A little less cloud. A lot more control.

Your APIs.
Your rules.

A proper API client. Native, local-first, and quietly powerful. Everything you need to send great requests. Nothing between you and your work.

v0.1.3 early access · Unsigned · macOS, Windows & Linux.

Less overhead. More headspace.Go on, send a request

Postern / Personal workspace All changes saved locally

GET Hello, worldDevelopment

GET {{base_url}}/v1/hello

KeyValueDescription

✓messagehello, developerA friendly introduction

Response

● 200 OK24 ms128 B

An interactive preview. Your real requests stay on your machine.Built with Go. Not a browser in disguise.

No account.No telemetry.No cloud required.Just you and your APIs.

A small footprint.
A full toolkit.

You shouldn’t have to choose between a capable API client and a tool that respects your space.

Actually native.

A real desktop app, built in Go. No Electron, no embedded browser, no extra runtime along for the ride.

One binary. Ready to work.

Private by default.

Your workspace lives on your disk. Add a passphrase-protected vault, or sync with end-to-end encryption. Your call.

Your data, not our business.

Fits your workflow.

Collections, environments, OAuth 2.0, and JavaScript tests. Bring your Postman collections. Keep your muscle memory.

Familiar where it matters.

Your workspace.
Not a subscription
to your workspace.

Work offline. Run collections from the terminal. Host your own sync server. Postern gives you the keys, and gets out of the way.

Explore the toolkit

~/your-workspacezsh

$ postern run GET api.example.com/health

200 OK · application/json

{
  "status": "healthy",
  "workspace": "yours"
}

$ postern run-collection "Smoke tests" \

--env Staging --fail-tests

✓ Authentication

✓ List users

✓ Create a request

3 requests. 3 passed. Back to building.

▍

Same engine. Desktop or command line.

A few good questions.

Can I bring my Postman collections?

Yes. Import and export Postman v2.1 collections, export environments, and copy requests as cURL. Your existing collections have a home here.

Do I need an account or internet connection?

No account is required for local work. Collections, environments, history, and scripts live on your computer. Sending requests only needs access to the API you’re calling.

Can I sync with my team?

Yes. Use the same upgraded self-hosted sync server, sign in with separate accounts, and open Settings → Team. Invite teammates as admins, editors, or viewers. Encrypted workspaces use a separate shared key; invitees choose their own workspace passphrase after entering a privately shared unlock code. No invitation email is sent. Set up team sync.

What does the sync server see?

With encrypted sync enabled, the server stores ciphertext, wrapped workspace keys, and account and routing metadata—not readable request contents. Unencrypted remotes remain readable to the server. Sync runs on demand or at intervals, not as live collaborative editing. Removing a member stops future sync access, not access to copies they already downloaded.

Can I switch themes and fold JSON?

Choose Light or Dark under Settings → General → Appearance. Request and response bodies support a JSON tree with object and array folding, Expand all, and Collapse all. Switch back to Edit JSON for requests or Raw for responses; folding never changes the underlying body.

What’s the current release status?

Postern v0.1.3 is an unsigned early-access testing release, not a stable production release. Download packages for macOS, Windows, and Linux—no Go or Make needed. macOS builds are not notarized, and Windows executables are not publisher-signed; operating-system security may block launch. Do not disable security protections. Back up before upgrading. Automatic updates, WebSocket, and gRPC tooling are not available. Downloads and installation guidance.

Keep your tools close.
Your data closer.

Send requests.
Not your data.

Local-first. Open source. Unapologetically yours.

Your APIs.Your rules.

A small footprint.A full toolkit.