Fastmail vs PostHog

Fastmail (Open-source software developed at Fastmail.) and PostHog (The single platform to analyze, test, observe, and deploy new features) both appear on the Smoower Developer Ecosystem Index.

PostHog (rank #30) holds a meaningful lead over Fastmail (rank #430) on the overall Smoower ecosystem score (63 vs 40). The gap of 23 points reflects composite signals across code, docs, community and reach.

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

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. PostHog shows 40,775 stars across 357 public repos, 87 active in the last 90 days and 212 external contributors. The star gap on its own does not decide the comparison, but PostHog's footprint is roughly 6.5x larger, which usually shows up in downstream signals like inbound issues and third party integrations.

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