Fastmail vs Semrush

Fastmail (Open-source software developed at Fastmail.) and Semrush (We do love open source and have an opportunity to make it better from now.) both appear on the Smoower Developer Ecosystem Index.

Semrush (rank #317) holds a narrow lead over Fastmail (rank #430) on the overall Smoower ecosystem score (44 vs 40). 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), Semrush is ahead of Fastmail. On education (docs, guides and learning material for developers), Fastmail is slightly ahead of Semrush. On community (issue response, PR reviews and discussion health), Semrush is slightly ahead of Fastmail. On reach (how visible the ecosystem is beyond its own repos), Fastmail is clearly ahead of Semrush. On momentum (release cadence and how fast the ecosystem moves), Fastmail is slightly ahead of Semrush.

Fastmail carries 6,316 GitHub stars across 38 public repos, with 12 repositories active in the last 90 days and 2 external contributors on record. Semrush shows 454 stars across 11 public repos, 2 active in the last 90 days and 7 external contributors. The star gap on its own does not decide the comparison, but Fastmail's footprint is roughly 13.9x larger, which usually shows up in downstream signals like inbound issues and third party integrations.

Fastmail is the stronger read for anyone weighting reach. Semrush 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.