Fastmail vs Proton Mail

Fastmail (Open-source software developed at Fastmail.) and Proton Mail both appear on the Smoower Developer Ecosystem Index.

Proton Mail (rank #401) holds a narrow lead over Fastmail (rank #430) on the overall Smoower ecosystem score (41 vs 40). The gap of 1 points reflects composite signals across code, docs, community and reach.

On code quality (the state of repositories, tests, releases and polish), Proton Mail is clearly ahead of Fastmail. On education (docs, guides and learning material for developers), Fastmail is clearly ahead of Proton Mail. On community (issue response, PR reviews and discussion health), Proton Mail is ahead of Fastmail. On reach (how visible the ecosystem is beyond its own repos), Fastmail is clearly ahead of Proton Mail. On momentum (release cadence and how fast the ecosystem moves), Proton Mail is slightly 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. Proton Mail shows 16,265 stars across 186 public repos, 19 active in the last 90 days and 20 external contributors.

Fastmail is the stronger read for anyone weighting reach. Proton Mail 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.