Install Nix on Linux without root

nix-nonroot.md

Install Nix on Linux without root

Installing Nix without root is possible by using nix-user-chroot, which creates a user-space chroot and maps a writable directory to /nix. This allows Nix to work in environments where you cannot create or write to the real /nix path.

Reference:

• https://nixos.wiki/wiki/Nix_Installation_Guide#nix-user-chroot
• https://github.com/nix-community/nix-user-chroot

Install nix-user-chroot

Download the nix-user-chroot binary from the latest GitHub release and place it in ~/.local/bin.

# make sure local bin exists
mkdir -p ~/.local/bin

# install nix-user-chroot (replace <url> with the latest release URL)
curl -L -o ~/.local/bin/nix-user-chroot <url>
chmod +x ~/.local/bin/nix-user-chroot

# verify binary works
~/.local/bin/nix-user-chroot --help

Install Nix with directory mapping

nix-user-chroot maps your local directory (for example ~/.nix) to /nix inside the chrooted shell.

# create backing directory that will be mapped to /nix
mkdir -p ~/.nix

# optional: avoid toolchain issues in some HPC environments
unset LD_LIBRARY_PATH

# start a shell where ~/.nix is mapped to /nix
~/.local/bin/nix-user-chroot ~/.nix bash

# inside the chroot shell, verify mapping
ls -ald /nix
echo "Backed by: ~/.nix"

# run official Nix installer
curl -L https://nixos.org/nix/install | sh

Verify installation

Run these commands from inside the chroot shell after installation:

# load nix environment for current shell
. ~/.nix-profile/etc/profile.d/nix.sh

# check CLI is available
command -v nix

# show version
nix --version

# quick functional test
nix run nixpkgs#hello

Expected result:

• command -v nix returns a path under your home directory.
• nix --version prints the installed Nix version.
• nix run nixpkgs#hello prints Hello, world!.

Configure auto-loading in .zshrc

Add this snippet to your .zshrc so interactive shells automatically enter the mapped Nix environment.

# Auto-enter nix-user-chroot for interactive shells when not already inside mapped /nix
if [[ $- == *i* ]] && [ ! -d /nix ]; then
    CHROOT_BIN="$HOME/.local/bin/nix-user-chroot"
    NIX_BACKING_DIR="$HOME/.nix"

    if [ -x "$CHROOT_BIN" ] && [ -d "$NIX_BACKING_DIR" ]; then
        # Start zsh inside chroot and avoid re-loading global rc files repeatedly
        exec "$CHROOT_BIN" "$NIX_BACKING_DIR" zsh --no-global-rcs
    fi
fi

# Load Nix profile if available
if [ -f "$HOME/.nix-profile/etc/profile.d/nix.sh" ]; then
    . "$HOME/.nix-profile/etc/profile.d/nix.sh"
fi

Notes

• If your environment has strict module or compiler settings (common on HPC systems), you may need to unset variables like LD_LIBRARY_PATH before running Nix builds.
• You can leave the chroot shell with exit and re-enter later with:

~/.local/bin/nix-user-chroot ~/.nix zsh