oasdiff vs Smithy
oasdiff
oasdiff.com
Smithy
smithy.ioSide by side
| Figure | oasdiff | Smithy |
|---|---|---|
| Price from | $100/mo | — |
| Free plan | Yes | — |
| Free trial | Yes | — |
| Open source | — | — |
| Web | Yes | — |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| API | Yes | — |
| Self-hosted | Yes | — |
| Plans published | 3 | 0 |
| Spec score · API Design Tools | 8.5 (#8) | 7.1 (#24) |
| Purpose | oasdiff compares OpenAPI specifications, generates changelogs, and detects breaking changes before release. | Smithy is an open-source interface definition language for modeling services and SDKs. |
| Support | oasdiff provides support and security or procurement contact through [email protected]. | The CLI guide directs users with suggestions or issues to create an issue in the Smithy GitHub repository. |
Plans
In their own words
oasdiff
oasdiff compares OpenAPI specifications, produces changelogs, and identifies breaking changes before release. It supports OpenAPI 3.0, 3.1, and 3.2, and detects 755 distinct breaking and non-breaking API changes. The CLI is available through Homebrew, a shell installer, Docker, and pre-built Linux, macOS, and Windows binaries. Output formats include text, JSON, YAML, HTML, Markdown, and GitHub Actions annotations. Its GitHub Action compares pull-request and base-branch specifications, adding inline annotations for breaking changes. A browser diff tool compares OpenAPI or Swagger specifications without installation or sign-up. Specs and changelogs are encrypted client-side before upload, and servers retain ciphertext they cannot read. The open-source engine, CLI, and GitHub Action use the Apache 2.0 license. A free plan includes CLI diffing, changelogs, GitHub Action annotations, side-by-side review, and encrypted spec storage. Pro costs $100/month and adds approval workflow, audit trail, merge gate, and up to five reviewers across five repositories. Free review links expire after seven days; Enterprise can load specs from GitHub without uploading or storing them.