Hey there,
A few months ago we open sourced Voiden, an offline API client we originally built to replace Postman internally. Voiden now has 12k+ downloads, 1k+ GitHub stars, and is growing every day. ❤️
Core principles we built it on:
- free and local-first
- file-based, all plain executable markdown
- composable through blocks
- collaboration in Git, where devs are already working
The main thing is that in Voiden, API requests are not static forms. They are built from blocks: endpoint, auth, params, body, scripts, and more. These blocks can be used, reused, replaced, and versioned in Git, just like code. And all of it lives in plain executable text.
Our inspiration was curl, because of how simple it is, and Obsidian, because of how powerful file-based workflows can become.
Who this is for:
- Developers, QA engineers, and technical writers working and collaborating on APIs.
Since open sourcing, almost everything we shipped came from actual users, feedback, and contributions that pushed the tool in a few interesting directions.
You can check our changelog here: https://voiden.md/changelog
A few highlights:
- Composable API workflows: reusable .void files that can be combined into flows
- Multiple requests in sequence
- Real scripting with JS, Python, and Shell before and after requests
- A skills layer so tools like Claude/Codex can operate directly on .void files and request blocks
- An SDK for community plugins
- And more…
This project is now mostly shaped and driven by community ideas and contributions. You’re welcome to join and help us make it even better.
There is no account setup. It’s free and totally offline.
GitHub: https://github.com/VoidenHQ/voiden
Download: https://voiden.md/download
This is cool! I’ve been using Bruno for a while now as an alternative. Maybe I’ll give this a go.
Awesome - would love some feedback !
I’ve never understood the point of postman. I usually just use curl
depends on the size of your team I guess? Postman used to really be the default API client for serious API testing. https://kaluvuri.com/blog/when-the-category-leader-stalls/
And yes curl is great and is a big inspiration for Voiden. In fact we built it inspired by curl and obsidian.
The problem I see with curl is that real API work is almost never just one request typed into a terminal like some kind of beautifully minimalist Unix haiku. It involves auth, environments, copied headers, reused payload fragments, request chains, documentation, testing, debugging, sharing examples with teammates, reviewing changes in Git, and trying not to break prod because you forgot to swap one token or one base URL.
At that point you can not “just use curl” right?. You use curl plus other things. Curl plus shell scripts, curl plus notes, curl plus env files, plus copied commands from Slack, plus random JSON files, plus tribal knowledge etc etc… Which is fine I guess but isnt it at some point super annoying and hard to collaborate on? That is the gap that I see this tool (Voiden) trying to solve.
So for me it is not “curl vs Voiden.” curl is a low-level execution tool. Voiden is a workspace for actual API work: writing requests, organizing them, reusing pieces, documenting them, testing them, versioning them in Git, and not duplicating the same headers/body/auth setup 45 times :)
does this resonate?