ahead of Calendly. On community (issue response, PR reviews and discussion health), 37signals is clearly ahead of Calendly. On reach (how visible the ecosystem is beyond its own repos), 37signals is slightly ahead of Calendly. On momentum (release cadence and how fast the ecosystem moves), 37signals is clearly ahead of Calendly.

37signals carries 114,098 GitHub stars across 238 public repos, with 50 repositories active in the last 90 days and 285 external contributors on record. Calendly shows 132 stars across 29 public repos, 0 active in the last 90 days and 0 external contributors. The star gap on its own does not decide the comparison, but 37signals's footprint is roughly 864.4x larger, which usually shows up in downstream signals like inbound issues and third party integrations.

37signals is the stronger read for anyone weighting momentum. Calendly makes more sense for teams already using its adjacent tools. The table below breaks the scores down pillar by pillar; the linked profiles cover the underlying repos, docs and community signals in full.