An HTTP client for macOS 26.
Collections are JSON files in a folder you choose — no account, no cloud, nothing uploaded.
Download the DMG from Releases and drag Postfrau to Applications.
The app is ad-hoc signed, so macOS quarantines it. Either right-click → Open the first time, or clear the flag:
xattr -dr com.apple.quarantine /Applications/Postfrau.appIf macOS still refuses with "Postfrau is damaged", that is the quarantine flag — the command above fixes it.
- Request editor: params mirrored with the URL, headers, all auth schemes, every body mode
- Response viewer: pretty / raw / preview / headers / cookies, images and PDFs inline, hex for binary
- Collections and folders with inherited variables and auth
- Environments and globals; secrets live in the Keychain, never in the files
- History of every send, redacted by default
- Light, dark or follow-the-system, set per machine — the collections folder stays shared
- Sync by pointing the data folder at iCloud Drive, Dropbox or a git checkout
- Import OpenAPI 3.x; import/export Postman v2.1 and cURL, both directions
postfrauCLI that does all of the above from a shell, includingfindacross every request- A loopback API, so an agent in a sandbox that cannot read your files can still list and send
postfrau import openapi.json # OpenAPI 3.x, or a Postman collection/environmentOr File ▸ Import…, or drop the file on the sidebar.
An OpenAPI import produces a collection you can send from: servers[0] becomes {{baseUrl}},
tags become folders, path templates become {{variables}}, security becomes the collection's
auth, and bodies come from the spec's examples — or are synthesised from its schemas. JSON only;
convert YAML first with yq -o=json spec.yaml > spec.json.
postfrau find deposit balance # search names, paths, descriptions, URLs
postfrau get 'Acme API/Users/List users' # stored URL, resolved URL, what is unresolved
postfrau run 'Acme API/Users/List users' --env staging --var user_id=42 --json
postfrau send POST https://api.example.com/users -H 'Content-Type: application/json' -d '{"name":"Ada"}'
postfrau history --last 20Install it from Settings ▸ Advanced, or make install from a checkout.
For agents: postfrau skill install --to .claude/skills/postfrau writes a SKILL.md with the
commands, JSON shapes and exit codes.
Needs macOS 26, Xcode 26 and XcodeGen. No other dependencies.
make gen # generate the Xcode project
make build # app + CLI
make run
make test # 532 Core tests + app tests
make release # signed DMG in dist/Set CODESIGN_IDENTITY to sign with a Developer ID, NOTARY_PROFILE to notarize. Both optional.
| What | Where | Synced |
|---|---|---|
| Collections, environments, globals | the folder you choose | by your sync client |
| Secrets | login Keychain | only with iCloud Keychain on |
| History, settings, window state | app container | never |
No scripting, test assertions, mock server, team sync, WebSocket or gRPC.
MIT