Not in common-law jurisdictions, where an open source license without consideration is a bare license and can be revoked at will by the licensor.
Do you have a reference or, more preferably, casserole to share on this point?
Are you by any chance a Firefox user and you have auto-correct enabled?
I'm guessing that because of "casserole", which is what Firefox corrects to if you accidentally double the 's' in 'caselaw'. Chrome goes for "casual", and Safari goes for "caselaw".
It's a swype keyboard, I'm not always awake enough to catch the errors. Casserole is good too though! ;o)
In order for a contract to be valid, and enforceable on both sides, there has to be an offer, acceptance, and consideration. No consideration (payment), no contract, and the open source license reverts to what is known in law as a bare license. Bare licenses can be revoked at any time, at will, by the licensor, regardless of any promises made by the licensor to respect the license in perpetuity. (You can always tell a squatter to leave your property, regardless of how permissive you've been in the past.) This includes revoking the license to software downloaded under an open source license for which the licensee has given no consideration.
Only the license terms that the software is released under matter.
Most FOSS licenses include disclaimers like: "THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE."
If you did not pay the author for support, they do not owe you anything.
If they choose to provide support or fix reported bugs, that is their choice.
The NixOS team can use the code regardless of the developer's wishes if the license allows it.
If the developer chooses to not support the software on NixOS or change the license, that is their choice.
Additionally, the license is a contract (license don't exist as a separate category like in the US), the "[...] WHETHER IN AN ACTION OF CONTRACT" is particularly misplaced.
