# NixOS This document contains general notes about NixOS that are independent of my NixOS configuration. ## Table of Contents * [NixOS](#nixos) * [Table of Contents](#table-of-contents) * [Misc](#misc) * [NixOS upgrades](#nixos-upgrades) * [niv: Dependency management](#niv-dependency-management) * [Add Home Manager with niv](#add-home-manager-with-niv) * [Add NUR with niv](#add-nur-with-niv) * [System information](#system-information) * [Customize a NixOS package with override or nix-build](#customize-a-nixos-package-with-override-or-nix-build) * [Search for packages](#search-for-packages) * [Search for options](#search-for-options) * [Search which package owns a file](#search-which-package-owns-a-file) * [List files of package](#list-files-of-package) * [Package runtime dependency report](#package-runtime-dependency-report) * [Nix profiles](#nix-profiles) * [Switch to previous system profile](#switch-to-previous-system-profile) * [List system profiles](#list-system-profiles) * [Deleting generations - Keep most recent X system profiles](#deleting-generations---keep-most-recent-x-system-profiles) * [Garbage collection - Delete unreachable store objects](#garbage-collection---delete-unreachable-store-objects) * [why-depends: Why is a package/dependency installed](#why-depends-why-is-a-packagedependency-installed) * [Compare two system profiles](#compare-two-system-profiles) * [NixOS configuration debugging](#nixos-configuration-debugging) * [Show Nix configuration](#show-nix-configuration) * [Evaluate NixOS configuration to JSON](#evaluate-nixos-configuration-to-json) * [Evaluate expressions in the context of a NixOS configuration managed with Colmena](#evaluate-expressions-in-the-context-of-a-nixos-configuration-managed-with-colmena) * [Evaluate expressions](#evaluate-expressions) * [Escape strings](#escape-strings) * [Run AppImages](#run-appimages) * [Audio troubleshooting - Realtek ALC898 Audio Codec on ASRock Z77 Extreme 4](#audio-troubleshooting---realtek-alc898-audio-codec-on-asrock-z77-extreme-4) * [Graphic drivers](#graphic-drivers) * [XDG mimes, desktop files](#xdg-mimes-desktop-files) * [Additional resources](#additional-resources) * [Nix Pills](#nix-pills) * [Papers](#papers) ## Misc * There is controversy about flakes, rather use channels (e.g. with niv) ## NixOS upgrades See [NixOS Upgrades](NixOS%20Upgrades.md). ## niv: Dependency management * https://nix.dev/tutorials/first-steps/towards-reproducibility-pinning-nixpkgs#dependency-management-with-niv niv: > Easy dependency management for Nix projects. > > Nix is a very powerful tool for building code and setting up environments. niv complements it by making it easy to > describe and update remote dependencies (URLs, GitHub repos, etc). It is a simple, practical alternative to Nix > flakes. > > https://github.com/nmattia/niv > Niv is an easy dependency management for Nix projects with package pinning. > > https://github.com/mikeroyal/NixOS-Guide Initialize: ```shell niv init ``` Change the tracking branch of nixpkgs from unstable to 23.05: ```shell niv modify nixpkgs --branch nixos-23.05 ``` Add nixpkgs unstable: ```shell niv add NixOS/nixpkgs -n unstable -b nixpkgs-unstable ``` ### Add Home Manager with niv Home Manager: > [Home Manager] allows declarative configuration of user specific (non-global) packages and dotfiles. > > To avoid breaking users' configurations, Home Manager is released in branches corresponding to NixOS releases ( > e.g. `release-23.05`). > > Home Manager provides both the channel-based setup and the flake-based one. > > https://github.com/nix-community/home-manager Check your channel: ```shell sudo nix-channel --list #=> nixos https://nixos.org/channels/nixos-23.05 ``` Use the corresponding branch: ```shell niv add nix-community/home-manager -n home-manager -b release-23.05 ``` ### Add NUR with niv > The Nix User Repository (NUR) is community-driven meta repository for Nix packages. > > ... packages are built from source and are not reviewed by any Nixpkgs member. > > https://github.com/nix-community/NUR ```shell niv add nix-community/NUR -n NUR ``` ## System information ```shell nix-info -m ``` ``` - system: `"x86_64-linux"` - host os: `Linux 6.1.51, NixOS, 23.05 (Stoat), 23.05.3242.da5adce0ffaf` - multi-user?: `yes` - sandbox: `yes` - version: `nix-env (Nix) 2.13.5` - channels(root): `"nixos-23.05"` - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos` ``` ## Customize a NixOS package with override or nix-build See https://codeberg.org/privacy1st/nix-build-and-override-docs ## Search for packages * https://search.nixos.org/packages ## Search for options * https://search.nixos.org/options * Or `man configuration.nix` * https://mipmip.github.io/home-manager-option-search * Or `man home-configuration.nix` ## Search which package owns a file ```shell # Note how your shell prefix changes. nix-shell -p nix-index ``` ```shell # Either build the index manually (requires >12GB RAM): nix-index # Or download weekly build: mkdir -p ~/.cache/nix-index/ && wget -q -N https://github.com/nix-community/nix-index-database/releases/latest/download/index-x86_64-linux -O ~/.cache/nix-index/files # Then search for a file nix-locate --whole-name '/bash' ``` ## List files of package * https://discourse.nixos.org/t/list-files-of-package/25830/2 Example for `nano`: ```shell find $(nix-build '' -A nano --no-link) ``` Excerpt of the result: ``` /nix/store/jqvxmx65mfinbsm6db9kmcqmphl44xhp-nano-7.2/share/nano /nix/store/jqvxmx65mfinbsm6db9kmcqmphl44xhp-nano-7.2/share/nano/asm.nanorc /nix/store/jqvxmx65mfinbsm6db9kmcqmphl44xhp-nano-7.2/share/nano/autoconf.nanorc ``` ## Package runtime dependency report - https://github.com/nix-how/nix-demos#runtimereport -> https://www.nmattia.com/posts/2019-10-08-runtime-dependencies/ Example: Licenses and maintainers of runtime dependencies of package `hello`: ```shell nix --extra-experimental-features flakes --extra-experimental-features nix-command bundle --bundler github:nix-how/nix-demos#runtimeReport nixpkgs#hello cat hello-*-report ``` ```console --------------------------------- | OFFICIAL REPORT | | requested by: the lawyers | | written by: yours truly | | TOP SECRET - TOP SECRET | --------------------------------- runtime dependencies of hello-2.12.1: - libunistring-1.1 (lgpl3Plus) maintained by - xgcc-13.2.0 (gpl3Plus) maintained by Patrick Hilhorst, Vladimír Čunát, John Ericson - hello-2.12.1 (gpl3Plus) maintained by Eelco Dolstra - libidn2-2.3.4 (lgpl3Plus, gpl2Plus, gpl3Plus) maintained by Franz Pletz - glibc-2.38-27 (lgpl2Plus) maintained by Eelco Dolstra, Maximilian Bosch, Connor Baker ``` Example: `nano` ```console --------------------------------- | OFFICIAL REPORT | | requested by: the lawyers | | written by: yours truly | | TOP SECRET - TOP SECRET | --------------------------------- runtime dependencies of nano-7.2: - libunistring-1.1 (lgpl3Plus) maintained by - file-5.45 (bsd2) maintained by Doron Behar - xgcc-13.2.0 (gpl3Plus) maintained by Patrick Hilhorst, Vladimír Čunát, John Ericson - nano-7.2 (gpl3Plus) maintained by Joachim Fasting, Tim Steinbach - libidn2-2.3.4 (lgpl3Plus, gpl2Plus, gpl3Plus) maintained by Franz Pletz - zlib-1.3 (zlib) maintained by nobody - glibc-2.38-27 (lgpl2Plus) maintained by Eelco Dolstra, Maximilian Bosch, Connor Baker - ncurses-6.4 (mit) maintained by nobody ``` Example: `firefox` ```console --------------------------------- | OFFICIAL REPORT | | requested by: the lawyers | | written by: yours truly | | TOP SECRET - TOP SECRET | --------------------------------- runtime dependencies of firefox-121.0.1: - libunistring-1.1 (lgpl3Plus) maintained by - perl5.38.2-WWW-RobotRules-6.02 (artistic1, gpl1Plus) maintained by nobody - gdbm-1.23 (gpl3Plus) maintained by Rahul Gopinath - perl5.38.2-HTTP-CookieJar-0.014 (asl20) maintained by nobody - gmp-with-cxx-6.3.0 (lgpl3Only, gpl2Only) maintained by Rahul Gopinath - libXdamage-1.1.6 (no license) maintained by nobody - expat-2.5.0 (mit) maintained by nobody - gnutls-3.8.2 (lgpl21Plus) maintained by Vladimír Čunát - dbus-1.14.10 (gpl2Plus) maintained by Jan Tojnar - systemd-minimal-libs-254.6 (lgpl21Plus) maintained by Florian Klink, Finn Behrens - gnutar-1.35 (gpl3Plus) maintained by - util-linux-minimal-2.39.3 (gpl2Only, gpl2Plus, gpl3Plus, lgpl21Plus, bsd3, bsdOriginalUC, publicDomain) maintained by nobody - gdk-pixbuf-2.42.10 (lgpl21Plus) maintained by Eelco Dolstra, Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey - tracker-3.6.0 (gpl2Plus) maintained by Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey - libXext-1.3.5 (no license) maintained by nobody - openssl-3.0.12 (asl20) maintained by Markus Theil - at-spi2-core-2.50.0 (lgpl21Plus) maintained by Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey, Michael Raskin - libXtst-1.2.4 (no license) maintained by nobody - gcc-13.2.0 (gpl3Plus) maintained by Patrick Hilhorst, Vladimír Čunát, John Ericson - bzip2-1.0.8 (bsdOriginal) maintained by Jörg Thalheim - perl5.38.2-TimeDate-2.33 (artistic1, gpl1Plus) maintained by nobody - libsoup-3.4.4 (lgpl2Plus) maintained by Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey, Jason O'Conal, Michael Raskin - dconf-0.40.0 (lgpl21Plus) maintained by Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey - cairo-1.18.0 (lgpl2Plus, mpl10) maintained by nobody - libxcrypt-4.4.36 (lgpl21Plus) maintained by Misha Gusarov, Martin Weinelt - libxml2-2.12.3-unstable-2023-12-14 (mit) maintained by Eelco Dolstra, Jan Tojnar - libffi-3.4.4 (mit) maintained by Matthew Bauer - perl5.38.2-Test-Fatal-0.017 (artistic1, gpl1Plus) maintained by nobody - gcc-13.2.0 (gpl3Plus) maintained by Patrick Hilhorst, Vladimír Čunát, John Ericson - libnetfilter_conntrack-1.0.9 (gpl2Plus) maintained by nobody - shadow-4.14.2 (bsd3) maintained by nobody - util-linux-minimal-2.39.3 (gpl2Only, gpl2Plus, gpl3Plus, lgpl21Plus, bsd3, bsdOriginalUC, publicDomain) maintained by nobody - zstd-1.5.5 (bsd3) maintained by Orivej Desh - libyaml-0.2.5 (mit) maintained by nobody - db-4.8.30 (sleepycat) maintained by nobody - json-c-0.17 (mit) maintained by Jason O'Conal - avahi-0.8 (lgpl2Plus) maintained by Jason O'Conal, Robin Gloster - libXfixes-6.0.1 (no license) maintained by nobody - libsoup-2.74.3 (lgpl2Plus) maintained by Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey, Jason O'Conal, Michael Raskin - libapparmor-3.1.6 (gpl2Only, lgpl21Only) maintained by Julien Moutinho, Austin Seipp, Andreas Schrägle, Janne Heß - cups-2.4.7 (asl20) maintained by Matthew Bauer - wayland-1.22.0 (mit) maintained by Michael Weiss, Cody Opel, Alyssa Ross - libXrandr-1.5.4 (no license) maintained by nobody - cryptsetup-2.6.1 (gpl2) maintained by Ryan Lahfa - nghttp2-1.57.0 (mit) maintained by Renaud - file-5.45 (bsd2) maintained by Doron Behar - gtk+3-3.24.39 (lgpl2Plus) maintained by Michael Raskin, Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey - giflib-5.2.1 (mit) maintained by - gmp-with-cxx-6.3.0 (lgpl3Only, gpl2Only) maintained by Rahul Gopinath - libselinux-3.3 (gpl2Plus) maintained by - freetype-2.13.2 (gpl2Plus) maintained by Thomas Tuegel - graphite2-1.3.14 (lgpl21) maintained by Michael Raskin - bash-5.2-p21 (gpl3Plus) maintained by Will Dietz - perl5.38.2-Net-HTTP-6.23 (artistic1, gpl1Plus) maintained by nobody - xkeyboard-config-2.40 (no license) maintained by nobody - audit-3.1.2 (gpl2Plus) maintained by Anderson Torres - libXrender-0.9.11 (no license) maintained by nobody - gnum4-1.4.19 (gpl3Plus) maintained by nobody - libdeflate-1.19 (mit) maintained by Orivej Desh, Dmitry Bogatov - perl5.38.2-HTTP-Cookies-6.10 (artistic1, gpl1Plus) maintained by nobody - fribidi-1.0.13 (lgpl21) maintained by nobody - libfido2-1.14.0 (bsd2) maintained by Will Dietz, Pavol Rusnak - libuv-1.47.0 (mit, isc, bsd2, bsd3, cc-by-40) maintained by Mario Rodas - python3-3.11.7 (psfl) maintained by Frederik Rietdijk - xgcc-13.2.0 (gpl3Plus) maintained by Patrick Hilhorst, Vladimír Čunát, John Ericson - libmnl-1.0.5 (lgpl21Plus) maintained by nobody - util-linux-minimal-2.39.3 (gpl2Only, gpl2Plus, gpl3Plus, lgpl21Plus, bsd3, bsdOriginalUC, publicDomain) maintained by nobody - libthai-0.1.29 (lgpl21Plus) maintained by - gawk-5.2.2 (gpl3Plus) maintained by - libXmu-1.1.4 (no license) maintained by nobody - unbound-1.19.0 (bsd3) maintained by Andreas Schrägle, Janne Heß - perl5.38.2-HTTP-Message-6.45 (artistic1, gpl1Plus) maintained by nobody - libbpf-1.3.0 (lgpl21, bsd2) maintained by Austin Seipp, Vladimír Čunát, Sascha Grunert, Dominique Martinet - pixman-0.42.2 (mit) maintained by nobody - libXft-2.3.8 (no license) maintained by nobody - libGL-1.7.0 (mit, bsd1, bsd3, gpl3Only, asl20) maintained by nobody - firefox-121.0.1 (mpl20) maintained by Bernardo Meurer, Martin Weinelt - util-linux-minimal-2.39.3 (gpl2Only, gpl2Plus, gpl3Plus, lgpl21Plus, bsd3, bsdOriginalUC, publicDomain) maintained by nobody - perl5.38.2-Clone-0.46 (artistic1, gpl1Plus) maintained by nobody - iptables-1.8.10 (gpl2) maintained by Franz Pletz - libssh2-1.11.0 (bsd3, libssh2) maintained by Sandro Jäckel - systemd-minimal-254.6 (lgpl21Plus) maintained by Florian Klink, Finn Behrens - icu4c-73.2 (no license) maintained by Michael Raskin - pango-1.51.0 (lgpl2Plus) maintained by Michael Raskin, Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey - libmicrohttpd-0.9.71 (lgpl2Plus) maintained by Eelco Dolstra, Rahul Gopinath, Franz Pletz - libcbor-unstable-2023-01-29 (mit) maintained by Will Dietz - attr-2.5.1 (gpl2Plus) maintained by nobody - perl5.38.2-HTML-Parser-3.81 (artistic1, gpl1Plus) maintained by nobody - libSM-1.2.4 (no license) maintained by nobody - libpng-apng-1.6.40 (libpng2) maintained by Vladimír Čunát - glib-2.78.3 (lgpl21Plus) maintained by Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey, Jason O'Conal, Michael Raskin - gsettings-desktop-schemas-45.0 (lgpl21Plus) maintained by Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey - nettle-3.9.1 (gpl2Plus) maintained by Vladimír Čunát - perl5.38.2-HTTP-Date-6.06 (artistic1, gpl1Plus) maintained by nobody - libusb-1.0.26 (lgpl21Plus) maintained by Pavol Rusnak, Ido Samuelson - libargon2-20190702 (asl20, cc0) maintained by Taeer Bar-Yam, Owen Lynch - brotli-1.1.0 (mit) maintained by freezeboy - glibc-2.38-27 (lgpl2Plus) maintained by Eelco Dolstra, Maximilian Bosch, Connor Baker - libcap-ng-0.8.3 (lgpl21) maintained by nobody - libnftnl-1.2.6 (gpl2Plus) maintained by Franz Pletz, Andreas Schrägle, Janne Heß - libxcb-1.16 (no license) maintained by nobody - glibc-2.38-27 (lgpl2Plus) maintained by Eelco Dolstra, Maximilian Bosch, Connor Baker - libpcap-1.10.4 (bsd3) maintained by Franz Pletz - libXt-1.3.0 (no license) maintained by nobody - publicsuffix-list-unstable-2023-02-16 (mpl20) maintained by Renaud - libepoxy-1.5.10 (mit) maintained by Cillian de Róiste - libX11-1.8.7 (no license) maintained by nobody - keyutils-1.6.3 (gpl2Plus) maintained by nobody - libXcursor-1.2.1 (no license) maintained by nobody - fontconfig-2.14.2 (bsd2) maintained by Jan Tojnar - tzdata-2023d (bsd3, publicDomain) maintained by Andreas Schrägle, Franz Pletz - tpm2-tss-4.0.1 (bsd2) maintained by Arthur Gautier - libxkbcommon-1.5.0 (mit) maintained by Michael Weiss, Thomas Tuegel - bash-interactive-5.2-p21 (gpl3Plus) maintained by Will Dietz - sqlite-3.44.2 (publicDomain) maintained by Eelco Dolstra, Nicolas Pouillard - perl5.38.2-XML-Parser-2.46 (artistic1, gpl1Plus) maintained by nobody - perl5.38.2-HTTP-Daemon-6.16 (artistic1, gpl1Plus) maintained by nobody - getent-glibc-2.38-27 (no license) maintained by nobody - libcap-2.69 (bsd3) maintained by nobody - xz-5.4.5 (gpl2Plus, lgpl21Plus) maintained by Sander van der Burg - perl5.38.2-Test-Needs-0.002010 (artistic1, gpl1Plus) maintained by nobody - perl5.38.2-File-Listing-6.16 (artistic1, gpl1Plus) maintained by nobody - libdatrie-2019-12-20 (lgpl21Plus) maintained by - readline-8.2p7 (gpl3Plus) maintained by Will Dietz - libXcomposite-0.4.6 (no license) maintained by nobody - perl5.38.2-IO-HTML-1.004 (artistic1, gpl1Plus) maintained by nobody - coreutils-9.4 (gpl3Plus) maintained by Janne Heß - dejavu-fonts-minimal-2.37 (free) maintained by nobody - glib-2.78.3 (lgpl21Plus) maintained by Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey, Jason O'Conal, Michael Raskin - libpsl-0.21.2 (mit) maintained by Renaud - libgpg-error-1.47 (lgpl2Plus) maintained by Rahul Gopinath - libnl-3.8.0 (lgpl21) maintained by Franz Pletz - openssl-3.0.12 (asl20) maintained by Markus Theil - pcre-8.45 (bsd3) maintained by - perl5.38.2-Try-Tiny-0.31 (mit) maintained by nobody - libidn2-2.3.4 (lgpl3Plus, gpl2Plus, gpl3Plus) maintained by Franz Pletz - libtool-2.4.7 (gpl2Plus) maintained by - p11-kit-0.25.3 (bsd3) maintained by nobody - harfbuzz-7.3.0 (mit) maintained by Eelco Dolstra - gnugrep-3.11 (gpl3Plus) maintained by Janne Heß, Moritz Lumme - zlib-1.3 (zlib) maintained by nobody - gnused-4.9 (gpl3Plus) maintained by Jörg Thalheim - libXdmcp-1.1.4 (no license) maintained by nobody - libnfnetlink-1.0.2 (gpl2) maintained by nobody - libevent-2.1.12 (bsd3) maintained by nobody - libICE-1.1.1 (no license) maintained by nobody - libmd-1.1.0 (bsd3, bsd2, isc, beerware, publicDomain) maintained by Michael Weiss - lvm2-2.03.22 (gpl2, bsd2, lgpl21) maintained by Michael Raskin, Andreas Schrägle, Janne Heß - lz4-1.9.4 (bsd2, gpl2Plus) maintained by nobody - glibc-2.38-27 (lgpl2Plus) maintained by Eelco Dolstra, Maximilian Bosch, Connor Baker - libdaemon-0.14 (lgpl2Plus) maintained by nobody - elfutils-0.190 (gpl2Only, lgpl3Plus, gpl3Plus) maintained by Eelco Dolstra, Ryan Burns - libwebp-1.3.2 (bsd3) maintained by Andreas Schrägle - libXi-1.8.1 (no license) maintained by nobody - gobject-introspection-1.78.1 (gpl2, lgpl2) maintained by Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey, Jason O'Conal, Artturi N - json-glib-1.8.0 (lgpl21Plus) maintained by Bobby Rong, Tor Hedin Brønner, Jan Tojnar, Daniel Șerbănescu, Maxine Aubrey - xz-5.4.5 (gpl2Plus, lgpl21Plus) maintained by Sander van der Burg - tcb-1.2 (bsd3) maintained by Yurii Izorkin - pcre2-10.42 (bsd3) maintained by Thomas Tuegel - kexec-tools-2.0.26 (gpl2) maintained by nobody - kmod-31 (lgpl21Plus, gpl2Plus) maintained by Artturi N - libunwind-1.6.2 (mit) maintained by Orivej Desh - perl-5.38.2 (artistic1) maintained by Eelco Dolstra - libseccomp-2.5.5 (lgpl21Only) maintained by Austin Seipp - perl5.38.2-Encode-Locale-1.05 (artistic1, gpl1Plus) maintained by nobody - perl5.38.2-Test-RequiresInternet-0.05 (artistic1, gpl1Plus) maintained by nobody - ncurses-6.4 (mit) maintained by nobody - zstd-1.5.5 (bsd3) maintained by Orivej Desh - curl-8.4.0 (curl) maintained by Jason O'Conal - perl5.38.2-HTTP-Negotiate-6.01 (artistic1, gpl1Plus) maintained by nobody - perl5.38.2-libwww-perl-6.72 (artistic1, gpl1Plus) maintained by nobody - systemd-254.6 (lgpl21Plus) maintained by Florian Klink, Finn Behrens - popt-1.19 (mit) maintained by Alyssa Ross - kmod-31 (lgpl21Plus, gpl2Plus) maintained by Artturi N - libXinerama-1.1.5 (no license) maintained by nobody - libgcrypt-1.10.3 (lgpl2Plus) maintained by Rahul Gopinath - acl-2.3.1 (gpl2Plus) maintained by nobody - libtasn1-4.19.0 (lgpl2Plus) maintained by nobody - perl5.38.2-HTML-Tagset-3.20 (artistic1, gpl1Plus) maintained by nobody - pcsclite-2.0.1 (bsd3) maintained by Anthony Roussel - libtiff-4.6.0 (libtiff) maintained by nobody - bzip2-1.0.8 (bsdOriginal) maintained by Jörg Thalheim - libbsd-unstable-2023-04-29 (beerware, bsd2, bsd3, bsdOriginal, isc, mit) maintained by Matthew Bauer - libkrb5-1.21.2 (mit) maintained by nobody - iso-codes-4.15.0 (lgpl21) maintained by nobody - fontconfig-2.14.2 (bsd2) maintained by Jan Tojnar - gzip-1.13 (gpl3Plus) maintained by nobody - linux-pam-1.5.2 (bsd3) maintained by nobody - libjpeg-turbo-2.1.5.1 (ijg) maintained by Vladimír Čunát, Cole Mickens, Kevin Amado - perl5.38.2-URI-5.21 (artistic1, gpl1Plus) maintained by nobody - dav1d-1.2.1 (bsd2) maintained by Michael Weiss - perl5.38.2-LWP-MediaTypes-6.04 (artistic1, gpl1Plus) maintained by nobody - libXau-1.0.11 (no license) maintained by nobody ``` ## Nix profiles ### Switch to previous system profile https://tldr.inbrowser.app/pages/linux/nixos-rebuild ```shell sudo nixos-rebuild switch --rollback boot sudo reboot ``` ### List system profiles ```shell sudo nix-env --list-generations --profile /nix/var/nix/profiles/system ``` ```console ... 282 2024-11-10 12:53:25 283 2024-11-11 10:45:46 (current) ``` ```shell ls -l /nix/var/nix/profiles/ ``` ```console lrwxrwxrwx 1 root root 43 Dez 26 2023 default -> /nix/var/nix/profiles/per-user/root/profile drwxr-xr-x 1 root root 16 Aug 15 2023 per-user lrwxrwxrwx 1 root root 15 Nov 11 10:45 system -> system-283-link lrwxrwxrwx 1 root root 77 Nov 10 12:53 system-282-link -> /nix/store/jb5krdbbylwwgvxiadiv6fxja2zgc4h3-nixos-system-yodaTab-24.05pre-git lrwxrwxrwx 1 root root 77 Nov 11 10:45 system-283-link -> /nix/store/jf7ml8jzxrmg9djhfr8szq2f19hxysn5-nixos-system-yodaTab-24.05pre-git ``` The currently running system. This is the currently active generation. By comparing the store path with the above output, we see that it matches generation 429. ```shell ls -l /run/current-system ``` ```console lrwxrwxrwx 1 root root 77 Nov 11 10:46 /run/current-system -> /nix/store/jf7ml8jzxrmg9djhfr8szq2f19hxysn5-nixos-system-yodaTab-24.05pre-git ``` ### Deleting generations - Keep most recent X system profiles https://nix.dev/manual/nix/2.18/command-ref/nix-env/delete-generations > Periodically deleting old generations is important to make garbage collection effective. The is because profiles are also garbage collection roots. A NixOS config example is given in [nix-gc.nix](modules/nix-gc.nix). ```shell sudo nix-env --delete-generations +7 --profile /nix/var/nix/profiles/system ``` After deleting some generations, it is still necessary to collect garbage in order to free up your system. See below. ### Garbage collection - Delete unreachable store objects https://nix.dev/manual/nix/2.18/command-ref/nix-collect-garbage > `nix-collect-garbage` deletes all unreachable store objects in the Nix store to clean up your system. * https://nixos.org/manual/nix/stable/package-management/garbage-collection.html * https://discourse.nixos.org/t/why-doesnt-nix-collect-garbage-remove-old-generations-from-efi-menu/17592/4 First delete unreachable store objects: ```shell # Delete unreachable store objects sudo nix-collect-garbage # Deletes all except the currently active generation prior to deleting unreachable store objects #sudo nix-collect-garbage --delete-old # Deletes all generations older than 14d prior to deleting unreachable store objects #sudo nix-collect-garbage --delete-older-than 14d ``` Then remove leftover EFI entries of deleted generations: ```shell sudo /run/current-system/bin/switch-to-configuration boot ``` ### why-depends: Why is a package/dependency installed Usage of `why-depends`: https://github.com/tldr-pages/tldr/blob/f952fc71c2587fa13207aee278eb8795af913438/pages/common/nix3-why-depends.md Show why the currently running NixOS system requires a certain store path. - Example: Why is one store path required. ```shell nix --extra-experimental-features flakes --extra-experimental-features nix-command why-depends /run/current-system /nix/store/mzx8sgjkw7x2p9alq6cgz0vcdzaqz188-openssh-9.6p1 ``` ```console /nix/store/k7c7576sz868gzjci1z6l6nzmdnpd6xr-nixos-system-yodaTux-23.11pre-git └───/nix/store/b9mbk3jvazblxfma5p2yvc9xlmvrqxx7-etc └───/nix/store/mzx8sgjkw7x2p9alq6cgz0vcdzaqz188-openssh-9.6p1 ``` - Example: Why are any of the `ffmpeg-headless` store paths currently required? ```shell for i in /nix/store/*ffmpeg-headless-*; do env PAGER=cat nix --extra-experimental-features flakes --extra-experimental-features nix-command why-depends /run/current-system "$i" 2>/dev/null done; ``` ```console /nix/store/k7c7576sz868gzjci1z6l6nzmdnpd6xr-nixos-system-yodaTux-23.11pre-git └───/nix/store/b9mbk3jvazblxfma5p2yvc9xlmvrqxx7-etc └───/nix/store/snva91gl7hlm0fsf5mg5k0prv8mwnhcv-pipewire-1.0.1 └───/nix/store/jqlvhb8jfz43vkl14wsm88h6csmx8aia-ffmpeg-headless-6.0-lib /nix/store/k7c7576sz868gzjci1z6l6nzmdnpd6xr-nixos-system-yodaTux-23.11pre-git └───/nix/store/b9mbk3jvazblxfma5p2yvc9xlmvrqxx7-etc └───/nix/store/nhypp8f5h0xv9ar9wzbp12hzyg1vah1a-user-environment └───/nix/store/0df15gc1a4s98n961vdd2j1pkkckn901-resources-1.3.0 └───/nix/store/f61vlw8ampb5nh25kvs9p7rbi3cclcr4-gtk4-4.12.5 └───/nix/store/5r52pj0fj3b06r0qgglasfmqmsfh315q-gst-plugins-bad-1.22.9 └───/nix/store/dsdfn1k9hnxzdwvzirx2smfinziqc8bz-openal-soft-1.23.1 └───/nix/store/ci4z4i38d7akpi5fqcdr2nvd1sr30l3i-pipewire-1.0.3 └───/nix/store/rpnsg493xz3fjhfrlc3ifz2ln65kmi8q-ffmpeg-headless-6.1-lib ... ``` ### Compare two system profiles Get latest system profile. This is the profile (usually) being active after booting the system: ```shell ls -1 /nix/var/nix/profiles/ | sort -t'-' -n -k2 | tail -n 1 #=> 120 ``` Compare current with previous profile: ```shell # https://discourse.nixos.org/t/how-to-know-what-nixpkgs-changes-affect-me/18142/6 prev="$(ls -r /nix/var/nix/profiles/ | grep -E 'system\-' | sed -n '2 p')" curr=/nix/var/nix/profiles/system nix --extra-experimental-features nix-command store diff-closures /nix/var/nix/profiles/"${prev}" "${curr}" ``` ```shell # https://stackoverflow.com/a/36641298 prev="$(ls -1 /nix/var/nix/profiles/ | sort -t'-' -n -k2 | tail -n 2 | head -n 1)" curr="$(ls -1 /nix/var/nix/profiles/ | sort -t'-' -n -k2 | tail -n 1)" nix --extra-experimental-features nix-command store diff-closures /nix/var/nix/profiles/"${prev}" /nix/var/nix/profiles/"${curr}" ``` Compare two arbitrary system profiles: ```shell nix --extra-experimental-features nix-command store diff-closures /nix/var/nix/profiles/system-110-link /nix/var/nix/profiles/system-116-link ``` ``` cpupower: 6.1.47 → 6.1.51 element-desktop: 1.11.38 → 1.11.40, +2218.9 KiB element-web: 1.11.38 → 1.11.40, -73.1 KiB exempi: 2.6.3 → 2.6.4 firefox: 116.0.3 → 117.0 firefox-unwrapped: 116.0.3 → 117.0, -292.6 KiB gnome-shell-extension-openweather: ∅ → 121, +590.5 KiB hm_fontconfigconf.d10hmfonts.conf: ∅ → ε initrd: ∅ → ε initrd-linux: 6.1.47 → 6.1.51 libcap: 2.68 → 2.69 linux: 6.1.47, 6.1.47-modules → 6.1.51, 6.1.51-modules, -11.8 KiB meld: ∅ → 3.22.0, +3858.5 KiB net-snmp: 5.9.3 → 5.9.4 nixos-system-yodaTab: 23.05.3085.2ab91c8d65c0 → 23.05.3242.da5adce0ffaf openjdk: +19.5 KiB python3.10-pygobject: +27.0 KiB stage: ∅ → 1-init.sh, +29.5 KiB tor-browser-bundle-bin: 12.5.2 → 12.5.3, +18.1 KiB user: +2885.0 KiB ``` ## NixOS configuration debugging * https://nixos.wiki/wiki/Nix_command/repl Evaluating parts of the configuration. First, start `nix repl`: ```shell nix repl --file '' -I nixos-config=hosts/$(hostname)/configuration.nix ``` Example: `config.home-manager` ```shell config.home-manager. # Press `TAB` #=> config.home-manager.backupFileExtension config.home-manager.useUserPackages #=> config.home-manager.extraSpecialArgs config.home-manager.users #=> config.home-manager.sharedModules config.home-manager.verbose #=> config.home-manager.useGlobalPkgs ``` Example: The `home` variable: ```shell config.home-manager.users.yoda.home ``` Example: The value of one config option ```shell # The following option is set to `"${config.xdg.dataHome}/.histfile";` # where `config` is the Home Manager configuration. config.home-manager.users.yoda.programs.zsh.history.path #=> "/home/yoda/.local/share/.histfile" ``` ## Show Nix configuration * https://nixos.org/manual/nix/stable/command-ref/new-cli/nix3-show-config.html ```shell nix --extra-experimental-features nix-command show-config ``` ## Evaluate NixOS configuration to JSON See also section "NixOS Configuration Debugging"! * https://discourse.nixos.org/t/can-i-run-nix-instantiate-eval-strict-on-my-configuration-nix/7105/4 This evaluates `configuration.nix` (single module): ```shell NIXPKGS_ALLOW_UNFREE=1 nix-instantiate --strict --json --eval -E ' import ./hosts/yodaTab/configuration.nix { config = {}; pkgs = import {}; lib = import ; } ' > evaluated-config.json ``` Then open `evaluated-config.json`. ## Evaluate expressions in the context of a NixOS configuration managed with Colmena https://colmena.cli.rs/unstable/reference/cli.html#colmena-eval Either specify a file containing the expression or add it as argument with `-E`. ```shell colmena eval -E '{ nodes, lib, pkgs, ... }: nodes.yodaTux.config.networking.hostName' ``` ```shell nix-shell -p jq colmena eval -E '{ nodes, lib, pkgs, ... }: nodes.yodaTux.config.environment.systemPackages' | jq ``` ```shell colmena eval -E '{ nodes, lib, pkgs, ... }: pkgs.linux' #=> "/nix/store/bmyh7a4j9xim7xxc5x1qk1qvlb2y7186-linux-6.6.48" ``` ```shell colmena eval -E '{ nodes, lib, pkgs, ... }: pkgs.linuxPackages.kernel' #=> "/nix/store/bmyh7a4j9xim7xxc5x1qk1qvlb2y7186-linux-6.6.48" colmena eval -E '{ nodes, lib, pkgs, ... }: pkgs.linuxPackages_latest.kernel' #=> "/nix/store/n0csng9aw5nhpll1m5rbvvxkkj2j63px-linux-6.10.7" ``` Lists and strings will be printed. To inspect an attribute set, add `pkgs.lib.attrNames`. ```shell colmena eval -E '{ nodes, lib, pkgs, ... }: pkgs.lib.attrNames nodes.yodaTux.pkgs.rust-bin.stable.latest.default' #=> [...,"type","userHook","version"] ``` ## Evaluate expressions * https://discourse.nixos.org/t/eval-nix-expression-from-the-command-line/8993/6 ```shell nix-instantiate --eval -E 'with import { }; vscode.version' #=> "1.78.2" ``` Shell wrapper: ```shell nix-eval() { nix-instantiate --eval -E "with import {}; ${*}"; } ``` Examples: ```shell nix-eval 'vscode.version' #=> "1.78.2" nix-eval 'lib.forEach [ 1 2 ] (x: toString x)' #=> [ "1" "2" ] nix-eval 'lib.head [1 2]' #=> 1 nix-eval 'lib.head ( lib.forEach [ 1 2 ] (x: toString x) )' #=> "1" nix-eval 'lib.head ( lib.forEach [ {a=1;} {a=2;} ] (x: x.a) )' #=> 1 nix-eval 'lib.attrsets.mergeAttrsList [{a=1;} {b=2;}]' #=> { a = 1; b = 2; } nix-eval '{ a=1; }.b or 2' #=> 2 nix-eval '{ a=false; }.a or true' #=> false nix-eval '{ a=1; }?a' #=> true nix-eval 'with lib.strings; concatMapStrings (x: " -a " + x + " -i 600") ["sda" "sdc"]' #=> " -a sda -i 600 -a sdc -i 600" ``` ## Escape strings * https://nixos.org/manual/nix/stable/language/values Double-quoted strings (e.g. `"foo bar"`): ``` " -> \" \ -> \\ ${ -> \${ ``` Indented strings (e.g. `''foo bar''`): * `${` -> `''${` * `''` -> `'''` URIs can be written without quotes (e.g. `http://example.org/foo.bar`). ## Run AppImages * https://nixos.wiki/wiki/Appimage ```shell # Note how your shell prefix changes. nix-shell -p appimage-run ``` ```shell # Inside the shell, you can run an AppImage: appimage-run ~/Downloads/ubports-installer_0.10.0_linux_x86_64.AppImage ``` See the [binfmt option](https://nixos.org/manual/nixos/stable/options#opt-programs.appimage.binfmt) to e.g. run AppImages of other processor architectures. ## Audio troubleshooting - Realtek ALC898 Audio Codec on ASRock Z77 Extreme 4 TODO: I couldn't get the onboard audio to work. - https://discourse.nixos.org/t/fixing-audio-on-asus-strix-scar-17-g733qs/12687 - https://bbs.archlinux.org/viewtopic.php?id=147242 - https://en.opensuse.org/SDB:Audio_troubleshooting#Script_to_run_to_obtain_detailed_information - https://nixos.wiki/wiki/ALSA#Other_hardware_specific_problems - https://bbs.archlinux.org/viewtopic.php?pid=1452128#p1452128 `aplay -L` ```console null Discard all samples (playback) or generate zero samples (capture) pipewire PipeWire Sound Server default Default ALSA Output (currently PipeWire Media Server) hdmi:CARD=HDMI,DEV=0 HDA ATI HDMI, HDMI 0 * HDMI Audio Output hdmi:CARD=HDMI,DEV=1 HDA ATI HDMI, HDMI 1 HDMI Audio Output hdmi:CARD=HDMI,DEV=2 HDA ATI HDMI, HDMI 2 HDMI Audio Output hdmi:CARD=HDMI,DEV=3 HDA ATI HDMI, HDMI 3 HDMI Audio Output hdmi:CARD=HDMI,DEV=4 HDA ATI HDMI, HDMI 4 HDMI Audio Output hdmi:CARD=HDMI,DEV=5 HDA ATI HDMI, HDMI 5 HDMI Audio Output ``` `cat /proc/asound/cards` ```console 0 [HDMI ]: HDA-Intel - HDA ATI HDMI HDA ATI HDMI at 0xf7b60000 irq 40 ``` `lspci -vnn | grep -A1 -i audio` ```console 00:1b.0 Audio device [0403]: Intel Corporation 7 Series/C216 Chipset Family High Definition Audio Controller [8086:1e20] (rev 04) Subsystem: ASRock Incorporation Z77 Extreme4 motherboard [1849:1898] -- 01:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Tahiti HDMI Audio [Radeon HD 7870 XT / 7950/7970] [1002:aaa0] Subsystem: Advanced Micro Devices, Inc. [AMD/ATI] Tahiti HDMI Audio [Radeon HD 7870 XT / 7950/7970] [1002:aaa0] Flags: bus master, fast devsel, latency 0, IRQ 40 ``` `sudo lspci -vnn` ```console 00:1b.0 Audio device [0403]: Intel Corporation 7 Series/C216 Chipset Family High Definition Audio Controller [8086:1e20] (rev 04) Subsystem: ASRock Incorporation Z77 Extreme4 motherboard [1849:1898] Flags: fast devsel, IRQ 22 Memory at f7c10000 (64-bit, non-prefetchable) [size=16K] Capabilities: [50] Power Management version 2 Capabilities: [60] MSI: Enable- Count=1/1 Maskable- 64bit+ Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 00 Capabilities: [100] Virtual Channel Capabilities: [130] Root Complex Link Kernel modules: snd_hda_intel ``` ## Graphic drivers Usually most of this should work out of the box on NixOS. Vulkan: - Verification: - If `vulkaninfo` returns information about your GPU, Vulkan is working. https://wiki.archlinux.org/title/Vulkan#Verification - `nix-shell -p vulkan-tools --run vulkaninfo` - Run `vkcube` (X11) or `vkcube-wayland` (Wayland). It should view a spinning 3D cube and output e.g. `Selected GPU 0: AMD Radeon Graphics (RADV RENOIR)` - `nix-shell -p vulkan-tools --run vkcube-wayland` OpenGL: - Verification: https://wiki.archlinux.org/title/OpenGL#Verification - `eglinfo -B` should not return `eglInitialize failed` - `nix-shell -p glxinfo --run 'eglinfo -B'` - `eglgears_x11` and `eglgears_wayland` -> ![eglgears.png](assets/doc/eglgears.png) - `nix-shell -p mesa-demos --run eglgears_wayland` Video acceleration: - VA-API - Video Acceleration API (VA-API). Provides both hardware accelerated video encoding and decoding. - Verifying: `vainfo` -> E.g. `Driver version: Mesa Gallium driver 23.1.9 for AMD Radeon Graphics`. https://wiki.archlinux.org/title/Hardware_video_acceleration#Verifying_VA-API - `nix-shell -p libva-utils --run vainfo` - Driver comparison chart. https://wiki.archlinux.org/title/Hardware_video_acceleration#VA-API_drivers - With `libva-mesa-driver` on "Radeon RX 7900 and higher/newer" a codec for encoding AV1 8 and 10 bit is available. - VDPAU - Video Decode and Presentation API for Unix (VDPAU). Offload portions of the video decoding process and video post-processing to the GPU video-hardware. - Verifying: `vdpauinfo`. https://wiki.archlinux.org/title/Hardware_video_acceleration#Verifying_VDPAU - `nix-shell -p vdpauinfo --run vdpauinfo` GPGPU (General-purpose computing on graphics processing units): - OpenCL - Verification using `clinfo` - `nix-shell -p clinfo --run 'clinfo -l'` - Should produce non-empty output, e.g. `Platform #0: AMD Accelerated Parallel Processing` - `nix-shell -p clinfo --run clinfo` - This output is more verbose. - `Number of platforms` should be >= 1 Verify video driver in use: - `lspci -k | grep -EA3 'VGA|3D|Display'`. Example: `Kernel driver in use: amdgpu` - `nix-shell -p pciutils --run 'lspci -k | grep -EA3 "VGA|3D|Display"'` Verification in general: - Encode a video or play a game and watch AMD GPU usage with `radeontop`. - `nix-shell -p radeontop --run radeontop` Configuration example to disable integrated GUP: See [./hosts/yodaGaming/configuration.nix](./hosts/yodaGaming/configuration.nix) Configuration example for an AMD GPU (https://github.com/tolgaerok/nixos-kde/blob/main/core/gpu/amd/default.nix): See [./modules/gpu-amd.nix](./modules/gpu-amd.nix) ## XDG mimes, desktop files Desktop files: - `/run/current-system/sw/share/applications` - `/etc/profiles/per-user/yoda/share/applications/` Both above sub-paths are part of the `XDG_DATA_DIRS` variable: - `echo $XDG_DATA_DIRS | grep /run/current-system/sw/share` - `echo $XDG_DATA_DIRS | grep /etc/profiles/per-user/yoda/share` List default apps and the associated handlers: ```shell handlr list ``` ```console ┌────────────────────────────────┬─────────────────────────────────────────┐ │ application/octet-stream │ thunderbird.desktop │ │ ... │ │ │ x-scheme-handler/sgnl │ signal-desktop.desktop │ └────────────────────────────────┴─────────────────────────────────────────┘ ``` Set default handler for mime/extension: ```shell handlr set text/html re.sonny.Junction.desktop ``` Open any URI with `handlr`: ```shell handlr open https://wikipedia.org ``` Open any URI with `gio`, part of `glib`: ```shell gio open https://wikipedia.org ``` - Note: `gio open` does not follow the XDG spec. https://discourse.nixos.org/t/configure-how-xdg-open-opens-html-files/6419/23 Further examples: ```shell xdg-settings get default-web-browser #=> re.sonny.Junction.desktop xdg-mime query default x-scheme-handler/http and x-scheme-handler/https #=> re.sonny.Junction.desktop xdg-mime query default text/html #=> firefox.desktop ``` ## Additional resources * Simple NixOS flake template for NixOS with HomeManager. https://github.com/Misterio77/nix-starter-configs#readme * NixOS guide (development environment, gaming, etc). https://github.com/mikeroyal/NixOS-Guide#table-of-contents * nix function cheatsheet: https://nix-cheatsheet.pixie.homes/ * Documenting the Journey of Learning and Mastering Nix. https://ianthehenry.com/posts/how-to-learn-nix/ * Nix language basics. https://nix.dev/tutorials/nix-language.html * Nix data types. https://nixos.org/manual/nix/stable/language/values * MkIfElse. https://discourse.nixos.org/t/mkif-vs-if-then/28521/4 * Nix language basics - a one-pager. https://github.com/tazjin/nix-1p#nix---a-one-pager ### Nix Pills * https://nixos.org/guides/nix-pills/pr01 It provides a tutorial introduction into the Nix package manager and Nixpkgs package collection, in the form of short chapters called 'pills'. ### Papers Papers about Nix: * The Purely Functional Software Deployment Model (2006). http://nixos.org/~eelco/pubs/phd-thesis.pdf, https://edolstra.github.io/pubs/phd-thesis.pdf, https://github.com/edolstra/edolstra.github.io/blob/master/pubs/phd-thesis.pdf * May 2023: Some insights from the thesis in short form. https://jonathanlorimer.dev/posts/nix-thesis.html * NixOS: A Purely Functional Linux Distribution (2008): https://github.com/edolstra/edolstra.github.io/blob/master/pubs/nixos-icfp2008-final.pdf, https://github.com/edolstra/edolstra.github.io/blob/master/pubs/nixos-jfp-final.pdf * Nix: A Safe and Policy-Free System for Software Deployment (2004): https://edolstra.github.io/pubs/nspfssd-lisa2004-final.pdf * Prins, P., Suresh, J. and Dolstra, E., "Nix fixes dependency hell on all Linux distributions," [Archived](https://web.archive.org/web/20081226010942/http://www.linux.com/feature/155922) December 26, 2008, at the Wayback Machine linux.com, December 22, 2008