.@ A zero-conditions libre software license

the 0lib license

Written by Tony Finch <dot@dotat.at> in Cambridge.

Permission is hereby granted to use, copy, modify, and/or
distribute this software for any purpose with or without fee.

This software is provided 'as is', without warranty of any kind.
In no event shall the authors be liable for any damages arising
from the use of this software.

SPDX-License-Identifier: 0BSD OR MIT-0


In the past I used the CC0 public domain dedication on my code, but it is problematic as a permissive open source license because it explicitly excludes a grant of patent rights. By contrast, the broad grants in the BSD, ISC, and MIT licenses are conventionally understood to include all patent and copyright permissions necessary for using the software. So I wanted to replace CC0 with something effectively as permissive as a public domain dedication, but less wordy than conventional licenses.


The license above uses the permission clause from the 0BSD license (which is actually a trimmed-down ISC license), and the disclaimer of warranty from the Zlib license. I adjusted the wording in a few places to match the MIT-0 license where the MIT wording is better. In particular,


This is a non-standard license, which is generally a bad idea. However I intend it to be an abbreviated summary of either 0BSD or MIT-0, either of which are fine for my purposes. So the SPDX line refers to them instead of using a custom LicenseRef tag.


The name is pronounced “zero lib”, taking the 0 from 0BSD and the lib from Zlib, and retconned to be short for “a zero-conditions libre software license”.