Fastmail vs Klarna

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

Klarna (rank #257) holds a narrow lead over Fastmail (rank #430) on the overall Smoower ecosystem score (47 vs 40). The gap of 7 points reflects composite signals across code, docs, community and reach.

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

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. Klarna shows 2,965 stars across 139 public repos, 8 active in the last 90 days and 2 external contributors.

Fastmail is the stronger read for anyone weighting momentum. Klarna 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.