It’s exactly what it says. Your nix config has a setting that has no effect without enabling the experimental feature that uses it. Either enable the feature, or remove the setting
None
You don't have the features "auto-allocate-uids" and "configurable-impure-env" enabled, so "auto-allocate-uids" and "impure-env" options are ignored in your config.
Check your nix.conf.
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Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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