chore(libmain): license it under LGPL-2.1-only

Progress towards REUSE compliance.

Change-Id: I2991234cfd193773a377d2f1735b9974918b8138
Signed-off-by: Raito Bezarius <raito@lix.systems>

.clang-format

@@ -0,0 +1,50 @@
+---
+BasedOnStyle: LLVM
+AccessModifierOffset: -4
+AlignAfterOpenBracket: BlockIndent
+AlignEscapedNewlines: Left
+AlignOperands: DontAlign
+AllowShortBlocksOnASingleLine: Always
+AllowShortFunctionsOnASingleLine: Empty
+AllowShortIfStatementsOnASingleLine: WithoutElse
+AlwaysBreakBeforeMultilineStrings: true
+AlwaysBreakTemplateDeclarations: Yes
+BinPackArguments: false
+BinPackParameters: false
+BitFieldColonSpacing: None
+BraceWrapping:
+  AfterCaseLabel: false
+  AfterClass: true
+  AfterControlStatement: MultiLine
+  AfterEnum: false
+  AfterFunction: true
+  AfterNamespace: false
+  AfterObjCDeclaration: false
+  AfterStruct: true
+  AfterUnion: true
+  AfterExternBlock: false
+  BeforeCatch: false
+  BeforeElse: false
+  BeforeLambdaBody: false
+  BeforeWhile: false
+  IndentBraces: false
+  SplitEmptyFunction: true
+  SplitEmptyRecord: false
+  SplitEmptyNamespace: true
+BreakAfterAttributes: Always
+BreakBeforeBinaryOperators: NonAssignment
+BreakBeforeBraces: Custom
+BreakConstructorInitializers: BeforeComma
+ColumnLimit: 100
+EmptyLineAfterAccessModifier: Leave
+EmptyLineBeforeAccessModifier: Leave
+FixNamespaceComments: false
+IndentWidth: 4
+InsertBraces: true
+InsertTrailingCommas: Wrapped
+LambdaBodyIndentation: Signature
+PackConstructorInitializers: CurrentLine
+PointerAlignment: Middle
+SortIncludes: Never
+SpaceAfterCStyleCast: true
+SpaceAfterTemplateKeyword: false

.clang-tidy

@@ -0,0 +1,18 @@
+UseColor: true
+Checks:
+  - -*
+  - bugprone-*
+    # too many warnings
+  - -bugprone-assignment-in-if-condition
+    # too many warnings
+  - -bugprone-narrowing-conversions
+    # kind of nonsense
+  - -bugprone-easily-swappable-parameters
+    # too many warnings for now
+  - -bugprone-implicit-widening-of-multiplication-result
+    # Lix's exception handling is Questionable
+  - -bugprone-empty-catch
+    # many warnings
+  - -bugprone-unchecked-optional-access
+    # many warnings, seems like a questionable lint
+  - -bugprone-branch-clone

.dir-locals.el

@@ -0,0 +1,18 @@
+((c++-mode . (
+  (c-file-style . "k&r")
+  (c-basic-offset . 4)
+  (c-block-comment-prefix . "  ")
+  (indent-tabs-mode . nil)
+  (tab-width . 4)
+  (show-trailing-whitespace . t)
+  (indicate-empty-lines . t)
+  (eval . (c-set-offset 'innamespace 0))
+  (eval . (c-set-offset 'defun-open 0))
+  (eval . (c-set-offset 'inline-open 0))
+  (eval . (c-set-offset 'arglist-intro '+))
+  (eval . (c-set-offset 'arglist-cont 0))
+  (eval . (c-set-offset 'arglist-cont-nonempty '+))
+  (eval . (c-set-offset 'substatement-open 0))
+  (eval . (c-set-offset 'access-label '-))
+  (eval . (c-set-offset 'inlambda 0))
+  )))

.editorconfig

@@ -0,0 +1,31 @@
+# EditorConfig configuration for nix
+# http://EditorConfig.org
+
+# Top-most EditorConfig file
+root = true
+
+# Unix-style newlines with a newline ending every file, utf-8 charset
+[*]
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+charset = utf-8
+
+# Match nix files, set indent to spaces with width of two
+[*.nix]
+indent_style = space
+indent_size = 2
+
+# Match c++/shell/perl, set indent to spaces with width of four
+[*.{hpp,cc,hh,sh,pl}]
+indent_style = space
+indent_size = 4
+
+# Match diffs, avoid to trim trailing whitespace
+[*.{diff,patch}]
+trim_trailing_whitespace = false
+
+[*.md]
+indent_style = space
+indent_size = 2
+max_line_length = 0

.envrc

@@ -0,0 +1,5 @@
+# shellcheck shell=bash
+source_env_if_exists .envrc.local
+# Use native-clangStdenvPackages to get clangd by default.
+use flake ".#${LIX_SHELL_VARIANT:-native-clangStdenvPackages}" "${LIX_SHELL_EXTRA_ARGS[@]}"
+export GTEST_BRIEF=1

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,32 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: ''
+labels: bug
+assignees: ''
+
+---
+
+## Describe the bug
+
+A clear and concise description of what the bug is.
+
+If you have a problem with a specific package or NixOS,
+you probably want to file an issue at https://github.com/NixOS/nixpkgs/issues.
+
+## Steps To Reproduce
+
+1. Go to '...'
+2. Click on '....'
+3. Scroll down to '....'
+4. See error
+
+## Expected behavior
+
+A clear and concise description of what you expected to happen.
+
+## `nix --version` output
+
+## Additional context
+
+Add any other context about the problem here.

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,24 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: feature
+assignees: ''
+
+---
+
+## Is your feature request related to a problem? Please describe.
+
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+## Describe the solution you'd like
+
+A clear and concise description of what you want to happen.
+
+## Describe alternatives you've considered
+
+A clear and concise description of any alternative solutions or features you've considered.
+
+## Additional context
+
+Add any other context or screenshots about the feature request here.

.github/ISSUE_TEMPLATE/installer.md

@@ -0,0 +1,32 @@
+---
+name: Installer issue
+about: Report problems with installation
+title: ''
+labels: installer
+assignees: ''
+
+---
+
+## Platform
+
+<!-- select the platform on which you tried to install Lix -->
+
+- [ ] Linux: <!-- state your distribution, e.g. Arch Linux, Ubuntu, ... -->
+- [ ] macOS
+- [ ] WSL
+
+## Additional information
+
+<!-- state special circumstances on your system or additional steps you have taken prior to installation -->
+
+## Output
+
+<details><summary>Output</summary>
+
+```log
+
+<!-- paste console output here and remove this comment -->
+
+```
+
+</details>

.github/ISSUE_TEMPLATE/missing_documentation.md

@@ -0,0 +1,28 @@
+---
+name: Missing or incorrect documentation
+about: Help us improve the reference manual
+title: ''
+labels: documentation
+assignees: ''
+
+---
+
+## Problem
+
+<!-- describe your problem -->
+
+## Proposal
+
+<!-- propose a solution -->
+
+## Checklist
+
+<!-- make sure this issue is not redundant or obsolete -->
+
+- [ ] checked [latest Lix manual] \([source]\)
+- [ ] checked [documentation issues] and [recent documentation changes] for possible duplicates
+
+[latest Nix manual]: https://docs.lix.systems/manual/lix/nightly
+[source]: https://git.lix.systems/lix-project/lix/src/main/doc/manual/src
+[documentation issues]: https://git.lix.systems/lix-project/lix/issues?labels=151&state=all
+[recent documentation changes]: https://gerrit.lix.systems/q/p:lix+path:%22%5Edoc/manual/.*%22

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,11 @@
+# Motivation
+<!-- Briefly explain what the change is about and why it is desirable. -->
+
+# Context
+<!-- Provide context. Reference open issues if available. -->
+
+<!-- Non-trivial change: Briefly outline the implementation strategy. -->
+
+<!-- Invasive change: Discuss alternative designs or approaches you considered. -->
+
+<!-- Large change: Provide instructions to reviewers how to read the diff. -->

.gitignore

@@ -0,0 +1,31 @@
+outputs/
+
+# GNU Global
+GPATH
+GRTAGS
+GSYMS
+GTAGS
+
+# ccls
+/.ccls-cache
+
+result
+result-*
+
+.vscode/
+.direnv/
+
+# clangd and possibly more
+.cache/
+
+# Mac OS
+.DS_Store
+
+# ClangBuildAnalyzer output, see maintainers/buildtime_report.sh
+buildtime.bin
+
+.envrc.local
+# We generate this with a Nix shell hook
+/.pre-commit-config.yaml
+/.nocontribmsg
+/release

.this-is-lix

@@ -0,0 +1 @@
+This is a file used by the dev shell shellHook in package.nix to check that this is actually a Lix repo before installing git hooks. Its contents have no meaning.

CONTRIBUTING.md

@@ -0,0 +1,53 @@
+# Contributing to Lix
+
+Welcome and thank you for considering contributing to Lix! We're currently in a soft release phase, and your support means a lot to us.
+
+To ensure a smooth and effective contribution process, here is a summary of our guidelines:
+
+## Getting help?
+
+If you have any question regarding getting started or reporting bugs, feel free
+to reach out to us.
+
+On Matrix, we have a space at `#space:lix.systems`, composed of:
+
+- [`#discuss:lix.systems`](https://matrix.to/#/#discuss:lix.systems) for discussions on Lix.
+- [`#dev:lix.systems`](https://matrix.to/#/#dev:lix.systems) for the development channel on Lix.
+
+## Report a bug
+
+- Check if your bug has already been reported in the [issue tracker](https://git.lix.systems/lix-project/lix/issues).
+- If you can't find the bug or feature, please open a new issue.
+
+We maintain a copy of the upstream Nix bugs. Their organisation can be read about [here](https://wiki.lix.systems/books/lix-contributors/page/bug-tracker-organisation).
+
+## Report a security vulnerability
+
+For security vulnerabilities, reach out by email at `security at lix dot systems`.
+
+## Making changes to Lix
+
+Before diving into making changes, we want to engage with you and your ideas.
+
+We have a few policies in effect; please take the time to familiarize yourself:
+
+- [Style guide on code](https://wiki.lix.systems/books/lix-contributors/page/code)
+- [Freeze policy and recommended contributions](https://wiki.lix.systems/books/lix-contributors/page/freezes-and-recommended-contributions)
+
+To avoid duplication of effort, it may be a good idea to check out the list of
+[pending pull requests](https://gerrit.lix.systems/q/status:open+-is:wip) (or "change lists", as Gerrit calls them). Once you have
+an idea of what you might want to do, we recommend dropping a message on our
+Matrix to ensure your contribution fits with our current schedule and plans
+
+When you're ready and your changes are ready to go:
+
+- Submit your code.
+  - Submitting a GitHub PR [on our mirror](https://github.com/lix-project/lix) is totally ok if that's easier for you and your change is relatively small (300 lines or so).
+
+    We may ask you to resubmit it as a Gerrit CL if it is necessary for the change you're making.
+  - Our primary code review system is [our Gerrit instance](https://gerrit.lix.systems), where you can open a change list (CL).
+    If you're new to Gerrit, check out [our wiki page about Gerrit](https://wiki.lix.systems/books/lix-contributors/page/gerrit).
+- Make sure to link any related issues.
+- If needed, indicate that the change is 'work in progress'.
+
+You can obtain an account on our platforms by clicking "Sign In with GitHub" on the sign-in page.

COPYING

@@ -0,0 +1,502 @@
+		  GNU LESSER GENERAL PUBLIC LICENSE
+		       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+ 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL.  It also counts
+ as the successor of the GNU Library Public License, version 2, hence
+ the version number 2.1.]
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+Licenses are intended to guarantee your freedom to share and change
+free software--to make sure the software is free for all its users.
+
+  This license, the Lesser General Public License, applies to some
+specially designated software packages--typically libraries--of the
+Free Software Foundation and other authors who decide to use it.  You
+can use it too, but we suggest you first think carefully about whether
+this license or the ordinary General Public License is the better
+strategy to use in any particular case, based on the explanations below.
+
+  When we speak of free software, we are referring to freedom of use,
+not price.  Our General Public Licenses are designed to make sure that
+you have the freedom to distribute copies of free software (and charge
+for this service if you wish); that you receive source code or can get
+it if you want it; that you can change the software and use pieces of
+it in new free programs; and that you are informed that you can do
+these things.
+
+  To protect your rights, we need to make restrictions that forbid
+distributors to deny you these rights or to ask you to surrender these
+rights.  These restrictions translate to certain responsibilities for
+you if you distribute copies of the library or if you modify it.
+
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+it.  And you must show them these terms so they know their rights.
+
+  We protect your rights with a two-step method: (1) we copyright the
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+  Most GNU software, including some libraries, is covered by the
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+General Public License, applies to certain designated libraries, and
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+  We call this license the "Lesser" General Public License because it
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+
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+possible use to the public, we recommend making it free software that
+everyone can redistribute and change.  You can do so by permitting
+redistribution under these terms (or, alternatively, under the terms of the
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+
+  To apply these terms, attach the following notices to the library.  It is
+safest to attach them to the start of each source file to most effectively
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+
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+    Copyright (C) <year>  <name of author>
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
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+
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+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the library, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
+  library `Frob' (a library for tweaking knobs) written by James Random Hacker.
+
+  <signature of Ty Coon>, 1 April 1990
+  Ty Coon, President of Vice
+
+That's all there is to it!

README.md

@@ -0,0 +1,29 @@
+# Lix
+
+**Lix** is an implementation of **Nix**, a powerful package management system for Linux and other Unix systems that makes package management reliable and reproducible.
+
+Read more about us at https://lix.systems.
+
+## Installation
+
+On Linux and macOS the easiest way to install Lix is to run the following shell command
+(as a user other than root):
+
+```console
+$ curl -sSf -L https://install.lix.systems/lix | sh -s -- install
+```
+
+For systems that **already have a Nix implementation installed**, such as NixOS systems, read our [install page](https://lix.systems/install)
+
+## Building And Developing
+
+See our [Hacking guide](https://git.lix.systems/lix-project/lix/src/branch/main/doc/manual/src/contributing/hacking.md) in our manual for instruction on how to to set up a development environment and build Lix from source.
+
+## Additional Resources
+
+- [Our wiki](https://wiki.lix.systems)
+- [Matrix - #space:lix.systems](https://matrix.to/#/#space:lix.systems)
+
+## License
+
+Lix is released under the [LGPL v2.1](./COPYING).

bench/.gitignore

@@ -0,0 +1,3 @@
+bench-*.json
+bench-*.md
+nixpkgs

bench/README.md

@@ -0,0 +1,91 @@
+# Benchmarking scripts for Lix
+
+These are very much WIP, and have a few clumsy assumptions that we would
+somewhat rather be fixed, but we have committed them to let others be able to
+do benchmarking in the mean time.
+
+## Benchmarking procedure
+
+Build some Lixes you want to compare, by whichever means you wish.
+
+Get a computer that is not busy and *strongly preferably* is bare-metal or at
+least not a cloud VM (e.g. go make coffee when running benchmarks).
+
+From the root of a Lix checkout, run `./bench/bench.sh resultlink-one
+resultlink-two`, where `resultlink-one` and `resultlink-two` are the result
+links from the builds you want to test (they can be any directory with bin/nix
+in it, however).
+
+To get the summary again, run `./bench/summarize.jq bench/bench-*.json`.
+
+## Example results
+
+(vim tip: `:r !bench/summarize.jq bench/bench-*.json` to dump it directly into
+your editor)
+
+```
+result-asserts/bin/nix --extra-experimental-features 'nix-command flakes' search --no-eval-cache github:nixos/nixpkgs/e1fa12d4f6
+c6fe19ccb59cac54b5b3f25e160870 hello
+  mean:     15.993s ± 0.081s
+            user: 13.321s | system: 1.865s
+  median:   15.994s
+  range:    15.829s ... 16.096s
+  relative: 1
+result/bin/nix --extra-experimental-features 'nix-command flakes' search --no-eval-cache github:nixos/nixpkgs/e1fa12d4f6c6fe19cc
+b59cac54b5b3f25e160870 hello
+  mean:     15.897s ± 0.075s
+            user: 13.248s | system: 1.843s
+  median:   15.88s
+  range:    15.807s ... 16.047s
+  relative: 0.994
+
+---
+
+result/bin/nix --extra-experimental-features 'nix-command flakes' eval -f bench/nixpkgs/pkgs/development/haskell-modules/hackage-packages.nix
+  mean:     0.4s ± 0.024s
+            user: 0.335s | system: 0.046s
+  median:   0.386s
+  range:    0.379s ... 0.43s
+  relative: 1
+
+result-asserts/bin/nix --extra-experimental-features 'nix-command flakes' eval -f bench/nixpkgs/pkgs/development/haskell-modules/hackage-packages.nix
+  mean:     0.404s ± 0.024s
+            user: 0.338s | system: 0.046s
+  median:   0.386s
+  range:    0.384s ... 0.436s
+  relative: 1.008
+
+---
+
+result-asserts/bin/nix --extra-experimental-features 'nix-command flakes' eval --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'
+  mean:     5.838s ± 0.023s
+            user: 5.083s | system: 0.464s
+  median:   5.845s
+  range:    5.799s ... 5.867s
+  relative: 1
+
+result/bin/nix --extra-experimental-features 'nix-command flakes' eval --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'
+  mean:     5.788s ± 0.044s
+            user: 5.056s | system: 0.439s
+  median:   5.79s
+  range:    5.715s ... 5.876s
+  relative: 0.991
+
+---
+
+GC_INITIAL_HEAP_SIZE=10g result-asserts/bin/nix eval --extra-experimental-features 'nix-command flakes' --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'
+  mean:     4.147s ± 0.021s
+            user: 3.457s | system: 0.487s
+  median:   4.147s
+  range:    4.123s ... 4.195s
+  relative: 1
+
+GC_INITIAL_HEAP_SIZE=10g result/bin/nix eval --extra-experimental-features 'nix-command flakes' --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'
+  mean:     4.149s ± 0.027s
+            user: 3.483s | system: 0.456s
+  median:   4.142s
+  range:    4.126s ... 4.215s
+  relative: 1
+
+---
+```

bench/bench.sh

@@ -0,0 +1,62 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+shopt -s inherit_errexit
+
+scriptdir=$(cd "$(dirname -- "$0")" ; pwd -P)
+cd "$scriptdir/.."
+
+if [[ $# -lt 2 ]]; then
+    # FIXME(jade): it is a reasonable use case to want to run a benchmark run
+    # on just one build. However, since we are using hyperfine in comparison
+    # mode, we would have to combine the JSON ourselves to support that, which
+    # would probably be better done by writing a benchmarking script in
+    # not-bash.
+    echo "Fewer than two result dirs given, nothing to compare!" >&2
+    echo "Pass some directories (with names indicating which alternative they are) with bin/nix in them" >&2
+    echo "Usage: ./bench/bench.sh result-1 result-2 [result-3...]" >&2
+    exit 1
+fi
+
+_exit=""
+trap "$_exit" EXIT
+
+# XXX: yes this is very silly. flakes~!!
+nix build --impure --expr '(builtins.getFlake "git+file:.").inputs.nixpkgs.outPath' -o bench/nixpkgs
+
+export NIX_REMOTE="$(mktemp -d)"
+_exit='rm -rfv "$NIX_REMOTE"; $_exit'
+export NIX_PATH="nixpkgs=bench/nixpkgs:nixos-config=bench/configuration.nix"
+
+builds=("$@")
+
+flake_args="--extra-experimental-features 'nix-command flakes'"
+
+hyperfineArgs=(
+    --parameter-list BUILD "$(IFS=,; echo "${builds[*]}")"
+    --warmup 2 --runs 10
+)
+
+declare -A cases
+cases=(
+    [search]="{BUILD}/bin/nix $flake_args search --no-eval-cache github:nixos/nixpkgs/e1fa12d4f6c6fe19ccb59cac54b5b3f25e160870 hello"
+    [rebuild]="{BUILD}/bin/nix $flake_args eval --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'"
+    [rebuild-lh]="GC_INITIAL_HEAP_SIZE=10g {BUILD}/bin/nix eval $flake_args --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'"
+    [parse]="{BUILD}/bin/nix $flake_args eval -f bench/nixpkgs/pkgs/development/haskell-modules/hackage-packages.nix"
+)
+
+benches=(
+    rebuild
+    rebuild-lh
+    search
+    parse
+)
+
+for k in "${benches[@]}"; do
+    taskset -c 2,3 \
+        chrt -f 50 \
+        hyperfine "${hyperfineArgs[@]}"  --export-json="bench/bench-${k}.json" --export-markdown="bench/bench-${k}.md" "${cases[$k]}"
+done
+
+echo "Benchmarks summary (from ./bench/summarize.jq bench/bench-*.json)"
+bench/summarize.jq bench/*.json

bench/configuration.nix

@@ -0,0 +1,325 @@
+{
+  config,
+  pkgs,
+  lib,
+  ...
+}:
+
+{
+  boot = {
+    initrd = {
+      availableKernelModules = [
+        "xhci_pci"
+        "ahci"
+      ];
+      kernelModules = [ "dm-snapshot" ];
+      luks.devices = {
+        croot = {
+          device = "/dev/sdb";
+          allowDiscards = true;
+        };
+      };
+    };
+    kernelModules = [ "kvm-intel" ];
+    kernelPackages = pkgs.linuxPackages_latest;
+
+    loader = {
+      systemd-boot.enable = true;
+      efi.canTouchEfiVariables = true;
+    };
+  };
+
+  hardware = {
+    enableRedistributableFirmware = true;
+    cpu.intel.updateMicrocode = true;
+    opengl.driSupport32Bit = true;
+    opengl.extraPackages = with pkgs; [
+      vaapiIntel
+      intel-media-driver
+      intel-compute-runtime
+    ];
+  };
+
+  fileSystems = {
+    "/" = {
+      device = "/dev/sda2";
+      fsType = "xfs";
+      options = [ "noatime" ];
+    };
+
+    "/boot" = {
+      device = "/dev/sda1";
+      fsType = "vfat";
+    };
+
+    "/nas" = {
+      device = "nas:/";
+      fsType = "nfs4";
+      options = [
+        "ro"
+        "x-systemd.automount"
+      ];
+    };
+  };
+  swapDevices = [ { device = "/dev/swap"; } ];
+
+  networking = {
+    useDHCP = false;
+    hostName = "host";
+    wireless = {
+      enable = true;
+      interfaces = [ "eth1" ];
+    };
+    interfaces = {
+      eth0.useDHCP = true;
+      eth1.useDHCP = true;
+    };
+    wg-quick.interfaces = {
+      wg0 = {
+        address = [ "2001:db8::1" ];
+        privateKeyFile = "/etc/secrets/wg0.key";
+        peers = [
+          {
+            publicKey = "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=";
+            endpoint = "[2001:db8::2]:61021";
+            allowedIPs = [ "2001::db8:1::/64" ];
+          }
+        ];
+      };
+    };
+
+    firewall.allowedUDPPorts = [ 4567 ];
+  };
+
+  i18n = {
+    defaultLocale = "en_US.UTF-8";
+    inputMethod.enabled = "ibus";
+  };
+
+  services = {
+    xserver = {
+      enable = true;
+      layout = "us";
+      xkbVariant = "altgr-intl";
+      xkbOptions = "ctrl:nocaps";
+      libinput.enable = true;
+      wacom.enable = true;
+      videoDrivers = [ "modesetting" ];
+      modules = [ pkgs.xf86_input_wacom ];
+
+      displayManager.sx.enable = true;
+      windowManager.i3.enable = true;
+    };
+
+    udev.extraHwdb = ''
+      # not like this mattered at all
+      # we're not running udev from here
+    '';
+
+    udev.extraRules = ''
+      # ACTION=="add", SUBSYSTEM=="input", ...
+    '';
+  };
+
+  sound.enable = true;
+  hardware.pulseaudio = {
+    enable = true;
+    package = pkgs.pulseaudioFull;
+    daemon.config = {
+      lock-memory = "yes";
+      realtime-scheduling = "yes";
+      rlimit-rtprio = "-1";
+    };
+  };
+
+  programs = {
+    light.enable = true;
+    wireshark = {
+      enable = true;
+      package = pkgs.wireshark-qt;
+    };
+    gnupg.agent = {
+      enable = true;
+    };
+  };
+
+  fonts.packages = with pkgs; [
+    font-awesome
+    noto-fonts
+    noto-fonts-cjk
+    noto-fonts-emoji
+    noto-fonts-extra
+    dejavu_fonts
+    powerline-fonts
+    source-code-pro
+    cantarell-fonts
+  ];
+
+  users = {
+    mutableUsers = false;
+
+    users = {
+      user = {
+        isNormalUser = true;
+        group = "user";
+        extraGroups = [
+          "wheel"
+          "video"
+          "audio"
+          "dialout"
+          "users"
+          "kvm"
+          "wireshark"
+        ];
+        password = "unimportant";
+      };
+    };
+
+    groups = {
+      user = { };
+    };
+  };
+
+  security = {
+    pam.loginLimits = [
+      {
+        domain = "@audio";
+        item = "memlock";
+        type = "-";
+        value = "unlimited";
+      }
+      {
+        domain = "@audio";
+        item = "rtprio";
+        type = "-";
+        value = "99";
+      }
+      {
+        domain = "@audio";
+        item = "nofile";
+        type = "soft";
+        value = "99999";
+      }
+      {
+        domain = "@audio";
+        item = "nofile";
+        type = "hard";
+        value = "99999";
+      }
+    ];
+
+    sudo.extraRules = [
+      {
+        users = [ "user" ];
+        commands = [
+          {
+            command = "${pkgs.linuxPackages.cpupower}/bin/cpupower";
+            options = [ "NOPASSWD" ];
+          }
+        ];
+      }
+    ];
+  };
+
+  environment.systemPackages = with pkgs; [
+    a2jmidid
+    age
+    ardour
+    bemenu
+    blender
+    breeze-icons
+    breeze-qt5
+    bubblewrap
+    calf
+    claws-mail
+    darktable
+    duperemove
+    emacs
+    feh
+    file
+    firefox
+    fluidsynth
+    gnome3.adwaita-icon-theme
+    gnuplot
+    graphviz
+    helm
+    i3status-rust
+    inkscape
+    jack2
+    jq
+    krita
+    ldns
+    libqalculate
+    libreoffice
+    man-pages
+    nheko
+    nix-diff
+    nix-index
+    nix-output-monitor
+    open-music-kontrollers.patchmatrix
+    pamixer
+    pavucontrol
+    pciutils
+    picom
+    pwgen
+    redshift
+    ripgrep
+    rlwrap
+    silver-searcher
+    soundfont-fluid
+    whois
+    wol
+    xclip
+    xdot
+    xdotool
+    xorg.xkbcomp
+    yt-dlp
+    zathura
+    borgbackup
+    linuxPackages.cpupower
+    mtr
+    kitty
+    xf86_input_wacom
+  ];
+
+  environment.pathsToLink = [ "/share/soundfonts" ];
+
+  systemd.user.services.run-python = {
+    after = [ "network-online.target" ];
+    script = ''
+      exec ${pkgs.python3}/bin/python
+    '';
+    serviceConfig = {
+      CapabilityBoundingSet = [ "" ];
+      KeyringMode = "private";
+      LockPersonality = true;
+      MemoryDenyWriteExecute = true;
+      NoNewPrivileges = true;
+      PrivateDevices = true;
+      PrivateTmp = true;
+      PrivateUsers = true;
+      ProcSubset = "pid";
+      ProtectClock = true;
+      ProtectControlGroups = true;
+      ProtectHome = true;
+      ProtectHostname = true;
+      ProtectKernelLogs = true;
+      ProtectKernelModules = true;
+      ProtectKernelTunables = true;
+      ProtectProc = "invisible";
+      ProtectSystem = "strict";
+      RestrictAddressFamilies = "AF_INET AF_INET6";
+      RestrictNamespaces = true;
+      RestrictRealtime = true;
+      RestrictSUIDSGID = true;
+      SystemCallArchitectures = "native";
+      SystemCallFilter = [
+        "@system-service"
+        "~ @resources @privileged"
+      ];
+      UMask = "077";
+    };
+  };
+
+  system.stateVersion = "23.11";
+}

bench/summarize.jq

@@ -0,0 +1,22 @@
+#!/usr/bin/env -S jq -Mrf
+
+def round3:
+    . * 1000 | round | . / 1000
+    ;
+
+def stats($first):
+    [
+        "  mean:     \(.mean | round3)s ± \(.stddev | round3)s",
+        "            user: \(.user | round3)s | system: \(.system | round3)s",
+        "  median:   \(.median | round3)s",
+        "  range:    \(.min | round3)s ... \(.max | round3)s",
+        "  relative: \(.mean / $first.mean | round3)"
+    ]
+    | join("\n")
+    ;
+
+def fmt($first):
+    "\(.command)\n" + (. | stats($first))
+    ;
+
+[.results | .[0] as $first | .[] | fmt($first)] | join("\n\n") | (. + "\n\n---\n")

boehmgc-coroutine-sp-fallback.diff

@@ -0,0 +1,54 @@
+diff --git a/pthread_stop_world.c b/pthread_stop_world.c
+index 2b45489..0e6d8ef 100644
+--- a/pthread_stop_world.c
++++ b/pthread_stop_world.c
+@@ -776,6 +776,8 @@ STATIC void GC_restart_handler(int sig)
+ /* world is stopped.  Should not fail if it isn't.                      */
+ GC_INNER void GC_push_all_stacks(void)
+ {
++    size_t stack_limit;
++    pthread_attr_t pattr;
+     GC_bool found_me = FALSE;
+     size_t nthreads = 0;
+     int i;
+@@ -868,6 +870,40 @@ GC_INNER void GC_push_all_stacks(void)
+             hi = p->altstack + p->altstack_size;
+ #         endif
+           /* FIXME: Need to scan the normal stack too, but how ? */
++        } else {
++          #ifdef HAVE_PTHREAD_ATTR_GET_NP
++          if (pthread_attr_init(&pattr) != 0) {
++            ABORT("GC_push_all_stacks: pthread_attr_init failed!");
++          }
++          if (pthread_attr_get_np(p->id, &pattr) != 0) {
++            ABORT("GC_push_all_stacks: pthread_attr_get_np failed!");
++          }
++          #else
++          if (pthread_getattr_np(p->id, &pattr)) {
++            ABORT("GC_push_all_stacks: pthread_getattr_np failed!");
++          }
++          #endif
++          if (pthread_attr_getstacksize(&pattr, &stack_limit)) {
++            ABORT("GC_push_all_stacks: pthread_attr_getstacksize failed!");
++          }
++          if (pthread_attr_destroy(&pattr)) {
++            ABORT("GC_push_all_stacks: pthread_attr_destroy failed!");
++          }
++          // When a thread goes into a coroutine, we lose its original sp until
++          // control flow returns to the thread.
++          // While in the coroutine, the sp points outside the thread stack,
++          // so we can detect this and push the entire thread stack instead,
++          // as an approximation.
++          // We assume that the coroutine has similarly added its entire stack.
++          // This could be made accurate by cooperating with the application
++          // via new functions and/or callbacks.
++          #ifndef STACK_GROWS_UP
++            if (lo >= hi || lo < hi - stack_limit) { // sp outside stack
++              lo = hi - stack_limit;
++            }
++          #else
++          #error "STACK_GROWS_UP not supported in boost_coroutine2 (as of june 2021), so we don't support it in Nix."
++          #endif
+         }
+ #       ifdef STACKPTR_CORRECTOR_AVAILABLE
+           if (GC_sp_corrector != 0)

clang-tidy/.clang-format

@@ -0,0 +1 @@
+BasedOnStyle: llvm

clang-tidy/.editorconfig

@@ -0,0 +1,4 @@
+# LLVM style code is 2-space indented
+[*.{cc,hh}]
+indent_style = space
+indent_size = 2

clang-tidy/FixIncludes.cc

@@ -0,0 +1,90 @@
+#include "FixIncludes.hh"
+#include <clang-tidy/ClangTidyCheck.h>
+#include <clang/Basic/Diagnostic.h>
+#include <clang/Basic/SourceManager.h>
+#include <clang/Lex/PPCallbacks.h>
+#include <clang/Lex/Preprocessor.h>
+#include <llvm/ADT/StringRef.h>
+#include <llvm/Support/Debug.h>
+#include <memory>
+#include <set>
+#include <string>
+
+namespace nix::clang_tidy {
+
+using namespace clang;
+using namespace clang::tidy;
+
+class FixIncludesCallbacks : public PPCallbacks {
+public:
+  ClangTidyCheck &Check;
+  Preprocessor &PP;
+  FixIncludesCallbacks(ClangTidyCheck &Check, Preprocessor &PP)
+      : Check(Check), PP(PP) {}
+
+private:
+  bool Ignore = false;
+  virtual void LexedFileChanged(FileID FID, LexedFileChangeReason Reason,
+                                SrcMgr::CharacteristicKind FileType,
+                                FileID PrevFID, SourceLocation Loc) override;
+
+  virtual void InclusionDirective(SourceLocation HashLoc,
+                                  const Token &IncludeTok, StringRef FileName,
+                                  bool IsAngled, CharSourceRange FilenameRange,
+                                  OptionalFileEntryRef File,
+                                  StringRef SearchPath, StringRef RelativePath,
+                                  const Module *Imported,
+                                  SrcMgr::CharacteristicKind FileType) override;
+};
+
+void FixIncludesCallbacks::LexedFileChanged(FileID, LexedFileChangeReason,
+                                            SrcMgr::CharacteristicKind FileType,
+                                            FileID, SourceLocation) {
+  Ignore = FileType != SrcMgr::C_User;
+}
+
+void FixIncludesCallbacks::InclusionDirective(
+    SourceLocation, const Token &, StringRef FileName, bool IsAngled,
+    CharSourceRange FilenameRange, OptionalFileEntryRef File, StringRef,
+    StringRef, const Module *, SrcMgr::CharacteristicKind) {
+  if (Ignore)
+    return;
+
+  // FIXME: this is kinda evil, but this is a one-time fixup
+  const std::vector<std::string> SourceDirs = {"src/", "include/lix/"};
+
+  const auto Bracketize = [IsAngled](StringRef s) {
+    return IsAngled ? ("<" + s + ">").str() : ("\"" + s + "\"").str();
+  };
+
+  for (const auto &SourceDir : SourceDirs) {
+    const bool IsAlreadyFixed = FileName.starts_with("lix/lib");
+    if (File && File->getNameAsRequested().contains(SourceDir) &&
+        !IsAlreadyFixed) {
+      StringRef Name = File->getNameAsRequested();
+      auto Idx = Name.find(SourceDir);
+      assert(Idx != std::string::npos);
+      std::string Suffix = Name.drop_front(Idx + SourceDir.length()).str();
+
+      if (!Suffix.starts_with("lib")) {
+        llvm::dbgs() << "ignored: " << Suffix << "\n";
+        return;
+      }
+
+      Suffix = "lix/" + Suffix;
+
+      auto Diag = Check.diag(FilenameRange.getBegin(),
+                             "include needs to specify the source subdir");
+
+      Diag << FilenameRange
+           << FixItHint::CreateReplacement(FilenameRange, Bracketize(Suffix));
+    }
+  }
+}
+
+void FixIncludesCheck::registerPPCallbacks(const SourceManager &,
+                                           Preprocessor *PP, Preprocessor *) {
+  PP->addPPCallbacks(std::make_unique<FixIncludesCallbacks>(*this, *PP));
+}
+
+}; // namespace nix::clang_tidy

clang-tidy/FixIncludes.hh

@@ -0,0 +1,21 @@
+#pragma once
+///@file
+
+#include <clang-tidy/ClangTidyCheck.h>
+#include <clang/ASTMatchers/ASTMatchFinder.h>
+#include <llvm/ADT/StringRef.h>
+
+namespace nix::clang_tidy {
+
+using namespace clang;
+using namespace clang::tidy;
+
+class FixIncludesCheck : public ClangTidyCheck {
+    public:
+    FixIncludesCheck(StringRef Name, ClangTidyContext *Context)
+            : ClangTidyCheck(Name, Context) {}
+
+    void registerPPCallbacks(const SourceManager &SM, Preprocessor *PP, Preprocessor *ModuleExpanderPP) override;
+};
+
+};

clang-tidy/HasPrefixSuffix.cc

@@ -0,0 +1,80 @@
+#include "HasPrefixSuffix.hh"
+#include <clang/AST/ASTTypeTraits.h>
+#include <clang/AST/Expr.h>
+#include <clang/AST/PrettyPrinter.h>
+#include <clang/AST/Type.h>
+#include <clang/ASTMatchers/ASTMatchers.h>
+#include <clang/Basic/Diagnostic.h>
+#include <clang/Frontend/FrontendAction.h>
+#include <clang/Frontend/FrontendPluginRegistry.h>
+#include <clang/Tooling/Transformer/SourceCode.h>
+#include <clang/Tooling/Transformer/SourceCodeBuilders.h>
+#include <iostream>
+
+namespace nix::clang_tidy {
+using namespace clang::ast_matchers;
+using namespace clang;
+
+void HasPrefixSuffixCheck::registerMatchers(ast_matchers::MatchFinder *Finder) {
+  Finder->addMatcher(
+      traverse(clang::TK_AsIs,
+               callExpr(callee(functionDecl(anyOf(hasName("hasPrefix"),
+                                                  hasName("hasSuffix")))
+                                   .bind("callee-decl")),
+                        optionally(hasArgument(
+                            0, cxxConstructExpr(
+                                   hasDeclaration(functionDecl(hasParameter(
+                                       0, parmVarDecl(hasType(
+                                              asString("const char *")))))))
+                                   .bind("implicit-cast"))))
+                   .bind("call")),
+      this);
+}
+
+void HasPrefixSuffixCheck::check(
+    const ast_matchers::MatchFinder::MatchResult &Result) {
+
+  const auto *CalleeDecl = Result.Nodes.getNodeAs<FunctionDecl>("callee-decl");
+  auto FuncName = std::string(CalleeDecl->getName());
+  std::string NewName;
+  if (FuncName == "hasPrefix") {
+    NewName = "starts_with";
+  } else if (FuncName == "hasSuffix") {
+    NewName = "ends_with";
+  } else {
+    llvm_unreachable("nix-has-prefix: invalid callee");
+  }
+
+  const auto *MatchedDecl = Result.Nodes.getNodeAs<CallExpr>("call");
+  const auto *ImplicitConvertArg =
+      Result.Nodes.getNodeAs<CXXConstructExpr>("implicit-cast");
+
+  const auto *Lhs = MatchedDecl->getArg(0);
+  const auto *Rhs = MatchedDecl->getArg(1);
+  auto Diag = diag(MatchedDecl->getExprLoc(), FuncName + " is deprecated");
+
+  std::string Text = "";
+
+  // Form possible cast to string_view, or nothing.
+  if (ImplicitConvertArg) {
+    Text = "std::string_view(";
+    Text.append(tooling::getText(*Lhs, *Result.Context));
+    Text.append(").");
+  } else {
+    Text.append(*tooling::buildAccess(*Lhs, *Result.Context));
+  }
+
+  // Call .starts_with.
+  Text.append(NewName);
+  Text.push_back('(');
+  Text.append(tooling::getText(*Rhs, *Result.Context));
+  Text.push_back(')');
+
+  Diag << FixItHint::CreateReplacement(MatchedDecl->getSourceRange(), Text);
+
+  // for (const auto *arg : MatchedDecl->arguments()) {
+  //   arg->dumpColor();
+  //   arg->getType().dump();
+  // }
+}
+}; // namespace nix::clang_tidy

clang-tidy/HasPrefixSuffix.hh

@@ -0,0 +1,25 @@
+#pragma once
+///@file
+/// This is an example of a clang-tidy automated refactoring against the Nix
+/// codebase. The refactoring has been completed in
+/// https://gerrit.lix.systems/c/lix/+/565 so this code is around as
+/// an example.
+
+#include <clang-tidy/ClangTidyCheck.h>
+#include <clang/ASTMatchers/ASTMatchFinder.h>
+#include <llvm/ADT/StringRef.h>
+
+namespace nix::clang_tidy {
+
+using namespace clang;
+using namespace clang::tidy;
+using namespace llvm;
+
+class HasPrefixSuffixCheck : public ClangTidyCheck {
+public:
+  HasPrefixSuffixCheck(StringRef Name, ClangTidyContext *Context)
+      : ClangTidyCheck(Name, Context) {}
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+};
+}; // namespace nix::clang_tidy

clang-tidy/LixClangTidyChecks.cc

@@ -0,0 +1,19 @@
+#include <clang-tidy/ClangTidyModule.h>
+#include <clang-tidy/ClangTidyModuleRegistry.h>
+#include "FixIncludes.hh"
+#include "HasPrefixSuffix.hh"
+
+namespace nix::clang_tidy {
+using namespace clang;
+using namespace clang::tidy;
+
+class NixClangTidyChecks : public ClangTidyModule {
+    public:
+        void addCheckFactories(ClangTidyCheckFactories &CheckFactories) override {
+            CheckFactories.registerCheck<HasPrefixSuffixCheck>("lix-hasprefixsuffix");
+            CheckFactories.registerCheck<FixIncludesCheck>("lix-fixincludes");
+        }
+};
+
+static ClangTidyModuleRegistry::Add<NixClangTidyChecks> X("lix-module", "Adds lix specific checks");
+};

clang-tidy/README.md

@@ -0,0 +1,56 @@
+# Clang tidy lints for Lix
+
+This is a skeleton of a clang-tidy lints library for Lix.
+
+Currently there is one check (which is already obsolete as it has served its
+goal and is there as an example), `HasPrefixSuffixCheck`.
+
+## Running fixes/checks
+
+One file:
+
+```
+ninja -C build && clang-tidy --checks='-*,lix-*' --load=build/liblix-clang-tidy.so -p ../compile_commands.json -header-filter '\.\./src/.*\.h' --fix ../src/libcmd/installables.cc
+```
+
+Several files, in parallel:
+
+```
+ninja -C build && run-clang-tidy -checks='-*,lix-*' -load=build/liblix-clang-tidy.so -p .. -header-filter '\.\./src/.*\.h' -fix ../src | tee -a clang-tidy-result
+```
+
+## Resources
+
+* https://firefox-source-docs.mozilla.org/code-quality/static-analysis/writing-new/clang-query.html
+* https://clang.llvm.org/docs/LibASTMatchersReference.html
+* https://devblogs.microsoft.com/cppblog/exploring-clang-tooling-part-3-rewriting-code-with-clang-tidy/
+
+## Developing new checks
+
+Put something like so in `myquery.txt`:
+
+```
+set traversal     IgnoreUnlessSpelledInSource
+# ^ Ignore implicit AST nodes. May need to use AsIs depending on how you are
+# working.
+set bind-root     true
+# ^ true unless you use any .bind("foo") commands
+set print-matcher true
+enable output     dump
+match callExpr(callee(functionDecl(hasName("hasPrefix"))), optionally(hasArgument( 0, cxxConstructExpr(hasDeclaration(functionDecl(hasParameter(0, parmVarDecl(hasType(asString("const char *"))).bind("meow2"))))))))
+```
+
+Then run, e.g. `clang-query --preload hasprefix.query -p compile_commands.json src/libcmd/installables.cc`.
+
+With this you can iterate a query before writing it in C++ and suffering from
+C++.
+
+### Tips and tricks for the C++
+
+There is a function `dump()` on many things that will dump to stderr. Also
+`llvm::errs()` lets you print to stderr.
+
+When I wrote `HasPrefixSuffixCheck`, I was not really able to figure out how
+the structured replacement system was supposed to work. In principle you can
+describe the replacement with a nice DSL. Look up the Stencil system in Clang
+for details.

clang-tidy/meson.build

@@ -0,0 +1,13 @@
+project('lix-clang-tidy', ['cpp', 'c'],
+  version : '0.1',
+  default_options : ['warning_level=3', 'cpp_std=c++20'])
+
+llvm = dependency('Clang', version: '>= 14', modules: ['libclang'])
+sources = files(
+  'HasPrefixSuffix.cc',
+  'LixClangTidyChecks.cc',
+  'FixIncludes.cc',
+)
+
+shared_module('lix-clang-tidy', sources,
+  dependencies: llvm)

contrib/stack-collapse.py

@@ -0,0 +1,38 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i python3 -p python3 --pure
+
+# To be used with `--trace-function-calls` and `flamegraph.pl`.
+#
+# For example:
+#
+# nix-instantiate --trace-function-calls '<nixpkgs>' -A hello 2> nix-function-calls.trace
+# ./contrib/stack-collapse.py nix-function-calls.trace > nix-function-calls.folded
+# nix-shell -p flamegraph --run "flamegraph.pl nix-function-calls.folded > nix-function-calls.svg"
+
+import sys
+from pprint import pprint
+import fileinput
+
+stack = []
+timestack = []
+
+for line in fileinput.input():
+    components = line.strip().split(" ", 2)
+    if components[0] != "function-trace":
+        continue
+
+    direction = components[1]
+    components = components[2].rsplit(" ", 2)
+
+    loc = components[0]
+    _at = components[1]
+    time = int(components[2])
+
+    if direction == "entered":
+        stack.append(loc)
+        timestack.append(time)
+    elif direction == "exited":
+        dur = time - timestack.pop()
+        vst = ";".join(stack)
+        print(f"{vst} {dur}")
+        stack.pop()

default.nix

@@ -0,0 +1,9 @@
+(import (
+  let
+    lock = builtins.fromJSON (builtins.readFile ./flake.lock);
+  in
+  fetchTarball {
+    url = "https://github.com/edolstra/flake-compat/archive/${lock.nodes.flake-compat.locked.rev}.tar.gz";
+    sha256 = lock.nodes.flake-compat.locked.narHash;
+  }
+) { src = ./.; }).defaultNix

doc/internal-api/.gitignore

@@ -0,0 +1,3 @@
+/doxygen.cfg
+/html
+/latex

doc/internal-api/doxygen.cfg.in

@@ -0,0 +1,99 @@
+# Doxyfile 1.9.5
+
+# The PROJECT_NAME tag is a single word (or a sequence of words surrounded by
+# double-quotes, unless you are using Doxywizard) that should identify the
+# project for which the documentation is generated. This name is used in the
+# title of most generated pages and in a few other places.
+# The default value is: My Project.
+
+PROJECT_NAME           = "Nix"
+
+# The PROJECT_NUMBER tag can be used to enter a project or revision number. This
+# could be handy for archiving the generated documentation or if some version
+# control system is used.
+
+PROJECT_NUMBER         = @PACKAGE_VERSION@
+
+OUTPUT_DIRECTORY       = @docdir@
+
+# Using the PROJECT_BRIEF tag one can provide an optional one line description
+# for a project that appears at the top of each page and should give viewer a
+# quick idea about the purpose of the project. Keep the description short.
+
+PROJECT_BRIEF          = "Nix, the purely functional package manager; unstable internal interfaces"
+
+# If the GENERATE_LATEX tag is set to YES, doxygen will generate LaTeX output.
+# The default value is: YES.
+
+GENERATE_LATEX         = NO
+
+# The INPUT tag is used to specify the files and/or directories that contain
+# documented source files. You may enter file names like myfile.cpp or
+# directories like /usr/src/myproject. Separate the files or directories with
+# spaces. See also FILE_PATTERNS and EXTENSION_MAPPING
+# Note: If this tag is empty the current directory is searched.
+
+# FIXME Make this list more maintainable somehow. We could maybe generate this
+# in the Makefile, but we would need to change how `.in` files are preprocessed
+# so they can expand variables despite configure variables.
+
+INPUT                  = \
+  src/libcmd \
+  src/libexpr \
+  src/libexpr/flake \
+  tests/unit/libexpr \
+  tests/unit/libexpr/value \
+  tests/unit/libexpr/test \
+  tests/unit/libexpr/test/value \
+  src/libexpr/value \
+  src/libfetchers \
+  src/libmain \
+  src/libstore \
+  src/libstore/build \
+  src/libstore/builtins \
+  tests/unit/libstore \
+  tests/unit/libstore/test \
+  src/libutil \
+  tests/unit/libutil \
+  tests/unit/libutil/test \
+  src/nix \
+  src/nix-env \
+  src/nix-store
+
+# If the MACRO_EXPANSION tag is set to YES, doxygen will expand all macro names
+# in the source code. If set to NO, only conditional compilation will be
+# performed. Macro expansion can be done in a controlled way by setting
+# EXPAND_ONLY_PREDEF to YES.
+# The default value is: NO.
+# This tag requires that the tag ENABLE_PREPROCESSING is set to YES.
+
+MACRO_EXPANSION        = YES
+
+# If the EXPAND_ONLY_PREDEF and MACRO_EXPANSION tags are both set to YES then
+# the macro expansion is limited to the macros specified with the PREDEFINED and
+# EXPAND_AS_DEFINED tags.
+# The default value is: NO.
+# This tag requires that the tag ENABLE_PREPROCESSING is set to YES.
+
+EXPAND_ONLY_PREDEF     = YES
+
+# The INCLUDE_PATH tag can be used to specify one or more directories that
+# contain include files that are not input files but should be processed by the
+# preprocessor. Note that the INCLUDE_PATH is not recursive, so the setting of
+# RECURSIVE has no effect here.
+# This tag requires that the tag SEARCH_INCLUDES is set to YES.
+
+INCLUDE_PATH           = @RAPIDCHECK_HEADERS@
+
+# If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then this
+# tag can be used to specify a list of macro names that should be expanded. The
+# macro definition that is found in the sources will be used. Use the PREDEFINED
+# tag if you want to use a different macro definition that overrules the
+# definition found in the source code.
+# This tag requires that the tag ENABLE_PREPROCESSING is set to YES.
+
+EXPAND_AS_DEFINED      = \
+  DECLARE_COMMON_SERIALISER \
+  DECLARE_WORKER_SERIALISER \
+  DECLARE_SERVE_SERIALISER \
+  LENGTH_PREFIXED_PROTO_HELPER

doc/internal-api/meson.build

@@ -0,0 +1,34 @@
+doxygen_cfg = configure_file(
+  input : 'doxygen.cfg.in',
+  output : 'doxygen.cfg',
+  configuration : {
+    'PACKAGE_VERSION': meson.project_version(),
+    'RAPIDCHECK_HEADERS': rapidcheck_meson.get_variable('includedir'),
+    'docdir' : meson.current_build_dir(),
+  },
+)
+
+internal_api_docs = custom_target(
+  'internal-api-docs',
+  command : [
+    bash,
+    # Meson can you please just give us a `workdir` argument to custom targets...
+    '-c',
+    # We have to prefix the doxygen_cfg path with the project build root
+    # because of the cd in front.
+    'cd @0@ && @1@ @2@/@INPUT0@'.format(
+      meson.project_source_root(),
+      doxygen.full_path(),
+      meson.project_build_root(),
+    ),
+  ],
+  input : [
+    doxygen_cfg,
+  ],
+  output : 'html',
+  install : true,
+  install_dir : datadir / 'doc/nix/internal-api',
+  build_always_stale : true,
+)
+
+alias_target('internal-api-html', internal_api_docs)

doc/manual/anchors.jq

@@ -0,0 +1,31 @@
+"\\[\\]\\{#(?<anchor>[^\\}]+?)\\}" as $empty_anchor_regex |
+"\\[(?<text>[^\\]]+?)\\]\\{#(?<anchor>[^\\}]+?)\\}" as $anchor_regex |
+
+
+def transform_anchors_html:
+    . | gsub($empty_anchor_regex; "<a name=\"" + .anchor + "\"></a>")
+      | gsub($anchor_regex; "<a href=\"#" + .anchor + "\" id=\"" + .anchor + "\">" + .text + "</a>");
+
+
+def transform_anchors_strip:
+    . | gsub($empty_anchor_regex; "")
+      | gsub($anchor_regex; .text);
+
+
+def map_contents_recursively(transformer):
+    . + {
+        Chapter: (.Chapter + {
+            content: .Chapter.content | transformer,
+            sub_items: .Chapter.sub_items | map(map_contents_recursively(transformer)),
+        }),
+    };
+
+
+def process_command:
+    .[0] as $context |
+    .[1] as $body |
+    $body + {
+        sections: $body.sections | map(map_contents_recursively(if $context.renderer == "html" then transform_anchors_html else transform_anchors_strip end)),
+    };
+
+process_command

doc/manual/book.toml

@@ -0,0 +1,42 @@
+[book]
+title = "Lix Reference Manual"
+
+[build]
+create-missing = false
+
+[output.html]
+additional-css = ["custom.css"]
+additional-js = ["redirects.js"]
+# Using our GitHub mirror enables easier typo fixes since there is no easy way
+# to just submit a Gerrit CL by the web for trivial stuff.
+edit-url-template = "https://github.com/lix-project/lix/tree/main/doc/manual/{path}"
+git-repository-url = "https://git.lix.systems/lix-project/lix"
+# Folding by default would prevent things like "Ctrl+F for nix-env" from working
+# trivially, but the user should be able to fold if they want to.
+fold.enable = true
+fold.level = 30
+
+# Handles replacing @docroot@ with a path to ./src relative to that markdown file,
+# {{#include handlebars}}, and the @generated@ syntax used within these. it mostly
+# but not entirely replaces the links preprocessor (which we cannot simply use due
+# to @generated@ files living in a different directory to make meson happy). we do
+# not want to disable the links preprocessor entirely though because that requires
+# disabling *all* built-in preprocessors and selectively reenabling those we want.
+[preprocessor.substitute]
+command = "python3 doc/manual/substitute.py"
+before = ["anchors", "links"]
+
+[preprocessor.anchors]
+renderers = ["html"]
+command = "jq --from-file doc/manual/anchors.jq"
+
+[output.markdown]
+
+[output.linkcheck]
+# no Internet during the build (in the sandbox)
+follow-web-links = false
+
+# mdbook-linkcheck does not understand [foo]{#bar} style links, resulting in
+# excessive "Potential incomplete link" warnings. No other kind of warning was
+# produced at the time of writing.
+warning-policy = "ignore"

doc/manual/change-authors.yml

@@ -0,0 +1,132 @@
+# This file is a mapping of metadata for change authors, sort of like
+# maintainer-list.nix in nixpkgs.
+#
+# It's used for crediting people accurately in release notes. The release notes
+# script will link to forgejo, then to GitHub if forgejo is not present.
+#
+# When adding someone from outside the Lix project, you generally want to simply link their GitHub profile without adding a display name unless they are well-known in the community by that display name.
+#
+# See doc/manual/src/contributing/hacking.md for more documentation on this file's format and typical usage.
+9999years:
+  display_name: wiggles
+  forgejo: rbt
+  github: 9999years
+
+Artturin:
+  github: Artturin
+
+DavHau:
+  github: DavHau
+
+Kha:
+  github: Kha
+
+Lunaphied:
+  forgejo: Lunaphied
+  github: Lunaphied
+
+Qyriad:
+  forgejo: Qyriad
+  github: Qyriad
+
+SharzyL:
+  github: SharzyL
+
+alois31:
+  forgejo: alois31
+  github: alois31
+
+artemist:
+  display_name: Artemis Tosini
+  forgejo: artemist
+
+cole-h:
+  display_name: Cole Helbling
+  github: cole-h
+
+delan:
+  display_name: delan
+  forgejo: delan
+  github: delan
+
+edolstra:
+  display_name: Eelco Dolstra
+  github: edolstra
+
+ericson:
+  display_name: John Ericson
+  github: ericson2314
+
+horrors:
+  display_name: eldritch horrors
+  forgejo: pennae
+  github: pennae
+
+iFreilicht:
+  github: iFreilicht
+
+jade:
+  forgejo: jade
+  github: lf-
+
+kloenk:
+  forgejo: kloenk
+  github: kloenk
+
+lovesegfault:
+  github: lovesegfault
+
+ma27:
+  forgejo: ma27
+  github: ma27
+
+matthewbauer:
+  github: matthewbauer
+
+midnightveil:
+  display_name: julia
+  forgejo: midnightveil
+  github: midnightveil
+
+ncfavier:
+  github: ncfavier
+
+puck:
+  display_name: puck
+  forgejo: puck
+  github: puckipedia
+
+quantumjump:
+  display_name: Quantum Jump
+  github: QuantumBJump
+
+r-vdp:
+  github: r-vdp
+
+raito:
+  display_name: Raito Bezarius
+  forgejo: raito
+  github: RaitoBezarius
+
+roberth:
+  display_name: Robert Hensing
+  github: roberth
+
+thufschmitt:
+  display_name: Théophane Hufschmitt
+  github: thufschmitt
+
+tomberek:
+  display_name: Tom Bereknyei
+  github: tomberek
+
+valentin:
+  display_name: Valentin Gagarin
+  github: fricklerhandwerk
+
+winter:
+  forgejo: winter
+  github: winterqt
+
+yshui:
+  github: yshui

doc/manual/custom.css

@@ -0,0 +1,11 @@
+h1:not(:first-of-type) {
+    margin-top: 1.3em;
+}
+
+h2 {
+    margin-top: 1em;
+}
+
+.hljs-meta {
+    user-select: none;
+}

doc/manual/generate-builtin-constants.nix

@@ -0,0 +1,37 @@
+let
+  inherit (builtins) concatStringsSep attrValues mapAttrs;
+  inherit (import ./utils.nix) optionalString squash;
+in
+
+builtinsInfo:
+let
+  showBuiltin =
+    name:
+    {
+      doc,
+      type,
+      impure-only,
+    }:
+    let
+      type' = optionalString (type != null) " (${type})";
+
+      impureNotice = optionalString impure-only ''
+        > **Note**
+        >
+        > Not available in [pure evaluation mode](@docroot@/command-ref/conf-file.md#conf-pure-eval).
+      '';
+    in
+    squash ''
+      <dt id="builtins-${name}">
+        <a href="#builtins-${name}"><code>${name}</code></a>${type'}
+      </dt>
+      <dd>
+
+      ${doc}
+
+      ${impureNotice}
+
+      </dd>
+    '';
+in
+concatStringsSep "\n" (attrValues (mapAttrs showBuiltin builtinsInfo))

doc/manual/generate-builtins.nix

@@ -0,0 +1,35 @@
+let
+  inherit (builtins) concatStringsSep attrValues mapAttrs;
+  inherit (import ./utils.nix) optionalString squash;
+in
+
+builtinsInfo:
+let
+  showBuiltin =
+    name:
+    {
+      doc,
+      args,
+      arity,
+      experimental-feature,
+    }:
+    let
+      experimentalNotice = optionalString (experimental-feature != null) ''
+        This function is only available if the [${experimental-feature}](@docroot@/contributing/experimental-features.md#xp-feature-${experimental-feature}) experimental feature is enabled.
+      '';
+    in
+    squash ''
+      <dt id="builtins-${name}">
+        <a href="#builtins-${name}"><code>${name} ${listArgs args}</code></a>
+      </dt>
+      <dd>
+
+      ${doc}
+
+      ${experimentalNotice}
+
+      </dd>
+    '';
+  listArgs = args: concatStringsSep " " (map (s: "<var>${s}</var>") args);
+in
+concatStringsSep "\n" (attrValues (mapAttrs showBuiltin builtinsInfo))

doc/manual/generate-deps.py

@@ -0,0 +1,22 @@
+#!/usr/bin/env python3
+
+import glob
+import sys
+
+# meson expects makefile-style dependency declarations, i.e.
+#
+#   target: dependency...
+#
+# meson seems to pass depfiles straight on to ninja even though
+# it also parses the file itself (or at least has code to do so
+# in its tree), so we must live by ninja's rules: only slashes,
+# spaces and octothorpes can be escaped, anything else is taken
+# literally. since the rules for these aren't even the same for
+# all three we will just fail when we encounter any of them (if
+# asserts are off for some reason the depfile will likely point
+# to nonexistant paths, making everything phony and thus fine.)
+for path in glob.glob(sys.argv[1] + '/**', recursive=True):
+    assert '\\' not in path
+    assert ' ' not in path
+    assert '#' not in path
+    print("ignored:", path)

doc/manual/generate-manpage.nix

@@ -0,0 +1,224 @@
+let
+  inherit (builtins)
+    attrNames
+    attrValues
+    fromJSON
+    listToAttrs
+    mapAttrs
+    concatStringsSep
+    concatMap
+    length
+    lessThan
+    replaceStrings
+    sort
+    ;
+  inherit (import ./utils.nix)
+    concatStrings
+    optionalString
+    filterAttrs
+    trim
+    squash
+    unique
+    showSettings
+    ;
+in
+
+inlineHTML: commandDump:
+
+let
+
+  commandInfo = fromJSON commandDump;
+
+  showCommand =
+    {
+      command,
+      details,
+      filename,
+      toplevel,
+    }:
+    let
+
+      result = ''
+        > **Warning** \
+        > This program is
+        > [**experimental**](@docroot@/contributing/experimental-features.md#xp-feature-nix-command)
+        > and its interface is subject to change.
+
+        # Name
+
+        `${command}` - ${details.description}
+
+        # Synopsis
+
+        ${showSynopsis command details.args}
+
+        ${maybeSubcommands}
+
+        ${maybeStoreDocs}
+
+        ${maybeOptions}
+      '';
+
+      showSynopsis =
+        command: args:
+        let
+          showArgument = arg: "*${arg.label}*" + optionalString (!arg ? arity) "...";
+          arguments = concatStringsSep " " (map showArgument args);
+        in
+        ''
+          `${command}` [*option*...] ${arguments}
+        '';
+
+      maybeSubcommands = optionalString (details ? commands && details.commands != { }) ''
+        where *subcommand* is one of the following:
+
+        ${subcommands}
+      '';
+
+      subcommands = if length categories > 1 then listCategories else listSubcommands details.commands;
+
+      categories = sort (x: y: x.id < y.id) (
+        unique (map (cmd: cmd.category) (attrValues details.commands))
+      );
+
+      listCategories = concatStrings (map showCategory categories);
+
+      showCategory = cat: ''
+        **${toString cat.description}:**
+
+        ${listSubcommands (filterAttrs (n: v: v.category == cat) details.commands)}
+      '';
+
+      listSubcommands = cmds: concatStrings (attrValues (mapAttrs showSubcommand cmds));
+
+      showSubcommand = name: subcmd: ''
+        * [`${command} ${name}`](./${appendName filename name}.md) - ${subcmd.description}
+      '';
+
+      # TODO: move this confusing special case out of here when implementing #8496
+      maybeStoreDocs = optionalString (details ? doc) (
+        replaceStrings [ "@stores@" ] [ storeDocs ] details.doc
+      );
+
+      maybeOptions = optionalString (details.flags != { }) ''
+        # Options
+
+        ${showOptions details.flags toplevel.flags}
+
+        > **Note**
+        >
+        > See [`man nix.conf`](@docroot@/command-ref/conf-file.md#command-line-flags) for overriding configuration settings with command line flags.
+      '';
+
+      showOptions =
+        options: commonOptions:
+        let
+          allOptions = options // commonOptions;
+          showCategory = cat: ''
+            ${optionalString (cat != "") "**${cat}:**"}
+
+            ${listOptions (filterAttrs (n: v: v.category == cat) allOptions)}
+          '';
+          listOptions = opts: concatStringsSep "\n" (attrValues (mapAttrs showOption opts));
+          showOption =
+            name: option:
+            let
+              result = trim ''
+                - ${item}
+                  ${option.description}
+              '';
+              item =
+                if inlineHTML then
+                  ''<span id="opt-${name}">[`--${name}`](#opt-${name})</span> ${shortName} ${labels}''
+                else
+                  "`--${name}` ${shortName} ${labels}";
+              shortName = optionalString (option ? shortName) ("/ `-${option.shortName}`");
+              labels = optionalString (option ? labels) (concatStringsSep " " (map (s: "*${s}*") option.labels));
+            in
+            result;
+          categories = sort lessThan (unique (map (cmd: cmd.category) (attrValues allOptions)));
+        in
+        concatStrings (map showCategory categories);
+    in
+    squash result;
+
+  appendName = filename: name: (if filename == "nix" then "nix3" else filename) + "-" + name;
+
+  processCommand =
+    {
+      command,
+      details,
+      filename,
+      toplevel,
+    }:
+    let
+      cmd = {
+        inherit command;
+        name = filename + ".md";
+        value = showCommand {
+          inherit
+            command
+            details
+            filename
+            toplevel
+            ;
+        };
+      };
+      subcommand =
+        subCmd:
+        processCommand {
+          command = command + " " + subCmd;
+          details = details.commands.${subCmd};
+          filename = appendName filename subCmd;
+          inherit toplevel;
+        };
+    in
+    [ cmd ] ++ concatMap subcommand (attrNames details.commands or { });
+
+  manpages = processCommand {
+    command = "nix";
+    details = commandInfo.args;
+    filename = "nix";
+    toplevel = commandInfo.args;
+  };
+
+  storeDocs =
+    let
+      showStore =
+        name:
+        {
+          settings,
+          doc,
+          experimentalFeature,
+        }:
+        let
+          experimentalFeatureNote = optionalString (experimentalFeature != null) ''
+            > **Warning**
+            > This store is part of an
+            > [experimental feature](@docroot@/contributing/experimental-features.md).
+
+            To use this store, you need to make sure the corresponding experimental feature,
+            [`${experimentalFeature}`](@docroot@/contributing/experimental-features.md#xp-feature-${experimentalFeature}),
+            is enabled.
+            For example, include the following in [`nix.conf`](@docroot@/command-ref/conf-file.md):
+
+            ```
+            extra-experimental-features = ${experimentalFeature}
+            ```
+          '';
+        in
+        ''
+          ## ${name}
+
+          ${doc}
+
+          ${experimentalFeatureNote}
+
+          **Settings**:
+
+          ${showSettings { inherit inlineHTML; } settings}
+        '';
+    in
+    concatStrings (attrValues (mapAttrs showStore commandInfo.stores));
+in
+listToAttrs manpages

doc/manual/generate-xp-features-shortlist.nix

@@ -0,0 +1,9 @@
+with builtins;
+with import ./utils.nix;
+
+let
+  showExperimentalFeature = name: doc: ''
+    - [`${name}`](@docroot@/contributing/experimental-features.md#xp-feature-${name})
+  '';
+in
+xps: indent "  " (concatStrings (attrValues (mapAttrs showExperimentalFeature xps)))

doc/manual/generate-xp-features.nix

@@ -0,0 +1,13 @@
+with builtins;
+with import ./utils.nix;
+
+let
+  showExperimentalFeature =
+    name: doc:
+    squash ''
+      ## [`${name}`]{#xp-feature-${name}}
+
+      ${doc}
+    '';
+in
+xps: (concatStringsSep "\n" (attrValues (mapAttrs showExperimentalFeature xps)))

doc/manual/json-to-tree.py

@@ -0,0 +1,61 @@
+#!/usr/bin/env python3
+
+"""
+This script is a helper for this project's Meson buildsystem, to replace its
+usage of `nix eval --write-to`. Writing a JSON object as a nested directory
+tree is more generic, easier to maintain, and far, far less cursed. Nix
+has 'good' support for JSON output. Let's just use it.
+"""
+
+import argparse
+from pathlib import Path
+import json
+import sys
+
+name = 'json-to-tree.py'
+
+def log(*args, **kwargs):
+    kwargs['file'] = sys.stderr
+    return print(f'{name}:', *args, **kwargs)
+
+def write_dict_to_directory(current_directory: Path, data: dict, files_written=0):
+    current_directory.mkdir(parents=True, exist_ok=True)
+    for key, value in data.items():
+        nested_path = current_directory / key
+        match value:
+            case dict(nested_data):
+                files_written += write_dict_to_directory(nested_path, nested_data)
+
+            case str(content):
+                nested_path.write_text(content)
+                files_written += 1
+
+            case rest:
+                assert False, \
+                    f'should have been called on a dict or string, not {type(rest)=}\n\t{rest=}'
+
+    return files_written
+
+def main():
+    parser = argparse.ArgumentParser(name)
+    parser.add_argument('-i', '--input', type=argparse.FileType('r'), default='-',
+        help='The JSON input to operate on and output as a directory tree',
+    )
+    parser.add_argument('-o', '--output', type=Path, required=True,
+        help='The place to put the directory tree',
+    )
+    args = parser.parse_args()
+
+    json_string = args.input.read()
+
+    try:
+        data = json.loads(json_string)
+    except json.JSONDecodeError:
+        log(f'could not decode JSON from input: {json_string}')
+        raise
+
+
+    files_written = write_dict_to_directory(args.output, data)
+    log(f'wrote {files_written} files')
+
+sys.exit(main())

doc/manual/meson.build

@@ -0,0 +1,353 @@
+nix_env_for_docs = {
+  'HOME': '/dummy',
+  'NIX_CONF_DIR': '/dummy',
+  'NIX_SSL_CERT_FILE': '/dummy/no-ca-bundle.crt',
+  'NIX_STATE_DIR': '/dummy',
+  'NIX_CONFIG': 'cores = 0',
+}
+
+nix_for_docs = [ nix, '--experimental-features', 'nix-command' ]
+nix_eval_for_docs_common = nix_for_docs + [
+  'eval',
+  '-I', 'nix/corepkgs=corepkgs',
+  '--store', 'dummy://',
+  '--impure',
+]
+nix_eval_for_docs = nix_eval_for_docs_common + '--raw'
+
+conf_file_json = custom_target(
+  command : nix_for_docs + [ 'show-config', '--json' ],
+  capture : true,
+  output : 'conf-file.json',
+  env : nix_env_for_docs,
+)
+
+nix_conf_file_md_body = custom_target(
+  command : nix_eval_for_docs + [
+    '--expr',
+    '(import @INPUT0@).showSettings { inlineHTML = true; } (builtins.fromJSON (builtins.readFile @INPUT1@))',
+  ],
+  capture : true,
+  input : [
+    'utils.nix',
+    conf_file_json,
+  ],
+  output : 'conf-file.md.body',
+  env : nix_env_for_docs,
+)
+
+nix_conf_file_md = custom_target(
+  command : [ 'cat', '@INPUT@' ],
+  capture : true,
+  input : [
+    'src/command-ref/conf-file.md',
+    nix_conf_file_md_body,
+  ],
+  output : 'conf-file.md',
+)
+
+nix_exp_features_json = custom_target(
+  command : [ nix, '__dump-xp-features' ],
+  capture : true,
+  output : 'xp-features.json',
+)
+
+language_json = custom_target(
+  command: [nix, '__dump-language'],
+  output : 'language.json',
+  capture : true,
+  env : nix_env_for_docs,
+)
+
+nix3_cli_json = custom_target(
+  command : [ nix, '__dump-cli' ],
+  capture : true,
+  output : 'nix.json',
+  env : nix_env_for_docs,
+)
+
+generate_manual_deps = files(
+  'generate-deps.py',
+)
+
+# Generates builtins.md and builtin-constants.md.
+subdir('src/language')
+# Generates new-cli pages, experimental-features-shortlist.md, and conf-file.md.
+subdir('src/command-ref')
+# Generates experimental-feature-descriptions.md.
+subdir('src/contributing')
+# Generates rl-next-generated.md.
+subdir('src/release-notes')
+
+manual = custom_target(
+  'manual',
+  command : [
+    bash,
+    '-euo', 'pipefail',
+    '-c',
+    '''
+        @0@ @INPUT0@ @CURRENT_SOURCE_DIR@ > @DEPFILE@
+        cd @SOURCE_ROOT@
+        @1@ build doc/manual -d @2@ | { grep -Fv "because fragment resolution isn't implemented" || :; }
+        rm -rf @2@/manual
+        mv @2@/html @2@/manual
+        find @2@/manual -iname meson.build -delete
+    '''.format(
+      python.full_path(),
+      mdbook.full_path(),
+      meson.current_build_dir(),
+    ),
+  ],
+  input : [
+    generate_manual_deps,
+    'book.toml',
+    'anchors.jq',
+    'custom.css',
+    nix3_cli_files,
+    experimental_features_shortlist_md,
+    experimental_feature_descriptions_md,
+    conf_file_md,
+    builtins_md,
+    builtin_constants_md,
+    rl_next_generated,
+    nix,
+  ],
+  output : [
+    'manual',
+    'markdown',
+  ],
+  depfile : 'manual.d',
+  env : {
+    'RUST_LOG': 'info',
+    'MDBOOK_SUBSTITUTE_SEARCH': meson.current_build_dir() / 'src',
+  },
+)
+manual_html = manual[0]
+manual_md = manual[1]
+
+install_subdir(
+  manual_html.full_path(),
+  install_dir : datadir / 'doc/nix',
+)
+
+nix_nested_manpages = [
+  [ 'nix-env',
+    [
+      'delete-generations',
+      'install',
+      'list-generations',
+      'query',
+      'rollback',
+      'set-flag',
+      'set',
+      'switch-generation',
+      'switch-profile',
+      'uninstall',
+      'upgrade',
+    ],
+  ],
+  [ 'nix-store',
+    [
+      'add-fixed',
+      'add',
+      'delete',
+      'dump-db',
+      'dump',
+      'export',
+      'gc',
+      'generate-binary-cache-key',
+      'import',
+      'load-db',
+      'optimise',
+      'print-env',
+      'query',
+      'read-log',
+      'realise',
+      'repair-path',
+      'restore',
+      'serve',
+      'verify',
+      'verify-path',
+    ],
+  ],
+]
+
+foreach command : nix_nested_manpages
+  foreach page : command[1]
+    title = command[0] + ' --' + page
+    section = '1'
+    custom_target(
+      command : [
+        './render-manpage.sh',
+        '--out-no-smarty',
+        title,
+        section,
+        '@INPUT0@/command-ref' / command[0] / (page + '.md'),
+        '@OUTPUT0@',
+      ],
+      input : [
+        manual_md,
+        nix,
+      ],
+      output : command[0] + '-' + page + '.1',
+      install : true,
+      install_dir : mandir / 'man1',
+    )
+  endforeach
+endforeach
+
+nix3_manpages = [
+  'nix3-build',
+  'nix3-bundle',
+  'nix3-config',
+  'nix3-config-show',
+  'nix3-copy',
+  'nix3-daemon',
+  'nix3-derivation-add',
+  'nix3-derivation',
+  'nix3-derivation-show',
+  'nix3-develop',
+  'nix3-doctor',
+  'nix3-edit',
+  'nix3-eval',
+  'nix3-flake-archive',
+  'nix3-flake-check',
+  'nix3-flake-clone',
+  'nix3-flake-info',
+  'nix3-flake-init',
+  'nix3-flake-lock',
+  'nix3-flake',
+  'nix3-flake-metadata',
+  'nix3-flake-new',
+  'nix3-flake-prefetch',
+  'nix3-flake-show',
+  'nix3-flake-update',
+  'nix3-fmt',
+  'nix3-hash-file',
+  'nix3-hash',
+  'nix3-hash-path',
+  'nix3-hash-to-base16',
+  'nix3-hash-to-base32',
+  'nix3-hash-to-base64',
+  'nix3-hash-to-sri',
+  'nix3-help',
+  'nix3-help-stores',
+  'nix3-key-convert-secret-to-public',
+  'nix3-key-generate-secret',
+  'nix3-key',
+  'nix3-log',
+  'nix3-nar-cat',
+  'nix3-nar-dump-path',
+  'nix3-nar-ls',
+  'nix3-nar',
+  'nix3-path-info',
+  'nix3-print-dev-env',
+  'nix3-profile-diff-closures',
+  'nix3-profile-history',
+  'nix3-profile-install',
+  'nix3-profile-list',
+  'nix3-profile',
+  'nix3-profile-remove',
+  'nix3-profile-rollback',
+  'nix3-profile-upgrade',
+  'nix3-profile-wipe-history',
+  'nix3-realisation-info',
+  'nix3-realisation',
+  'nix3-registry-add',
+  'nix3-registry-list',
+  'nix3-registry',
+  'nix3-registry-pin',
+  'nix3-registry-remove',
+  'nix3-repl',
+  'nix3-run',
+  'nix3-search',
+  'nix3-shell',
+  'nix3-store-add-file',
+  'nix3-store-add-path',
+  'nix3-store-cat',
+  'nix3-store-copy-log',
+  'nix3-store-copy-sigs',
+  'nix3-store-delete',
+  'nix3-store-diff-closures',
+  'nix3-store-dump-path',
+  'nix3-store-gc',
+  'nix3-store-ls',
+  'nix3-store-make-content-addressed',
+  'nix3-store',
+  'nix3-store-optimise',
+  'nix3-store-path-from-hash-part',
+  'nix3-store-ping',
+  'nix3-store-prefetch-file',
+  'nix3-store-repair',
+  'nix3-store-sign',
+  'nix3-store-verify',
+  'nix3-upgrade-nix',
+  'nix3-why-depends',
+  'nix',
+]
+
+foreach page : nix3_manpages
+  section = '1'
+  custom_target(
+    command : [
+      bash,
+      '@INPUT0@',
+      page,
+      section,
+      '@INPUT1@/command-ref/new-cli/@0@.md'.format(page),
+      '@OUTPUT@',
+    ],
+    input : [
+      'render-manpage.sh',
+      manual_md,
+      nix,
+    ],
+    output : page + '.1',
+    install : true,
+    install_dir : mandir / 'man1',
+  )
+endforeach
+
+nix_manpages = [
+  [ 'nix-env', 1 ],
+  [ 'nix-store', 1 ],
+  [ 'nix-build', 1 ],
+  [ 'nix-shell', 1 ],
+  [ 'nix-instantiate', 1 ],
+  [ 'nix-collect-garbage', 1 ],
+  [ 'nix-prefetch-url', 1 ],
+  [ 'nix-channel', 1 ],
+  [ 'nix-hash', 1 ],
+  [ 'nix-copy-closure', 1 ],
+  [ 'nix.conf', 5, 'conf-file.md' ],
+  [ 'nix-daemon', 8 ],
+  [ 'nix-profiles', 5, 'files/profiles.md' ],
+]
+
+foreach entry : nix_manpages
+  title = entry[0]
+  # nix.conf.5 and nix-profiles.5 are based off of conf-file.md and files/profiles.md,
+  # rather than a stem identical to its mdbook source.
+  # Therefore we use an optional third element of this array to override the name pattern
+  md_file = entry.get(2, title + '.md')
+  section = entry[1].to_string()
+  custom_target(
+    command : [
+      bash,
+      '@INPUT0@',
+      title,
+      section,
+      '@INPUT1@/command-ref/@0@'.format(md_file),
+      '@OUTPUT@',
+    ],
+    input : [
+      'render-manpage.sh',
+      manual_md,
+      entry.get(3, []),
+      nix,
+    ],
+    output : '@0@.@1@'.format(entry[0], entry[1]),
+    install : true,
+    install_dir : mandir / 'man@0@'.format(entry[1]),
+  )
+endforeach

doc/manual/process-includes.sh

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+infile="$1"
+outfile="$2"
+shift 2
+
+# set a search path for includes. the old makefile-based system splorked
+# everything into the source tree and was thus able to not have a search
+# path, but the meson system generates intermediate files into dedicated
+# directories separate from the source. we still retain the implicit old
+# behavior for now as the base search path, once meson is the default we
+# can revisit this and remove the implicit search path entry. it's fine.
+set -- "$(dirname "$infile")" "$@"
+
+# re-implement mdBook's include directive to make it usable for terminal output and for proper @docroot@ substitution
+(grep '{{#include' "$infile" || true) | while read -r line; do
+    found=false
+    include="$(printf "$line" | sed 's/{{#include \(.*\)}}/\1/')"
+    for path in "$@"; do
+        filename="$path/$include"
+        if [ -e "$filename" ]; then
+            found=true
+            matchline="$(printf "$line" | sed 's|/|\\/|g')"
+            sed -i "/$matchline/r $filename" "$outfile"
+            sed -i "s/$matchline//" "$outfile"
+            break
+        fi
+    done
+    $found || ( echo "#include-d file '$filename' does not exist." >&2; exit 1; )
+done

doc/manual/quote-literals.xsl

@@ -0,0 +1,40 @@
+<?xml version="1.0"?>
+
+<xsl:stylesheet
+  version="1.0"
+  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+  xmlns:str="http://exslt.org/strings"
+  extension-element-prefixes="str">
+
+  <xsl:output method="xml"/>
+
+  <xsl:template match="function|command|literal|varname|filename|option|quote">`<xsl:apply-templates/>'</xsl:template>
+
+  <xsl:template match="token"><xsl:text>    </xsl:text><xsl:apply-templates /><xsl:text>
+</xsl:text></xsl:template>
+
+  <xsl:template match="screen|programlisting">
+    <screen><xsl:apply-templates select="str:split(., '&#xA;')" /></screen>
+  </xsl:template>
+
+  <xsl:template match="section[following::section]">
+    <section>
+      <xsl:apply-templates />
+      <screen><xsl:text>
+      </xsl:text></screen>
+    </section>
+  </xsl:template>
+
+  <xsl:template match="*">
+    <xsl:element name="{name(.)}" namespace="{namespace-uri(.)}">
+      <xsl:copy-of select="namespace::*" />
+      <xsl:for-each select="@*">
+	<xsl:attribute name="{name(.)}" namespace="{namespace-uri(.)}">
+	  <xsl:value-of select="."/>
+	</xsl:attribute>
+      </xsl:for-each>
+      <xsl:apply-templates/>
+    </xsl:element>
+  </xsl:template>
+
+</xsl:stylesheet>

doc/manual/rclone.conf

@@ -0,0 +1,8 @@
+[lix-docs]
+type = s3
+provider = Other
+env_auth = true
+endpoint = https://s3.lix.systems
+location_constraint = garage
+region = garage
+acl = private

doc/manual/redirects.js

@@ -0,0 +1,440 @@
+// redirect rules for URL fragments (client-side) to prevent link rot.
+// this must be done on the client side, as web servers do not see the fragment part of the URL.
+// it will only work with JavaScript enabled in the browser, but this is the best we can do here.
+// see ./_redirects for path redirects (client-side)
+
+// redirects are declared as follows:
+// each entry has as its key a path matching the requested URL path, relative to the mdBook document root.
+//
+//     IMPORTANT: it must specify the full path with file name and suffix
+//
+// each entry is itself a set of key-value pairs, where
+// - keys are anchors on the matched path.
+// - values are redirection targets relative to the current path.
+
+const redirects = {
+ "index.html": {
+    "part-advanced-topics": "advanced-topics/advanced-topics.html",
+    "chap-tuning-cores-and-jobs": "advanced-topics/cores-vs-jobs.html",
+    "chap-diff-hook": "advanced-topics/diff-hook.html",
+    "check-dirs-are-unregistered": "advanced-topics/diff-hook.html#check-dirs-are-unregistered",
+    "chap-distributed-builds": "advanced-topics/distributed-builds.html",
+    "chap-post-build-hook": "advanced-topics/post-build-hook.html",
+    "chap-post-build-hook-caveats": "advanced-topics/post-build-hook.html#implementation-caveats",
+    "chap-writing-nix-expressions": "language/index.html",
+    "part-command-ref": "command-ref/command-ref.html",
+    "conf-allow-import-from-derivation": "command-ref/conf-file.html#conf-allow-import-from-derivation",
+    "conf-allowed-uris": "command-ref/conf-file.html#conf-allowed-uris",
+    "conf-allowed-users": "command-ref/conf-file.html#conf-allowed-users",
+    "conf-auto-optimise-store": "command-ref/conf-file.html#conf-auto-optimise-store",
+    "conf-binary-cache-public-keys": "command-ref/conf-file.html#conf-binary-cache-public-keys",
+    "conf-binary-caches": "command-ref/conf-file.html#conf-binary-caches",
+    "conf-build-compress-log": "command-ref/conf-file.html#conf-build-compress-log",
+    "conf-build-cores": "command-ref/conf-file.html#conf-build-cores",
+    "conf-build-extra-chroot-dirs": "command-ref/conf-file.html#conf-build-extra-chroot-dirs",
+    "conf-build-extra-sandbox-paths": "command-ref/conf-file.html#conf-build-extra-sandbox-paths",
+    "conf-build-fallback": "command-ref/conf-file.html#conf-build-fallback",
+    "conf-build-max-jobs": "command-ref/conf-file.html#conf-build-max-jobs",
+    "conf-build-max-log-size": "command-ref/conf-file.html#conf-build-max-log-size",
+    "conf-build-max-silent-time": "command-ref/conf-file.html#conf-build-max-silent-time",
+    "conf-build-timeout": "command-ref/conf-file.html#conf-build-timeout",
+    "conf-build-use-chroot": "command-ref/conf-file.html#conf-build-use-chroot",
+    "conf-build-use-sandbox": "command-ref/conf-file.html#conf-build-use-sandbox",
+    "conf-build-use-substitutes": "command-ref/conf-file.html#conf-build-use-substitutes",
+    "conf-build-users-group": "command-ref/conf-file.html#conf-build-users-group",
+    "conf-builders": "command-ref/conf-file.html#conf-builders",
+    "conf-builders-use-substitutes": "command-ref/conf-file.html#conf-builders-use-substitutes",
+    "conf-compress-build-log": "command-ref/conf-file.html#conf-compress-build-log",
+    "conf-connect-timeout": "command-ref/conf-file.html#conf-connect-timeout",
+    "conf-cores": "command-ref/conf-file.html#conf-cores",
+    "conf-diff-hook": "command-ref/conf-file.html#conf-diff-hook",
+    "conf-env-keep-derivations": "command-ref/conf-file.html#conf-env-keep-derivations",
+    "conf-extra-binary-caches": "command-ref/conf-file.html#conf-extra-binary-caches",
+    "conf-extra-platforms": "command-ref/conf-file.html#conf-extra-platforms",
+    "conf-extra-sandbox-paths": "command-ref/conf-file.html#conf-extra-sandbox-paths",
+    "conf-extra-substituters": "command-ref/conf-file.html#conf-extra-substituters",
+    "conf-fallback": "command-ref/conf-file.html#conf-fallback",
+    "conf-fsync-metadata": "command-ref/conf-file.html#conf-fsync-metadata",
+    "conf-gc-keep-derivations": "command-ref/conf-file.html#conf-gc-keep-derivations",
+    "conf-gc-keep-outputs": "command-ref/conf-file.html#conf-gc-keep-outputs",
+    "conf-hashed-mirrors": "command-ref/conf-file.html#conf-hashed-mirrors",
+    "conf-http-connections": "command-ref/conf-file.html#conf-http-connections",
+    "conf-keep-build-log": "command-ref/conf-file.html#conf-keep-build-log",
+    "conf-keep-derivations": "command-ref/conf-file.html#conf-keep-derivations",
+    "conf-keep-env-derivations": "command-ref/conf-file.html#conf-keep-env-derivations",
+    "conf-keep-outputs": "command-ref/conf-file.html#conf-keep-outputs",
+    "conf-max-build-log-size": "command-ref/conf-file.html#conf-max-build-log-size",
+    "conf-max-free": "command-ref/conf-file.html#conf-max-free",
+    "conf-max-jobs": "command-ref/conf-file.html#conf-max-jobs",
+    "conf-max-silent-time": "command-ref/conf-file.html#conf-max-silent-time",
+    "conf-min-free": "command-ref/conf-file.html#conf-min-free",
+    "conf-narinfo-cache-negative-ttl": "command-ref/conf-file.html#conf-narinfo-cache-negative-ttl",
+    "conf-narinfo-cache-positive-ttl": "command-ref/conf-file.html#conf-narinfo-cache-positive-ttl",
+    "conf-netrc-file": "command-ref/conf-file.html#conf-netrc-file",
+    "conf-plugin-files": "command-ref/conf-file.html#conf-plugin-files",
+    "conf-post-build-hook": "command-ref/conf-file.html#conf-post-build-hook",
+    "conf-pre-build-hook": "command-ref/conf-file.html#conf-pre-build-hook",
+    "conf-require-sigs": "command-ref/conf-file.html#conf-require-sigs",
+    "conf-restrict-eval": "command-ref/conf-file.html#conf-restrict-eval",
+    "conf-run-diff-hook": "command-ref/conf-file.html#conf-run-diff-hook",
+    "conf-sandbox": "command-ref/conf-file.html#conf-sandbox",
+    "conf-sandbox-dev-shm-size": "command-ref/conf-file.html#conf-sandbox-dev-shm-size",
+    "conf-sandbox-paths": "command-ref/conf-file.html#conf-sandbox-paths",
+    "conf-secret-key-files": "command-ref/conf-file.html#conf-secret-key-files",
+    "conf-show-trace": "command-ref/conf-file.html#conf-show-trace",
+    "conf-stalled-download-timeout": "command-ref/conf-file.html#conf-stalled-download-timeout",
+    "conf-substitute": "command-ref/conf-file.html#conf-substitute",
+    "conf-substituters": "command-ref/conf-file.html#conf-substituters",
+    "conf-system": "command-ref/conf-file.html#conf-system",
+    "conf-system-features": "command-ref/conf-file.html#conf-system-features",
+    "conf-tarball-ttl": "command-ref/conf-file.html#conf-tarball-ttl",
+    "conf-timeout": "command-ref/conf-file.html#conf-timeout",
+    "conf-trace-function-calls": "command-ref/conf-file.html#conf-trace-function-calls",
+    "conf-trusted-binary-caches": "command-ref/conf-file.html#conf-trusted-binary-caches",
+    "conf-trusted-public-keys": "command-ref/conf-file.html#conf-trusted-public-keys",
+    "conf-trusted-substituters": "command-ref/conf-file.html#conf-trusted-substituters",
+    "conf-trusted-users": "command-ref/conf-file.html#conf-trusted-users",
+    "extra-sandbox-paths": "command-ref/conf-file.html#extra-sandbox-paths",
+    "sec-conf-file": "command-ref/conf-file.html",
+    "env-NIX_PATH": "command-ref/env-common.html#env-NIX_PATH",
+    "env-common": "command-ref/env-common.html",
+    "envar-remote": "command-ref/env-common.html#env-NIX_REMOTE",
+    "sec-common-env": "command-ref/env-common.html",
+    "ch-files": "command-ref/files.html",
+    "ch-main-commands": "command-ref/main-commands.html",
+    "opt-out-link": "command-ref/nix-build.html#opt-out-link",
+    "sec-nix-build": "command-ref/nix-build.html",
+    "sec-nix-channel": "command-ref/nix-channel.html",
+    "sec-nix-collect-garbage": "command-ref/nix-collect-garbage.html",
+    "sec-nix-copy-closure": "command-ref/nix-copy-closure.html",
+    "sec-nix-daemon": "command-ref/nix-daemon.html",
+    "refsec-nix-env-install-examples": "command-ref/nix-env.html#examples",
+    "rsec-nix-env-install": "command-ref/nix-env.html#operation---install",
+    "rsec-nix-env-set": "command-ref/nix-env.html#operation---set",
+    "rsec-nix-env-set-flag": "command-ref/nix-env.html#operation---set-flag",
+    "rsec-nix-env-upgrade": "command-ref/nix-env.html#operation---upgrade",
+    "sec-nix-env": "command-ref/nix-env.html",
+    "ssec-version-comparisons": "command-ref/nix-env.html#versions",
+    "sec-nix-hash": "command-ref/nix-hash.html",
+    "sec-nix-instantiate": "command-ref/nix-instantiate.html",
+    "sec-nix-prefetch-url": "command-ref/nix-prefetch-url.html",
+    "sec-nix-shell": "command-ref/nix-shell.html",
+    "ssec-nix-shell-shebang": "command-ref/nix-shell.html#use-as-a--interpreter",
+    "nixref-queries": "command-ref/nix-store.html#queries",
+    "opt-add-root": "command-ref/nix-store.html#opt-add-root",
+    "refsec-nix-store-dump": "command-ref/nix-store.html#operation---dump",
+    "refsec-nix-store-export": "command-ref/nix-store.html#operation---export",
+    "refsec-nix-store-import": "command-ref/nix-store.html#operation---import",
+    "refsec-nix-store-query": "command-ref/nix-store.html#operation---query",
+    "refsec-nix-store-verify": "command-ref/nix-store.html#operation---verify",
+    "rsec-nix-store-gc": "command-ref/nix-store.html#operation---gc",
+    "rsec-nix-store-generate-binary-cache-key": "command-ref/nix-store.html#operation---generate-binary-cache-key",
+    "rsec-nix-store-realise": "command-ref/nix-store.html#operation---realise",
+    "rsec-nix-store-serve": "command-ref/nix-store.html#operation---serve",
+    "sec-nix-store": "command-ref/nix-store.html",
+    "opt-I": "command-ref/opt-common.html#opt-I",
+    "opt-attr": "command-ref/opt-common.html#opt-attr",
+    "opt-common": "command-ref/opt-common.html",
+    "opt-cores": "command-ref/opt-common.html#opt-cores",
+    "opt-log-format": "command-ref/opt-common.html#opt-log-format",
+    "opt-max-jobs": "command-ref/opt-common.html#opt-max-jobs",
+    "opt-max-silent-time": "command-ref/opt-common.html#opt-max-silent-time",
+    "opt-timeout": "command-ref/opt-common.html#opt-timeout",
+    "sec-common-options": "command-ref/opt-common.html",
+    "ch-utilities": "command-ref/utilities.html",
+    "chap-hacking": "contributing/hacking.html",
+    "adv-attr-allowSubstitutes": "language/advanced-attributes.html#adv-attr-allowSubstitutes",
+    "adv-attr-allowedReferences": "language/advanced-attributes.html#adv-attr-allowedReferences",
+    "adv-attr-allowedRequisites": "language/advanced-attributes.html#adv-attr-allowedRequisites",
+    "adv-attr-disallowedReferences": "language/advanced-attributes.html#adv-attr-disallowedReferences",
+    "adv-attr-disallowedRequisites": "language/advanced-attributes.html#adv-attr-disallowedRequisites",
+    "adv-attr-exportReferencesGraph": "language/advanced-attributes.html#adv-attr-exportReferencesGraph",
+    "adv-attr-impureEnvVars": "language/advanced-attributes.html#adv-attr-impureEnvVars",
+    "adv-attr-outputHash": "language/advanced-attributes.html#adv-attr-outputHash",
+    "adv-attr-outputHashAlgo": "language/advanced-attributes.html#adv-attr-outputHashAlgo",
+    "adv-attr-outputHashMode": "language/advanced-attributes.html#adv-attr-outputHashMode",
+    "adv-attr-passAsFile": "language/advanced-attributes.html#adv-attr-passAsFile",
+    "adv-attr-preferLocalBuild": "language/advanced-attributes.html#adv-attr-preferLocalBuild",
+    "fixed-output-drvs": "language/advanced-attributes.html#adv-attr-outputHash",
+    "sec-advanced-attributes": "language/advanced-attributes.html",
+    "builtin-abort": "language/builtins.html#builtins-abort",
+    "builtin-add": "language/builtins.html#builtins-add",
+    "builtin-all": "language/builtins.html#builtins-all",
+    "builtin-any": "language/builtins.html#builtins-any",
+    "builtin-attrNames": "language/builtins.html#builtins-attrNames",
+    "builtin-attrValues": "language/builtins.html#builtins-attrValues",
+    "builtin-baseNameOf": "language/builtins.html#builtins-baseNameOf",
+    "builtin-bitAnd": "language/builtins.html#builtins-bitAnd",
+    "builtin-bitOr": "language/builtins.html#builtins-bitOr",
+    "builtin-bitXor": "language/builtins.html#builtins-bitXor",
+    "builtin-builtins": "language/builtins.html#builtins-builtins",
+    "builtin-compareVersions": "language/builtins.html#builtins-compareVersions",
+    "builtin-concatLists": "language/builtins.html#builtins-concatLists",
+    "builtin-concatStringsSep": "language/builtins.html#builtins-concatStringsSep",
+    "builtin-currentSystem": "language/builtins.html#builtins-currentSystem",
+    "builtin-deepSeq": "language/builtins.html#builtins-deepSeq",
+    "builtin-derivation": "language/builtins.html#builtins-derivation",
+    "builtin-dirOf": "language/builtins.html#builtins-dirOf",
+    "builtin-div": "language/builtins.html#builtins-div",
+    "builtin-elem": "language/builtins.html#builtins-elem",
+    "builtin-elemAt": "language/builtins.html#builtins-elemAt",
+    "builtin-fetchGit": "language/builtins.html#builtins-fetchGit",
+    "builtin-fetchTarball": "language/builtins.html#builtins-fetchTarball",
+    "builtin-fetchurl": "language/builtins.html#builtins-fetchurl",
+    "builtin-filterSource": "language/builtins.html#builtins-filterSource",
+    "builtin-foldl-prime": "language/builtins.html#builtins-foldl-prime",
+    "builtin-fromJSON": "language/builtins.html#builtins-fromJSON",
+    "builtin-functionArgs": "language/builtins.html#builtins-functionArgs",
+    "builtin-genList": "language/builtins.html#builtins-genList",
+    "builtin-getAttr": "language/builtins.html#builtins-getAttr",
+    "builtin-getEnv": "language/builtins.html#builtins-getEnv",
+    "builtin-hasAttr": "language/builtins.html#builtins-hasAttr",
+    "builtin-hashFile": "language/builtins.html#builtins-hashFile",
+    "builtin-hashString": "language/builtins.html#builtins-hashString",
+    "builtin-head": "language/builtins.html#builtins-head",
+    "builtin-import": "language/builtins.html#builtins-import",
+    "builtin-intersectAttrs": "language/builtins.html#builtins-intersectAttrs",
+    "builtin-isAttrs": "language/builtins.html#builtins-isAttrs",
+    "builtin-isBool": "language/builtins.html#builtins-isBool",
+    "builtin-isFloat": "language/builtins.html#builtins-isFloat",
+    "builtin-isFunction": "language/builtins.html#builtins-isFunction",
+    "builtin-isInt": "language/builtins.html#builtins-isInt",
+    "builtin-isList": "language/builtins.html#builtins-isList",
+    "builtin-isNull": "language/builtins.html#builtins-isNull",
+    "builtin-isString": "language/builtins.html#builtins-isString",
+    "builtin-length": "language/builtins.html#builtins-length",
+    "builtin-lessThan": "language/builtins.html#builtins-lessThan",
+    "builtin-listToAttrs": "language/builtins.html#builtins-listToAttrs",
+    "builtin-map": "language/builtins.html#builtins-map",
+    "builtin-match": "language/builtins.html#builtins-match",
+    "builtin-mul": "language/builtins.html#builtins-mul",
+    "builtin-parseDrvName": "language/builtins.html#builtins-parseDrvName",
+    "builtin-path": "language/builtins.html#builtins-path",
+    "builtin-pathExists": "language/builtins.html#builtins-pathExists",
+    "builtin-placeholder": "language/builtins.html#builtins-placeholder",
+    "builtin-readDir": "language/builtins.html#builtins-readDir",
+    "builtin-readFile": "language/builtins.html#builtins-readFile",
+    "builtin-removeAttrs": "language/builtins.html#builtins-removeAttrs",
+    "builtin-replaceStrings": "language/builtins.html#builtins-replaceStrings",
+    "builtin-seq": "language/builtins.html#builtins-seq",
+    "builtin-sort": "language/builtins.html#builtins-sort",
+    "builtin-split": "language/builtins.html#builtins-split",
+    "builtin-splitVersion": "language/builtins.html#builtins-splitVersion",
+    "builtin-stringLength": "language/builtins.html#builtins-stringLength",
+    "builtin-sub": "language/builtins.html#builtins-sub",
+    "builtin-substring": "language/builtins.html#builtins-substring",
+    "builtin-tail": "language/builtins.html#builtins-tail",
+    "builtin-throw": "language/builtins.html#builtins-throw",
+    "builtin-toFile": "language/builtins.html#builtins-toFile",
+    "builtin-toJSON": "language/builtins.html#builtins-toJSON",
+    "builtin-toPath": "language/builtins.html#builtins-toPath",
+    "builtin-toString": "language/builtins.html#builtins-toString",
+    "builtin-toXML": "language/builtins.html#builtins-toXML",
+    "builtin-trace": "language/builtins.html#builtins-trace",
+    "builtin-tryEval": "language/builtins.html#builtins-tryEval",
+    "builtin-typeOf": "language/builtins.html#builtins-typeOf",
+    "ssec-builtins": "language/builtins.html",
+    "attr-system": "language/derivations.html#attr-system",
+    "ssec-derivation": "language/derivations.html",
+    "ch-expression-language": "language/index.html",
+    "sec-constructs": "language/constructs.html",
+    "sect-let-language": "language/constructs.html#let-language",
+    "ss-functions": "language/constructs.html#functions",
+    "sec-language-operators": "language/operators.html",
+    "table-operators": "language/operators.html",
+    "ssec-values": "language/values.html",
+    "gloss-closure": "glossary.html#gloss-closure",
+    "gloss-derivation": "glossary.html#gloss-derivation",
+    "gloss-deriver": "glossary.html#gloss-deriver",
+    "gloss-nar": "glossary.html#gloss-nar",
+    "gloss-output-path": "glossary.html#gloss-output-path",
+    "gloss-profile": "glossary.html#gloss-profile",
+    "gloss-reachable": "glossary.html#gloss-reachable",
+    "gloss-reference": "glossary.html#gloss-reference",
+    "gloss-substitute": "glossary.html#gloss-substitute",
+    "gloss-user-env": "glossary.html#gloss-user-env",
+    "gloss-validity": "glossary.html#gloss-validity",
+    "part-glossary": "glossary.html",
+    "sec-building-source": "installation/building-source.html",
+    "ch-env-variables": "installation/env-variables.html",
+    "sec-installer-proxy-settings": "installation/env-variables.html#proxy-environment-variables",
+    "sec-nix-ssl-cert-file": "installation/env-variables.html#nix_ssl_cert_file",
+    "sec-nix-ssl-cert-file-with-nix-daemon-and-macos": "installation/env-variables.html#nix_ssl_cert_file-with-macos-and-the-nix-daemon",
+    "chap-installation": "installation/installation.html",
+    "ch-installing-binary": "installation/installing-binary.html",
+    "sect-macos-installation": "installation/installing-binary.html#macos-installation",
+    "sect-macos-installation-change-store-prefix": "installation/installing-binary.html#macos-installation",
+    "sect-macos-installation-encrypted-volume": "installation/installing-binary.html#macos-installation",
+    "sect-macos-installation-recommended-notes": "installation/installing-binary.html#macos-installation",
+    "sect-macos-installation-symlink": "installation/installing-binary.html#macos-installation",
+    "sect-multi-user-installation": "installation/installing-binary.html#multi-user-installation",
+    "sect-nix-install-binary-tarball": "installation/installing-binary.html#installing-from-a-binary-tarball",
+    "sect-nix-install-pinned-version-url": "installation/installing-binary.html#installing-a-pinned-nix-version-from-a-url",
+    "sect-single-user-installation": "installation/installing-binary.html#single-user-installation",
+    "ch-installing-source": "installation/installing-source.html",
+    "ssec-multi-user": "installation/multi-user.html",
+    "ch-nix-security": "installation/nix-security.html",
+    "sec-obtaining-source": "installation/obtaining-source.html",
+    "sec-prerequisites-source": "installation/prerequisites-source.html",
+    "sec-single-user": "installation/single-user.html",
+    "ch-supported-platforms": "installation/supported-platforms.html",
+    "ch-upgrading-nix": "installation/upgrading.html",
+    "ch-about-nix": "introduction.html",
+    "chap-introduction": "introduction.html",
+    "ch-basic-package-mgmt": "package-management/basic-package-mgmt.html",
+    "ssec-binary-cache-substituter": "package-management/binary-cache-substituter.html",
+    "sec-channels": "command-ref/nix-channel.html",
+    "ssec-copy-closure": "package-management/copy-closure.html",
+    "sec-garbage-collection": "package-management/garbage-collection.html",
+    "ssec-gc-roots": "package-management/garbage-collector-roots.html",
+    "chap-package-management": "package-management/package-management.html",
+    "sec-profiles": "package-management/profiles.html",
+    "ssec-s3-substituter": "package-management/s3-substituter.html",
+    "ssec-s3-substituter-anonymous-reads": "package-management/s3-substituter.html#anonymous-reads-to-your-s3-compatible-binary-cache",
+    "ssec-s3-substituter-authenticated-reads": "package-management/s3-substituter.html#authenticated-reads-to-your-s3-binary-cache",
+    "ssec-s3-substituter-authenticated-writes": "package-management/s3-substituter.html#authenticated-writes-to-your-s3-compatible-binary-cache",
+    "sec-sharing-packages": "package-management/sharing-packages.html",
+    "ssec-ssh-substituter": "package-management/ssh-substituter.html",
+    "chap-quick-start": "quick-start.html",
+    "sec-relnotes": "release-notes/release-notes.html",
+    "ch-relnotes-0.10.1": "release-notes/rl-0.10.1.html",
+    "ch-relnotes-0.10": "release-notes/rl-0.10.html",
+    "ssec-relnotes-0.11": "release-notes/rl-0.11.html",
+    "ssec-relnotes-0.12": "release-notes/rl-0.12.html",
+    "ssec-relnotes-0.13": "release-notes/rl-0.13.html",
+    "ssec-relnotes-0.14": "release-notes/rl-0.14.html",
+    "ssec-relnotes-0.15": "release-notes/rl-0.15.html",
+    "ssec-relnotes-0.16": "release-notes/rl-0.16.html",
+    "ch-relnotes-0.5": "release-notes/rl-0.5.html",
+    "ch-relnotes-0.6": "release-notes/rl-0.6.html",
+    "ch-relnotes-0.7": "release-notes/rl-0.7.html",
+    "ch-relnotes-0.8.1": "release-notes/rl-0.8.1.html",
+    "ch-relnotes-0.8": "release-notes/rl-0.8.html",
+    "ch-relnotes-0.9.1": "release-notes/rl-0.9.1.html",
+    "ch-relnotes-0.9.2": "release-notes/rl-0.9.2.html",
+    "ch-relnotes-0.9": "release-notes/rl-0.9.html",
+    "ssec-relnotes-1.0": "release-notes/rl-1.0.html",
+    "ssec-relnotes-1.1": "release-notes/rl-1.1.html",
+    "ssec-relnotes-1.10": "release-notes/rl-1.10.html",
+    "ssec-relnotes-1.11.10": "release-notes/rl-1.11.10.html",
+    "ssec-relnotes-1.11": "release-notes/rl-1.11.html",
+    "ssec-relnotes-1.2": "release-notes/rl-1.2.html",
+    "ssec-relnotes-1.3": "release-notes/rl-1.3.html",
+    "ssec-relnotes-1.4": "release-notes/rl-1.4.html",
+    "ssec-relnotes-1.5.1": "release-notes/rl-1.5.1.html",
+    "ssec-relnotes-1.5.2": "release-notes/rl-1.5.2.html",
+    "ssec-relnotes-1.5": "release-notes/rl-1.5.html",
+    "ssec-relnotes-1.6.1": "release-notes/rl-1.6.1.html",
+    "ssec-relnotes-1.6.0": "release-notes/rl-1.6.html",
+    "ssec-relnotes-1.7": "release-notes/rl-1.7.html",
+    "ssec-relnotes-1.8": "release-notes/rl-1.8.html",
+    "ssec-relnotes-1.9": "release-notes/rl-1.9.html",
+    "ssec-relnotes-2.0": "release-notes/rl-2.0.html",
+    "ssec-relnotes-2.1": "release-notes/rl-2.1.html",
+    "ssec-relnotes-2.2": "release-notes/rl-2.2.html",
+    "ssec-relnotes-2.3": "release-notes/rl-2.3.html",
+  },
+  "language/values.html": {
+    "simple-values": "#primitives",
+    "lists": "#list",
+    "strings": "#string",
+    "lists": "#list",
+    "attribute-sets": "#attribute-set",
+  },
+  "installation/installing-binary.html": {
+    "linux": "uninstall.html#linux",
+    "macos": "uninstall.html#macos",
+    "uninstalling": "uninstall.html",
+  }
+  "contributing/hacking.html": {
+    "nix-with-flakes": "#building-nix-with-flakes",
+    "classic-nix": "#building-nix",
+    "running-tests": "testing.html#running-tests",
+    "unit-tests": "testing.html#unit-tests",
+    "functional-tests": "testing.html#functional-tests",
+    "debugging-failing-functional-tests": "testing.html#debugging-failing-functional-tests",
+    "integration-tests": "testing.html#integration-tests",
+    "installer-tests": "testing.html#installer-tests",
+    "one-time-setup": "testing.html#one-time-setup",
+    "using-the-ci-generated-installer-for-manual-testing": "testing.html#using-the-ci-generated-installer-for-manual-testing",
+  }
+};
+
+// the following code matches the current page's URL against the set of redirects.
+//
+// it is written to minimize the latency between page load and redirect.
+// therefore we avoid function calls, copying data, and unnecessary loops.
+// IMPORTANT: we use stateful array operations and their order matters!
+//
+// matching URLs is more involved than it should be:
+//
+// 1. `document.location.pathname` can have an arbitrary prefix.
+//
+// 2. `path_to_root` is set by mdBook. it consists only of `../`s and
+//    determines the depth of `<path>` relative to the prefix:
+//
+//          `document.location.pathname`
+//        |------------------------------|
+//        /<prefix>/<path>/[<file>[.html]][#<anchor>]
+//                  |----|
+//              `path_to_root` has same number of path segments
+//
+//    source: https://phaiax.github.io/mdBook/format/theme/index-hbs.html#data
+//
+// 3. the following paths are equivalent:
+//
+//        /foo/bar/
+//        /foo/bar/index.html
+//        /foo/bar/index
+//
+//  4. the following paths are also equivalent:
+//
+//        /foo/bar/baz
+//        /foo/bar/baz.html
+//
+
+let segments = document.location.pathname.split('/');
+
+let file = segments.pop();
+
+// normalize file name
+if (file === '') { file = "index.html"; }
+else if (!file.endsWith('.html')) { file = file + '.html'; }
+
+segments.push(file);
+
+// use `path_to_root` to discern prefix from path.
+const depth = path_to_root.split('/').length;
+
+// remove segments containing prefix. the following works because
+// 1. the original `document.location.pathname` is absolute,
+//    hence first element of `segments` is always empty.
+// 2. last element of splitting `path_to_root` is also always empty.
+// 3. last element of `segments` is the file name.
+//
+// visual example:
+//
+//     '/foo/bar/baz.html'.split('/') -> [ '', 'foo', 'bar', 'baz.html' ]
+//          '../'.split('/')          -> [ '..', '' ]
+//
+// the following operations will then result in
+//
+//     path = 'bar/baz.html'
+//
+segments.splice(0, segments.length - depth);
+const path = segments.join('/');
+
+// anchor starts with the hash character (`#`),
+// but our redirect declarations don't, so we strip it.
+// example:
+//     document.location.hash -> '#foo'
+//     document.location.hash.substring(1) -> 'foo'
+const anchor = document.location.hash.substring(1);
+
+const redirect = redirects[path];
+if (redirect) {
+  const target = redirect[anchor];
+  if (target) {
+    document.location.href = target;
+  }
+}

doc/manual/render-manpage.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+lowdown_args=
+
+if [ "$1" = --out-no-smarty ]; then
+    lowdown_args=--out-no-smarty
+    shift
+fi
+
+[ "$#" = 4 ] || {
+    echo "wrong number of args passed" >&2
+    exit 1
+}
+
+title="$1"
+section="$2"
+infile="$3"
+outfile="$4"
+
+(
+    printf "Title: %s\n\n" "$title"
+    cat "$infile"
+) | lowdown -sT man --nroff-nolinks $lowdown_args -M section="$section" -o "$outfile"

doc/manual/rl-next/better-attrpath-errors.md

@@ -0,0 +1,90 @@
+---
+synopsis: "Trace which part of a `foo.bar.baz` expression errors"
+cls: 1505, 1506
+credits: Qyriad
+category: Improvements
+---
+
+Previously, if an attribute path selection expression like `linux_4_9.meta.description` it wouldn't show you which one of those parts in the attribute path, or even that that line of code is what caused evaluation of the failing expression.
+The previous error looks like this:
+
+```
+pkgs.linuxKernel.kernels.linux_4_9.meta.description
+
+error:
+       … while evaluating the attribute 'linuxKernel.kernels.linux_4_9.meta.description'
+         at /nix/store/dk2rpyb6ndvfbf19bkb2plcz5y3k8i5v-source/pkgs/top-level/linux-kernels.nix:278:5:
+          277|   } // lib.optionalAttrs config.allowAliases {
+          278|     linux_4_9 = throw "linux 4.9 was removed because it will reach its end of life within 22.11";
+             |     ^
+          279|     linux_4_14 = throw "linux 4.14 was removed because it will reach its end of life within 23.11";
+
+       … while calling the 'throw' builtin
+         at /nix/store/dk2rpyb6ndvfbf19bkb2plcz5y3k8i5v-source/pkgs/top-level/linux-kernels.nix:278:17:
+          277|   } // lib.optionalAttrs config.allowAliases {
+          278|     linux_4_9 = throw "linux 4.9 was removed because it will reach its end of life within 22.11";
+             |                 ^
+          279|     linux_4_14 = throw "linux 4.14 was removed because it will reach its end of life within 23.11";
+
+       error: linux 4.9 was removed because it will reach its end of life within 22.11
+```
+
+Now, the error will look like this:
+
+```
+pkgs.linuxKernel.kernels.linux_4_9.meta.description
+
+error:
+       … while evaluating the attribute 'linuxKernel.kernels.linux_4_9.meta.description'
+         at /nix/store/dk2rpyb6ndvfbf19bkb2plcz5y3k8i5v-source/pkgs/top-level/linux-kernels.nix:278:5:
+          277|   } // lib.optionalAttrs config.allowAliases {
+          278|     linux_4_9 = throw "linux 4.9 was removed because it will reach its end of life within 22.11";
+             |     ^
+          279|     linux_4_14 = throw "linux 4.14 was removed because it will reach its end of life within 23.11";
+
+       … while evaluating 'pkgs.linuxKernel.kernels.linux_4_9' to select 'meta' on it
+         at «string»:1:1:
+            1| pkgs.linuxKernel.kernels.linux_4_9.meta.description
+             | ^
+
+       … caused by explicit throw
+         at /nix/store/dk2rpyb6ndvfbf19bkb2plcz5y3k8i5v-source/pkgs/top-level/linux-kernels.nix:278:17:
+          277|   } // lib.optionalAttrs config.allowAliases {
+          278|     linux_4_9 = throw "linux 4.9 was removed because it will reach its end of life within 22.11";
+             |                 ^
+          279|     linux_4_14 = throw "linux 4.14 was removed because it will reach its end of life within 23.11";
+
+       error: linux 4.9 was removed because it will reach its end of life within 22.11
+```
+
+Not only does the line of code that referenced the failing attribute show up in the trace, it also tells you that it was specifically the `linux_4_9` part that failed.
+
+This includes if the failing part is a top-level binding:
+
+```
+let
+  inherit (pkgs.linuxKernel.kernels) linux_4_9;
+in linux_4_9.meta.description
+error:
+       … while evaluating 'linux_4_9' to select 'meta.description' on it
+         at «string»:3:4:
+            2|   inherit (pkgs.linuxKernel.kernels) linux_4_9;
+            3| in linux_4_9.meta.description
+             |    ^
+
+       … while evaluating the attribute 'linux_4_9'
+         at /nix/store/dk2rpyb6ndvfbf19bkb2plcz5y3k8i5v-source/pkgs/top-level/linux-kernels.nix:278:5:
+          277|   } // lib.optionalAttrs config.allowAliases {
+          278|     linux_4_9 = throw "linux 4.9 was removed because it will reach its end of life within 22.11";
+             |     ^
+          279|     linux_4_14 = throw "linux 4.14 was removed because it will reach its end of life within 23.11";
+
+       … caused by explicit throw
+         at /nix/store/dk2rpyb6ndvfbf19bkb2plcz5y3k8i5v-source/pkgs/top-level/linux-kernels.nix:278:17:
+          277|   } // lib.optionalAttrs config.allowAliases {
+          278|     linux_4_9 = throw "linux 4.9 was removed because it will reach its end of life within 22.11";
+             |                 ^
+          279|     linux_4_14 = throw "linux 4.14 was removed because it will reach its end of life within 23.11";
+
+       error: linux 4.9 was removed because it will reach its end of life within 22.11
+```

doc/manual/rl-next/build-dir.md

@@ -0,0 +1,12 @@
+---
+synopsis: "Add a `build-dir` setting to set the backing directory for builds"
+cls: 1514
+credits: [roberth, tomberek]
+category: Improvements
+---
+
+`build-dir` can now be set in the Nix configuration to choose the backing directory for the build sandbox.
+This can be useful on systems with `/tmp` on tmpfs, or simply to relocate large builds to another disk.
+
+Also, `XDG_RUNTIME_DIR` is no longer considered when selecting the default temporary directory,
+as it's not intended to be used for large amounts of data.

doc/manual/rl-next/distinguish-throw-errors.md

@@ -0,0 +1,70 @@
+---
+synopsis: "Distinguish between explicit throws and errors that happened while evaluating a throw"
+cls: 1511
+credits: Qyriad
+category: Improvements
+---
+
+Previously, errors caused by an expression like `throw "invalid argument"` were treated like an error that happened simply while some builtin function was being called:
+
+```
+let
+  throwMsg = p: throw "${p} isn't the right package";
+in throwMsg "linuz"
+
+error:
+       … while calling the 'throw' builtin
+         at «string»:2:17:
+            1| let
+            2|   throwMsg = p: throw "${p} isn't the right package";
+             |                 ^
+            3| in throwMsg "linuz"
+
+       error: linuz isn't the right package
+```
+
+But the error didn't just happen "while" calling the `throw` builtin — it's a throw error!
+Now it looks like this:
+
+```
+let
+  throwMsg = p: throw "${p} isn't the right package";
+in throwMsg "linuz"
+
+error:
+       … caused by explicit throw
+         at «string»:2:17:
+            1| let
+            2|   throwMsg = p: throw "${p} isn't the right package";
+             |                 ^
+            3| in throwMsg "linuz"
+
+       error: linuz isn't the right package
+```
+
+This also means that incorrect usage of `throw` or errors evaluating its arguments are easily distinguishable from explicit throws:
+
+```
+let
+  throwMsg = p: throw "${p} isn't the right package";
+in throwMsg { attrs = "error when coerced in string interpolation"; }
+
+error:
+       … while calling the 'throw' builtin
+         at «string»:2:17:
+            1| let
+            2|   throwMsg = p: throw "${p} isn't the right package";
+             |                 ^
+            3| in throwMsg { attrs = "error when coerced in string interpolation"; }
+
+       … while evaluating a path segment
+         at «string»:2:24:
+            1| let
+            2|   throwMsg = p: throw "${p} isn't the right package";
+             |                        ^
+            3| in throwMsg { attrs = "error when coerced in string interpolation"; }
+
+       error: cannot coerce a set to a string: { attrs = "error when coerced in string interpolation"; }
+```
+
+Here, instead of an actual thrown error, a type error happens first (trying to coerce an attribute set to a string), but that type error happened *while* calling `throw`.

doc/manual/rl-next/fix-gc-dry-run.md

@@ -0,0 +1,29 @@
+---
+synopsis: Fix nix-collect-garbage --dry-run
+issues: [fj#432]
+cls: [1566]
+category: Fixes
+credits: [quantumjump]
+---
+
+`nix-collect-garbage --dry-run` did not previously give any output - it simply
+exited without even checking to see what paths would be deleted.
+
+```
+$ nix-collect-garbage --dry-run
+$
+```
+
+We updated the behaviour of the flag such that instead it prints out how many
+paths it *would* delete, but doesn't actually delete them.
+
+```
+$ nix-collect-garbage --dry-run
+finding garbage collector roots...
+determining live/dead paths...
+...
+<nix store paths>
+...
+2670 store paths deleted, 0.00MiB freed
+$
+```

doc/manual/rl-next/fod-failure-includes-url.md

@@ -0,0 +1,16 @@
+---
+synopsis: "Hash mismatch diagnostics for fixed-output derivations include the URL"
+cls: [1536]
+credits: [jade]
+category: Improvements
+---
+
+Now, when building fixed-output derivations, Lix will guess the URL that was used in the derivation using the `url` or `urls` properties in the derivation environment.
+This is a layering violation but making these diagnostics tractable when there are multiple instances of the `AAAA` hash is too significant of an improvement to pass it up.
+
+```
+error: hash mismatch in fixed-output derivation '/nix/store/sjfw324j4533lwnpmr5z4icpb85r63ai-x1.drv':
+        likely URL: https://meow.puppy.forge/puppy.tar.gz
+         specified: sha256-AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=
+            got:    sha256-a1Qvp3FOOkWpL9kFHgugU1ok5UtRPSu+NwCZKbbaEro=
+```

doc/manual/rl-next/multiline-log-format.md

@@ -0,0 +1,14 @@
+---
+synopsis: Add log formats `multiline` and `multiline-with-logs`
+cls: [1369]
+credits: [kloenk]
+category: Improvements
+---
+
+Added two new log formats (`multiline` and `multiline-with-logs`) that display
+current activities below each other for better visibility.
+
+These formats attempt to use the maximum available lines
+(defaulting to 25 if unable to determine) and print up to that many lines.
+The status bar is displayed as the first line, with each subsequent
+activity on its own line.

doc/manual/rl-next/nix-copy-is-fast.md

@@ -0,0 +1,12 @@
+---
+synopsis: "`nix copy` is now several times faster at `querying info about /nix/store/...`"
+cls: [1462]
+issues: [fj#366]
+credits: [jade]
+category: Fixes
+---
+
+We fixed a locking bug that serialized `querying info about /nix/store/...`
+onto just one thread such that it was eating `O(paths to copy * latency)` time
+while setting up to copy paths to s3 and other stores. It is now `nproc` times
+faster.

doc/manual/rl-next/old-protocol-removal.md

@@ -0,0 +1,21 @@
+---
+synopsis: "Lix no longer speaks the Nix remote-build worker protocol to clients or servers older than CppNix 2.3"
+cls: [1207, 1208, 1206, 1205, 1204, 1203, 1479]
+issues: [fj#325]
+credits: [jade]
+category: Breaking Changes
+---
+
+CppNix 2.3 was released in 2019, and is the new oldest supported version. We
+will increase our support baseline in the future up to a final version of CppNix
+2.18 (which may happen soon given that it is the only still-packaged and thus
+still-tested >2.3 version), but this step already removes a significant amount
+of dead, untested, code paths.
+
+Lix speaks the same version of the protocol as CppNix 2.18 and that fact will
+never change in the future; the Lix plans to replace the protocol for evolution
+will entail a complete incompatible replacement that will be supported in
+parallel with the old protocol. Lix will thus retain remote build compatibility
+with CppNix as long as CppNix maintains protocol compatibility with 2.18, and
+as long as Lix retains legacy protocol support (which will likely be a long
+time given that we plan to convert it to a frozen-in-time shim).

doc/manual/rl-next/registry-add-shorthand-only.md

@@ -0,0 +1,10 @@
+---
+synopsis: "`nix registry add` now requires a shorthand flakeref on the 'from' side"
+cls: 1494
+credits: delan
+category: Improvements
+---
+
+The 'from' argument must now be a shorthand flakeref like `nixpkgs` or `nixpkgs/nixos-20.03`, making it harder to accidentally swap the 'from' and 'to' arguments.
+
+Registry entries that map from other flake URLs can still be specified in registry.json, the `nix.registry` option in NixOS, or the `--override-flake` option in the CLI, but they are not guaranteed to work correctly.

doc/manual/rl-next/reject-flake-config.md

@@ -0,0 +1,9 @@
+---
+synopsis: Allow automatic rejection of configuration options from flakes
+cls: [1541]
+credits: [alois31]
+category: Improvements
+---
+
+Setting `accept-flake-config` to `false` now respects user choice by automatically rejecting configuration options set by flakes.
+The old behaviour of asking each time is still available (and default) by setting it to the special value `ask`.

doc/manual/rl-next/repl-complete-colon.md

@@ -0,0 +1,8 @@
+---
+synopsis: "`nix repl` now allows tab-completing the special repl :colon commands"
+cls: 1367
+credits: Qyriad
+category: Improvements
+---
+
+The REPL (`nix repl`) supports pressing `<TAB>` to complete a partial expression, but now also supports completing the special :colon commands as well (`:b`, `:edit`, `:doc`, etc), if the line starts with a colon.

doc/manual/rl-next/sanitizers.md

@@ -0,0 +1,10 @@
+---
+synopsis: "Lix now supports building with UndefinedBehaviorSanitizer"
+cls: [1483]
+credits: [jade]
+category: Development
+---
+
+You can now build Lix with the configuration option `-Db_sanitize=undefined` and it will both work and pass tests. AddressSanitizer support is also coming soon.
+
+For a list of undefined behaviour fixed by sanitizer usage, see [the gerrit topic "undefined-behaviour"](https://gerrit.lix.systems/q/topic:%22undefined-behaviour%22).

doc/manual/src/SUMMARY.md

@@ -0,0 +1,250 @@
+# Table of Contents
+
+- [Introduction](introduction.md)
+- [Quick Start](quick-start.md)
+- [Installation](installation/installation.md)
+  - [Supported Platforms](installation/supported-platforms.md)
+  - [Installing a Binary Distribution](installation/installing-binary.md)
+  - [Installing Lix from Source](installation/installing-source.md)
+    - [Prerequisites](installation/prerequisites-source.md)
+    - [Obtaining a Source Distribution](installation/obtaining-source.md)
+    - [Building Lix from Source](installation/building-source.md)
+  - [Using Lix within Docker](installation/installing-docker.md)
+  - [Security](installation/nix-security.md)
+    - [Single-User Mode](installation/single-user.md)
+    - [Multi-User Mode](installation/multi-user.md)
+  - [Environment Variables](installation/env-variables.md)
+  - [Upgrading Lix](installation/upgrading.md)
+  - [Uninstalling Lix](installation/uninstall.md)
+- [Package Management](package-management/package-management.md)
+  - [Basic Package Management](package-management/basic-package-mgmt.md)
+  - [Profiles](package-management/profiles.md)
+  - [Garbage Collection](package-management/garbage-collection.md)
+    - [Garbage Collector Roots](package-management/garbage-collector-roots.md)
+  - [Sharing Packages Between Machines](package-management/sharing-packages.md)
+    - [Serving a Nix store via HTTP](package-management/binary-cache-substituter.md)
+    - [Copying Closures via SSH](package-management/copy-closure.md)
+    - [Serving a Nix store via SSH](package-management/ssh-substituter.md)
+    - [Serving a Nix store via S3](package-management/s3-substituter.md)
+- [Nix Language](language/index.md)
+  - [Data Types](language/values.md)
+  - [Language Constructs](language/constructs.md)
+    - [String interpolation](language/string-interpolation.md)
+  - [Operators](language/operators.md)
+  - [Derivations](language/derivations.md)
+    - [Advanced Attributes](language/advanced-attributes.md)
+  - [Built-in Constants](language/builtin-constants.md)
+  - [Built-in Functions](language/builtins.md)
+- [Advanced Topics](advanced-topics/advanced-topics.md)
+  - [Remote Builds](advanced-topics/distributed-builds.md)
+  - [Tuning Cores and Jobs](advanced-topics/cores-vs-jobs.md)
+  - [Verifying Build Reproducibility](advanced-topics/diff-hook.md)
+  - [Using the `post-build-hook`](advanced-topics/post-build-hook.md)
+- [Command Reference](command-ref/command-ref.md)
+  - [Common Options](command-ref/opt-common.md)
+  - [Common Environment Variables](command-ref/env-common.md)
+  - [Main Commands](command-ref/main-commands.md)
+    - [nix-build](command-ref/nix-build.md)
+    - [nix-shell](command-ref/nix-shell.md)
+    - [nix-store](command-ref/nix-store.md)
+      - [nix-store --add-fixed](command-ref/nix-store/add-fixed.md)
+      - [nix-store --add](command-ref/nix-store/add.md)
+      - [nix-store --delete](command-ref/nix-store/delete.md)
+      - [nix-store --dump-db](command-ref/nix-store/dump-db.md)
+      - [nix-store --dump](command-ref/nix-store/dump.md)
+      - [nix-store --export](command-ref/nix-store/export.md)
+      - [nix-store --gc](command-ref/nix-store/gc.md)
+      - [nix-store --generate-binary-cache-key](command-ref/nix-store/generate-binary-cache-key.md)
+      - [nix-store --import](command-ref/nix-store/import.md)
+      - [nix-store --load-db](command-ref/nix-store/load-db.md)
+      - [nix-store --optimise](command-ref/nix-store/optimise.md)
+      - [nix-store --print-env](command-ref/nix-store/print-env.md)
+      - [nix-store --query](command-ref/nix-store/query.md)
+      - [nix-store --read-log](command-ref/nix-store/read-log.md)
+      - [nix-store --realise](command-ref/nix-store/realise.md)
+      - [nix-store --repair-path](command-ref/nix-store/repair-path.md)
+      - [nix-store --restore](command-ref/nix-store/restore.md)
+      - [nix-store --serve](command-ref/nix-store/serve.md)
+      - [nix-store --verify-path](command-ref/nix-store/verify-path.md)
+      - [nix-store --verify](command-ref/nix-store/verify.md)
+    - [nix-env](command-ref/nix-env.md)
+      - [nix-env --delete-generations](command-ref/nix-env/delete-generations.md)
+      - [nix-env --install](command-ref/nix-env/install.md)
+      - [nix-env --list-generations](command-ref/nix-env/list-generations.md)
+      - [nix-env --query](command-ref/nix-env/query.md)
+      - [nix-env --rollback](command-ref/nix-env/rollback.md)
+      - [nix-env --set-flag](command-ref/nix-env/set-flag.md)
+      - [nix-env --set](command-ref/nix-env/set.md)
+      - [nix-env --switch-generation](command-ref/nix-env/switch-generation.md)
+      - [nix-env --switch-profile](command-ref/nix-env/switch-profile.md)
+      - [nix-env --uninstall](command-ref/nix-env/uninstall.md)
+      - [nix-env --upgrade](command-ref/nix-env/upgrade.md)
+  - [Utilities](command-ref/utilities.md)
+    - [nix-channel](command-ref/nix-channel.md)
+    - [nix-collect-garbage](command-ref/nix-collect-garbage.md)
+    - [nix-copy-closure](command-ref/nix-copy-closure.md)
+    - [nix-daemon](command-ref/nix-daemon.md)
+    - [nix-hash](command-ref/nix-hash.md)
+    - [nix-instantiate](command-ref/nix-instantiate.md)
+    - [nix-prefetch-url](command-ref/nix-prefetch-url.md)
+  - [Experimental Commands](command-ref/experimental-commands.md)
+    - [nix](command-ref/new-cli/nix.md)
+    - [nix build](command-ref/new-cli/nix3-build.md)
+    - [nix bundle](command-ref/new-cli/nix3-bundle.md)
+    - [nix config](command-ref/new-cli/nix3-config.md)
+    - [nix config show](command-ref/new-cli/nix3-config-show.md)
+    - [nix copy](command-ref/new-cli/nix3-copy.md)
+    - [nix daemon](command-ref/new-cli/nix3-daemon.md)
+    - [nix derivation](command-ref/new-cli/nix3-derivation.md)
+    - [nix derivation add](command-ref/new-cli/nix3-derivation-add.md)
+    - [nix derivation show](command-ref/new-cli/nix3-derivation-show.md)
+    - [nix develop](command-ref/new-cli/nix3-develop.md)
+    - [nix doctor](command-ref/new-cli/nix3-doctor.md)
+    - [nix edit](command-ref/new-cli/nix3-edit.md)
+    - [nix eval](command-ref/new-cli/nix3-eval.md)
+    - [nix flake](command-ref/new-cli/nix3-flake.md)
+    - [nix flake archive](command-ref/new-cli/nix3-flake-archive.md)
+    - [nix flake check](command-ref/new-cli/nix3-flake-check.md)
+    - [nix flake clone](command-ref/new-cli/nix3-flake-clone.md)
+    - [nix flake info](command-ref/new-cli/nix3-flake-info.md)
+    - [nix flake init](command-ref/new-cli/nix3-flake-init.md)
+    - [nix flake lock](command-ref/new-cli/nix3-flake-lock.md)
+    - [nix flake metadata](command-ref/new-cli/nix3-flake-metadata.md)
+    - [nix flake new](command-ref/new-cli/nix3-flake-new.md)
+    - [nix flake prefetch](command-ref/new-cli/nix3-flake-prefetch.md)
+    - [nix flake show](command-ref/new-cli/nix3-flake-show.md)
+    - [nix flake update](command-ref/new-cli/nix3-flake-update.md)
+    - [nix fmt](command-ref/new-cli/nix3-fmt.md)
+    - [nix hash](command-ref/new-cli/nix3-hash.md)
+    - [nix hash file](command-ref/new-cli/nix3-hash-file.md)
+    - [nix hash path](command-ref/new-cli/nix3-hash-path.md)
+    - [nix hash to-base16](command-ref/new-cli/nix3-hash-to-base16.md)
+    - [nix hash to-base32](command-ref/new-cli/nix3-hash-to-base32.md)
+    - [nix hash to-base64](command-ref/new-cli/nix3-hash-to-base64.md)
+    - [nix hash to-sri](command-ref/new-cli/nix3-hash-to-sri.md)
+    - [nix help](command-ref/new-cli/nix3-help.md)
+    - [nix help-stores](command-ref/new-cli/nix3-help-stores.md)
+    - [nix key](command-ref/new-cli/nix3-key.md)
+    - [nix key convert-secret-to-public](command-ref/new-cli/nix3-key-convert-secret-to-public.md)
+    - [nix key generate-secret](command-ref/new-cli/nix3-key-generate-secret.md)
+    - [nix log](command-ref/new-cli/nix3-log.md)
+    - [nix nar](command-ref/new-cli/nix3-nar.md)
+    - [nix nar cat](command-ref/new-cli/nix3-nar-cat.md)
+    - [nix nar dump-path](command-ref/new-cli/nix3-nar-dump-path.md)
+    - [nix nar ls](command-ref/new-cli/nix3-nar-ls.md)
+    - [nix path-info](command-ref/new-cli/nix3-path-info.md)
+    - [nix print-dev-env](command-ref/new-cli/nix3-print-dev-env.md)
+    - [nix profile](command-ref/new-cli/nix3-profile.md)
+    - [nix profile diff-closures](command-ref/new-cli/nix3-profile-diff-closures.md)
+    - [nix profile history](command-ref/new-cli/nix3-profile-history.md)
+    - [nix profile install](command-ref/new-cli/nix3-profile-install.md)
+    - [nix profile list](command-ref/new-cli/nix3-profile-list.md)
+    - [nix profile remove](command-ref/new-cli/nix3-profile-remove.md)
+    - [nix profile rollback](command-ref/new-cli/nix3-profile-rollback.md)
+    - [nix profile upgrade](command-ref/new-cli/nix3-profile-upgrade.md)
+    - [nix profile wipe-history](command-ref/new-cli/nix3-profile-wipe-history.md)
+    - [nix realisation](command-ref/new-cli/nix3-realisation.md)
+    - [nix realisation info](command-ref/new-cli/nix3-realisation-info.md)
+    - [nix registry](command-ref/new-cli/nix3-registry.md)
+    - [nix registry add](command-ref/new-cli/nix3-registry-add.md)
+    - [nix registry list](command-ref/new-cli/nix3-registry-list.md)
+    - [nix registry pin](command-ref/new-cli/nix3-registry-pin.md)
+    - [nix registry remove](command-ref/new-cli/nix3-registry-remove.md)
+    - [nix repl](command-ref/new-cli/nix3-repl.md)
+    - [nix run](command-ref/new-cli/nix3-run.md)
+    - [nix search](command-ref/new-cli/nix3-search.md)
+    - [nix shell](command-ref/new-cli/nix3-shell.md)
+    - [nix store](command-ref/new-cli/nix3-store.md)
+    - [nix store add-file](command-ref/new-cli/nix3-store-add-file.md)
+    - [nix store add-path](command-ref/new-cli/nix3-store-add-path.md)
+    - [nix store cat](command-ref/new-cli/nix3-store-cat.md)
+    - [nix store copy-log](command-ref/new-cli/nix3-store-copy-log.md)
+    - [nix store copy-sigs](command-ref/new-cli/nix3-store-copy-sigs.md)
+    - [nix store delete](command-ref/new-cli/nix3-store-delete.md)
+    - [nix store diff-closures](command-ref/new-cli/nix3-store-diff-closures.md)
+    - [nix store dump-path](command-ref/new-cli/nix3-store-dump-path.md)
+    - [nix store gc](command-ref/new-cli/nix3-store-gc.md)
+    - [nix store ls](command-ref/new-cli/nix3-store-ls.md)
+    - [nix store make-content-addressed](command-ref/new-cli/nix3-store-make-content-addressed.md)
+    - [nix store optimise](command-ref/new-cli/nix3-store-optimise.md)
+    - [nix store path-from-hash-part](command-ref/new-cli/nix3-store-path-from-hash-part.md)
+    - [nix store ping](command-ref/new-cli/nix3-store-ping.md)
+    - [nix store prefetch-file](command-ref/new-cli/nix3-store-prefetch-file.md)
+    - [nix store repair](command-ref/new-cli/nix3-store-repair.md)
+    - [nix store sign](command-ref/new-cli/nix3-store-sign.md)
+    - [nix store verify](command-ref/new-cli/nix3-store-verify.md)
+    - [nix upgrade-nix](command-ref/new-cli/nix3-upgrade-nix.md)
+    - [nix why-depends](command-ref/new-cli/nix3-why-depends.md)
+  - [Files](command-ref/files.md)
+    - [nix.conf](command-ref/conf-file.md)
+    - [Profiles](command-ref/files/profiles.md)
+      - [manifest.nix](command-ref/files/manifest.nix.md)
+      - [manifest.json](command-ref/files/manifest.json.md)
+    - [Channels](command-ref/files/channels.md)
+    - [Default Nix expression](command-ref/files/default-nix-expression.md)
+- [Architecture and Design](architecture/architecture.md)
+  - [File System Object](architecture/file-system-object.md)
+- [Protocols](protocols/protocols.md)
+  - [Serving Tarball Flakes](protocols/tarball-fetcher.md)
+  - [Derivation "ATerm" file format](protocols/derivation-aterm.md)
+- [Glossary](glossary.md)
+- [Contributing](contributing/contributing.md)
+  - [Hacking](contributing/hacking.md)
+  - [Testing](contributing/testing.md)
+  - [Experimental Features](contributing/experimental-features.md)
+  - [CLI guideline](contributing/cli-guideline.md)
+  - [C++ style guide](contributing/cxx.md)
+- [Release Notes](release-notes/release-notes.md)
+  - [Upcoming release](release-notes/rl-next.md)
+  <!-- RELENG-AUTO-INSERTION-MARKER (see releng/release_notes.py) -->
+  - [Lix 2.90 (FIXME date)](release-notes/rl-2.90.md)
+  - [Nix 2.18 (2023-09-20)](release-notes/rl-2.18.md)
+  - [Nix 2.17 (2023-07-24)](release-notes/rl-2.17.md)
+  - [Nix 2.16 (2023-05-31)](release-notes/rl-2.16.md)
+  - [Nix 2.15 (2023-04-11)](release-notes/rl-2.15.md)
+  - [Nix 2.14 (2023-02-28)](release-notes/rl-2.14.md)
+  - [Nix 2.13 (2023-01-17)](release-notes/rl-2.13.md)
+  - [Nix 2.12 (2022-12-06)](release-notes/rl-2.12.md)
+  - [Nix 2.11 (2022-08-25)](release-notes/rl-2.11.md)
+  - [Nix 2.10 (2022-07-11)](release-notes/rl-2.10.md)
+  - [Nix 2.9 (2022-05-30)](release-notes/rl-2.9.md)
+  - [Nix 2.8 (2022-04-19)](release-notes/rl-2.8.md)
+  - [Nix 2.7 (2022-03-07)](release-notes/rl-2.7.md)
+  - [Nix 2.6 (2022-01-24)](release-notes/rl-2.6.md)
+  - [Nix 2.5 (2021-12-13)](release-notes/rl-2.5.md)
+  - [Nix 2.4 (2021-11-01)](release-notes/rl-2.4.md)
+  - [Nix 2.3 (2019-09-04)](release-notes/rl-2.3.md)
+  - [Nix 2.2 (2019-01-11)](release-notes/rl-2.2.md)
+  - [Nix 2.1 (2018-09-02)](release-notes/rl-2.1.md)
+  - [Nix 2.0 (2018-02-22)](release-notes/rl-2.0.md)
+  - [Nix 1.11.10 (2017-06-12)](release-notes/rl-1.11.10.md)
+  - [Nix 1.11 (2016-01-19)](release-notes/rl-1.11.md)
+  - [Nix 1.10 (2015-09-03)](release-notes/rl-1.10.md)
+  - [Nix 1.9 (2015-06-12)](release-notes/rl-1.9.md)
+  - [Nix 1.8 (2014-12-14)](release-notes/rl-1.8.md)
+  - [Nix 1.7 (2014-04-11)](release-notes/rl-1.7.md)
+  - [Nix 1.6.1 (2013-10-28)](release-notes/rl-1.6.1.md)
+  - [Nix 1.6 (2013-09-10)](release-notes/rl-1.6.md)
+  - [Nix 1.5.2 (2013-05-13)](release-notes/rl-1.5.2.md)
+  - [Nix 1.5 (2013-02-27)](release-notes/rl-1.5.md)
+  - [Nix 1.4 (2013-02-26)](release-notes/rl-1.4.md)
+  - [Nix 1.3 (2013-01-04)](release-notes/rl-1.3.md)
+  - [Nix 1.2 (2012-12-06)](release-notes/rl-1.2.md)
+  - [Nix 1.1 (2012-07-18)](release-notes/rl-1.1.md)
+  - [Nix 1.0 (2012-05-11)](release-notes/rl-1.0.md)
+  - [Nix 0.16 (2010-08-17)](release-notes/rl-0.16.md)
+  - [Nix 0.15 (2010-03-17)](release-notes/rl-0.15.md)
+  - [Nix 0.14 (2010-02-04)](release-notes/rl-0.14.md)
+  - [Nix 0.13 (2009-11-05)](release-notes/rl-0.13.md)
+  - [Nix 0.12 (2008-11-20)](release-notes/rl-0.12.md)
+  - [Nix 0.11 (2007-12-31)](release-notes/rl-0.11.md)
+  - [Nix 0.10.1 (2006-10-11)](release-notes/rl-0.10.1.md)
+  - [Nix 0.10 (2006-10-06)](release-notes/rl-0.10.md)
+  - [Nix 0.9.2 (2005-09-21)](release-notes/rl-0.9.2.md)
+  - [Nix 0.9.1 (2005-09-20)](release-notes/rl-0.9.1.md)
+  - [Nix 0.9 (2005-09-16)](release-notes/rl-0.9.md)
+  - [Nix 0.8.1 (2005-04-13)](release-notes/rl-0.8.1.md)
+  - [Nix 0.8 (2005-04-11)](release-notes/rl-0.8.md)
+  - [Nix 0.7 (2005-01-12)](release-notes/rl-0.7.md)
+  - [Nix 0.6 (2004-11-14)](release-notes/rl-0.6.md)
+  - [Nix 0.5 and earlier](release-notes/rl-0.5.md)

doc/manual/src/_redirects

@@ -0,0 +1,29 @@
+# redirect rules for paths (server-side) to prevent link rot.
+# see ./redirects.js for redirects based on URL fragments (client-side)
+#
+# concrete user story this supports:
+# - user finds URL to the manual for Nix x.y
+# - Nix x.z (z > y) is the most recent release
+# - updating the version in the URL will show the right thing
+#
+# format documentation:
+# - https://docs.netlify.com/routing/redirects/#syntax-for-the-redirects-file
+# - https://docs.netlify.com/routing/redirects/redirect-options/
+#
+# conventions:
+# - always force (<CODE>!) since this allows re-using file names
+# - group related paths to ease readability
+# - always append new redirects to the end of the file
+# - redirects that should have been there but are missing can be inserted where they belong
+
+/expressions/expression-language /language/ 301!
+/expressions/language-values /language/values 301!
+/expressions/language-constructs /language/constructs 301!
+/expressions/language-operators /language/operators 301!
+/expressions/* /language/:splat 301!
+
+/package-management/basic-package-mgmt /command-ref/nix-env 301!
+
+/package-management/channels* /command-ref/nix-channel 301!
+
+/package-management/s3-substituter* /command-ref/new-cli/nix3-help-stores#s3-binary-cache-store 301!

doc/manual/src/advanced-topics/advanced-topics.md

@@ -0,0 +1 @@
+This section lists advanced topics related to builds and builds performance

doc/manual/src/advanced-topics/cores-vs-jobs.md

@@ -0,0 +1,39 @@
+# Tuning Cores and Jobs
+
+Lix has two relevant settings with regards to how your CPU cores will
+be utilized: `cores` and `max-jobs`. This chapter will talk about what
+they are, how they interact, and their configuration trade-offs.
+
+  - `max-jobs`\
+    Dictates how many separate derivations will be built at the same
+    time. If you set this to zero, the local machine will do no
+    builds.  Lix will still substitute from binary caches, and build
+    remotely if remote builders are configured.
+
+  - `cores`\
+    Suggests how many cores each derivation should use. Similar to
+    `make -j`.
+
+The `cores` setting determines the value of
+`NIX_BUILD_CORES`. `NIX_BUILD_CORES` is equal to `cores`, unless
+`cores` equals `0`, in which case `NIX_BUILD_CORES` will be the total
+number of cores in the system.
+
+The maximum number of consumed cores is a simple multiplication,
+`max-jobs` \* `NIX_BUILD_CORES`.
+
+The balance on how to set these two independent variables depends upon
+each builder's workload and hardware. Here are a few example scenarios
+on a machine with 24 cores:
+
+| `max-jobs` | `cores` | `NIX_BUILD_CORES` | Maximum Processes | Result                                                                                                                                                                                                                                                                                 |
+| --------------------- | ------------------ | ----------------- | ----------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| 1                     | 24                 | 24                | 24                | One derivation will be built at a time, each one can use 24 cores. Undersold if a job can’t use 24 cores.                                                                                                                                                                              |
+| 4                     | 6                  | 6                 | 24                | Four derivations will be built at once, each given access to six cores.                                                                                                                                                                                                                |
+| 12                    | 6                  | 6                 | 72                | 12 derivations will be built at once, each given access to six cores. This configuration is over-sold. If all 12 derivations being built simultaneously try to use all six cores, the machine's performance will be degraded due to extensive context switching between the 12 builds. |
+| 24                    | 1                  | 1                 | 24                | 24 derivations can build at the same time, each using a single core. Never oversold, but derivations which require many cores will be very slow to compile.                                                                                                                            |
+| 24                    | 0                  | 24                | 576               | 24 derivations can build at the same time, each using all the available cores of the machine. Very likely to be oversold, and very likely to suffer context switches.                                                                                                                  |
+
+It is up to the derivations' build script to respect host's requested
+cores-per-build by following the value of the `NIX_BUILD_CORES`
+environment variable.

doc/manual/src/advanced-topics/diff-hook.md

@@ -0,0 +1,123 @@
+# Verifying Build Reproducibility
+
+You can use Lix's `diff-hook` setting to compare build results. Note
+that this hook is only executed if the results differ; it is not used
+for determining if the results are the same.
+
+For purposes of demonstration, we'll use the following Nix file,
+`deterministic.nix` for testing:
+
+```nix
+let
+  inherit (import <nixpkgs> {}) runCommand;
+in {
+  stable = runCommand "stable" {} ''
+    touch $out
+  '';
+
+  unstable = runCommand "unstable" {} ''
+    echo $RANDOM > $out
+  '';
+}
+```
+
+Additionally, `nix.conf` contains:
+
+    diff-hook = /etc/nix/my-diff-hook
+    run-diff-hook = true
+
+where `/etc/nix/my-diff-hook` is an executable file containing:
+
+```bash
+#!/bin/sh
+exec >&2
+echo "For derivation $3:"
+/run/current-system/sw/bin/diff -r "$1" "$2"
+```
+
+The diff hook is executed by the same user and group who ran the build.
+However, the diff hook does not have write access to the store path just
+built.
+
+# Spot-Checking Build Determinism
+
+Verify a path which already exists in the Nix store by passing `--check`
+to the build command.
+
+If the build passes and is deterministic, Lix will exit with a status
+code of 0:
+
+```console
+$ nix-build ./deterministic.nix --attr stable
+this derivation will be built:
+  /nix/store/z98fasz2jqy9gs0xbvdj939p27jwda38-stable.drv
+building '/nix/store/z98fasz2jqy9gs0xbvdj939p27jwda38-stable.drv'...
+/nix/store/yyxlzw3vqaas7wfp04g0b1xg51f2czgq-stable
+
+$ nix-build ./deterministic.nix --attr stable --check
+checking outputs of '/nix/store/z98fasz2jqy9gs0xbvdj939p27jwda38-stable.drv'...
+/nix/store/yyxlzw3vqaas7wfp04g0b1xg51f2czgq-stable
+```
+
+If the build is not deterministic, Lix will exit with a status code of
+1:
+
+```console
+$ nix-build ./deterministic.nix --attr unstable
+this derivation will be built:
+  /nix/store/cgl13lbj1w368r5z8gywipl1ifli7dhk-unstable.drv
+building '/nix/store/cgl13lbj1w368r5z8gywipl1ifli7dhk-unstable.drv'...
+/nix/store/krpqk0l9ib0ibi1d2w52z293zw455cap-unstable
+
+$ nix-build ./deterministic.nix --attr unstable --check
+checking outputs of '/nix/store/cgl13lbj1w368r5z8gywipl1ifli7dhk-unstable.drv'...
+error: derivation '/nix/store/cgl13lbj1w368r5z8gywipl1ifli7dhk-unstable.drv' may
+not be deterministic: output '/nix/store/krpqk0l9ib0ibi1d2w52z293zw455cap-unstable' differs
+```
+
+In the Lix daemon's log, we will now see:
+
+```
+For derivation /nix/store/cgl13lbj1w368r5z8gywipl1ifli7dhk-unstable.drv:
+1c1
+< 8108
+---
+> 30204
+```
+
+Using `--check` with `--keep-failed` will cause Lix to keep the second
+build's output in a special, `.check` path:
+
+```console
+$ nix-build ./deterministic.nix --attr unstable --check --keep-failed
+checking outputs of '/nix/store/cgl13lbj1w368r5z8gywipl1ifli7dhk-unstable.drv'...
+note: keeping build directory '/tmp/nix-build-unstable.drv-0'
+error: derivation '/nix/store/cgl13lbj1w368r5z8gywipl1ifli7dhk-unstable.drv' may
+not be deterministic: output '/nix/store/krpqk0l9ib0ibi1d2w52z293zw455cap-unstable' differs
+from '/nix/store/krpqk0l9ib0ibi1d2w52z293zw455cap-unstable.check'
+```
+
+In particular, notice the
+`/nix/store/krpqk0l9ib0ibi1d2w52z293zw455cap-unstable.check` output. Lix
+has copied the build results to that directory where you can examine it.
+
+> []{#check-dirs-are-unregistered} **Note**
+>
+> Check paths are not protected against garbage collection, and this
+> path will be deleted on the next garbage collection.
+>
+> The path is guaranteed to be alive for the duration of
+> the `diff-hook`'s execution, but may be deleted any time after.
+>
+> If the comparison is performed as part of automated tooling, please
+> use the diff-hook or author your tooling to handle the case where the
+> build was not deterministic and also a check path does not exist.
+
+`--check` is only usable if the derivation has been built on the system
+already. If the derivation has not been built Lix will fail with the
+error:
+
+    error: some outputs of '/nix/store/hzi1h60z2qf0nb85iwnpvrai3j2w7rr6-unstable.drv'
+    are not valid, so checking is not possible
+
+Run the build without `--check`, and then try with `--check` again.

doc/manual/src/advanced-topics/distributed-builds.md

@@ -0,0 +1,159 @@
+# Remote Builds
+
+Lix supports remote builds, where a local Lix installation can forward
+Nix builds to other machines. This allows multiple builds to be
+performed in parallel and allows Lix to perform multi-platform builds in
+a semi-transparent way. For instance, if you perform a build for a
+`x86_64-darwin` on an `i686-linux` machine, Lix can automatically
+forward the build to a `x86_64-darwin` machine, if available.
+
+To forward a build to a remote machine, it’s required that the remote
+machine is accessible via SSH and that it has Nix installed. You can
+test whether connecting to the remote Nix instance works, e.g.
+
+```console
+$ nix store ping --store ssh://mac
+```
+
+will try to connect to the machine named `mac`. It is possible to
+specify an SSH identity file as part of the remote store URI, e.g.
+
+```console
+$ nix store ping --store ssh://mac?ssh-key=/home/alice/my-key
+```
+
+Since builds should be non-interactive, the key should not have a
+passphrase. Alternatively, you can load identities ahead of time into
+`ssh-agent` or `gpg-agent`.
+
+If you get the error
+
+```console
+bash: nix-store: command not found
+error: cannot connect to 'mac'
+```
+
+then you need to ensure that the `PATH` of non-interactive login shells
+contains Nix.
+
+> **Warning**
+>
+> If you are building via the Lix daemon (default on Linux and macOS), it is the Lix daemon user account (that is, `root`) that should have SSH access to a user (not necessarily `root`) on the remote machine.
+>
+> Furthermore, `root` needs to have the public host keys for the remote system in its `.ssh/known_hosts`.
+> To add them to `known_hosts` for root, do `ssh-keyscan USER@HOST | sudo tee -a ~root/.ssh/known_hosts`.
+>
+> If you can’t or don’t want to configure `root` to be able to access the remote machine, you can use a private Nix store instead by passing e.g. `--store ~/my-nix` when running a Nix command from the local machine.
+
+The list of remote machines can be specified on the command line or in
+the Lix configuration file. The former is convenient for testing. For
+example, the following command allows you to build a derivation for
+`x86_64-darwin` on a Linux machine:
+
+```console
+$ uname
+Linux
+
+$ nix build --impure \
+  --expr '(with import <nixpkgs> { system = "x86_64-darwin"; }; runCommand "foo" {} "uname > $out")' \
+  --builders 'ssh://mac x86_64-darwin'
+[1/0/1 built, 0.0 MiB DL] building foo on ssh://mac
+
+$ cat ./result
+Darwin
+```
+
+It is possible to specify multiple builders separated by a semicolon or
+a newline, e.g.
+
+```console
+  --builders 'ssh://mac x86_64-darwin ; ssh://beastie x86_64-freebsd'
+```
+
+Each machine specification consists of the following elements, separated
+by spaces. Only the first element is required. To leave a field at its
+default, set it to `-`.
+
+1.  The URI of the remote store in the format
+    `ssh://[username@]hostname`, e.g. `ssh://nix@mac` or `ssh://mac`.
+    For backward compatibility, `ssh://` may be omitted. The hostname
+    may be an alias defined in your `~/.ssh/config`.
+
+2.  A comma-separated list of Nix platform type identifiers, such as
+    `x86_64-darwin`. It is possible for a machine to support multiple
+    platform types, e.g., `i686-linux,x86_64-linux`. If omitted, this
+    defaults to the local platform type.
+
+3.  The SSH identity file to be used to log in to the remote machine. If
+    omitted, SSH will use its regular identities.
+
+4.  The maximum number of builds that Lix will execute in parallel on
+    the machine. Typically this should be equal to the number of CPU
+    cores. For instance, the machine `itchy` in the example will execute
+    up to 8 builds in parallel.
+
+5.  The “speed factor”, indicating the relative speed of the machine. If
+    there are multiple machines of the right type, Lix will prefer the
+    fastest, taking load into account.
+
+6.  A comma-separated list of *supported features*. If a derivation has
+    the `requiredSystemFeatures` attribute, then Lix will only perform
+    the derivation on a machine that has the specified features. For
+    instance, the attribute
+
+    ```nix
+    requiredSystemFeatures = [ "kvm" ];
+    ```
+
+    will cause the build to be performed on a machine that has the `kvm`
+    feature.
+
+7.  A comma-separated list of *mandatory features*. A machine will only
+    be used to build a derivation if all of the machine’s mandatory
+    features appear in the derivation’s `requiredSystemFeatures`
+    attribute.
+
+8.  The (base64-encoded) public host key of the remote machine. If omitted, SSH
+    will use its regular known-hosts file. Specifically, the field is calculated
+    via `base64 -w0 /etc/ssh/ssh_host_ed25519_key.pub`.
+
+For example, the machine specification
+
+    nix@scratchy.labs.cs.uu.nl  i686-linux      /home/nix/.ssh/id_scratchy_auto        8 1 kvm
+    nix@itchy.labs.cs.uu.nl     i686-linux      /home/nix/.ssh/id_scratchy_auto        8 2
+    nix@poochie.labs.cs.uu.nl   i686-linux      /home/nix/.ssh/id_scratchy_auto        1 2 kvm benchmark
+
+specifies several machines that can perform `i686-linux` builds.
+However, `poochie` will only do builds that have the attribute
+
+```nix
+requiredSystemFeatures = [ "benchmark" ];
+```
+
+or
+
+```nix
+requiredSystemFeatures = [ "benchmark" "kvm" ];
+```
+
+`itchy` cannot do builds that require `kvm`, but `scratchy` does support
+such builds. For regular builds, `itchy` will be preferred over
+`scratchy` because it has a higher speed factor.
+
+Remote builders can also be configured in `nix.conf`, e.g.
+
+    builders = ssh://mac x86_64-darwin ; ssh://beastie x86_64-freebsd
+
+Finally, remote builders can be configured in a separate configuration
+file included in `builders` via the syntax `@file`. For example,
+
+    builders = @/etc/nix/machines
+
+causes the list of machines in `/etc/nix/machines` to be included. (This
+is the default.)
+
+If you want the builders to use caches, you likely want to set the
+option `builders-use-substitutes` in your local `nix.conf`.
+
+To build only on remote builders and disable building on the local
+machine, you can use the option `--max-jobs 0`.

doc/manual/src/advanced-topics/post-build-hook.md

@@ -0,0 +1,126 @@
+# Using the `post-build-hook`
+
+# Implementation Caveats
+
+Here we use the post-build hook to upload to a binary cache. This is a
+simple and working example, but it is not suitable for all use cases.
+
+The post build hook program runs after each executed build, and blocks
+the build loop. The build loop exits if the hook program fails.
+
+Concretely, this implementation will make Lix slow or unusable when the
+internet is slow or unreliable.
+
+A more advanced implementation might pass the store paths to a
+user-supplied daemon or queue for processing the store paths outside of
+the build loop.
+
+# Prerequisites
+
+This tutorial assumes you have [configured an S3-compatible binary
+cache](../package-management/s3-substituter.md), and that the `root`
+user's default AWS profile can upload to the bucket.
+
+# Set up a Signing Key
+
+Use `nix-store --generate-binary-cache-key` to create our public and
+private signing keys. We will sign paths with the private key, and
+distribute the public key for verifying the authenticity of the paths.
+
+```console
+# nix-store --generate-binary-cache-key example-nix-cache-1 /etc/nix/key.private /etc/nix/key.public
+# cat /etc/nix/key.public
+example-nix-cache-1:1/cKDz3QCCOmwcztD2eV6Coggp6rqc9DGjWv7C0G+rM=
+```
+
+Then update [`nix.conf`](../command-ref/conf-file.md) on any machine that will access the cache.
+Add the cache URL to [`substituters`](../command-ref/conf-file.md#conf-substituters) and the public key to [`trusted-public-keys`](../command-ref/conf-file.md#conf-trusted-public-keys):
+
+    substituters = https://cache.nixos.org/ s3://example-nix-cache
+    trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= example-nix-cache-1:1/cKDz3QCCOmwcztD2eV6Coggp6rqc9DGjWv7C0G+rM=
+
+Machines that build for the cache must sign derivations using the private key.
+On those machines, add the path to the key file to the [`secret-key-files`](../command-ref/conf-file.md#conf-secret-key-files) field in their [`nix.conf`](../command-ref/conf-file.md):
+
+    secret-key-files = /etc/nix/key.private
+
+We will restart the Nix daemon in a later step.
+
+# Implementing the build hook
+
+Write the following script to `/etc/nix/upload-to-cache.sh`:
+
+```bash
+#!/bin/sh
+
+set -eu
+set -f # disable globbing
+export IFS=' '
+
+echo "Uploading paths" $OUT_PATHS
+exec nix copy --to "s3://example-nix-cache" $OUT_PATHS
+```
+
+> **Note**
+>
+> The `$OUT_PATHS` variable is a space-separated list of Nix store
+> paths. In this case, we expect and want the shell to perform word
+> splitting to make each output path its own argument to `nix
+> store sign`. Nix guarantees the paths will not contain any spaces,
+> however a store path might contain glob characters. The `set -f`
+> disables globbing in the shell.
+
+Then make sure the hook program is executable by the `root` user:
+
+```console
+# chmod +x /etc/nix/upload-to-cache.sh
+```
+
+# Updating Lix Configuration
+
+Edit `/etc/nix/nix.conf` to run our hook, by adding the following
+configuration snippet at the end:
+
+    post-build-hook = /etc/nix/upload-to-cache.sh
+
+Then, restart the `nix-daemon`.
+
+# Testing
+
+Build any derivation, for example:
+
+```console
+$ nix-build --expr '(import <nixpkgs> {}).writeText "example" (builtins.toString builtins.currentTime)'
+this derivation will be built:
+  /nix/store/s4pnfbkalzy5qz57qs6yybna8wylkig6-example.drv
+building '/nix/store/s4pnfbkalzy5qz57qs6yybna8wylkig6-example.drv'...
+running post-build-hook '/home/grahamc/projects/github.com/NixOS/nix/post-hook.sh'...
+post-build-hook: Signing paths /nix/store/ibcyipq5gf91838ldx40mjsp0b8w9n18-example
+post-build-hook: Uploading paths /nix/store/ibcyipq5gf91838ldx40mjsp0b8w9n18-example
+/nix/store/ibcyipq5gf91838ldx40mjsp0b8w9n18-example
+```
+
+Then delete the path from the store, and try substituting it from the
+binary cache:
+
+```console
+$ rm ./result
+$ nix-store --delete /nix/store/ibcyipq5gf91838ldx40mjsp0b8w9n18-example
+```
+
+Now, copy the path back from the cache:
+
+```console
+$ nix-store --realise /nix/store/ibcyipq5gf91838ldx40mjsp0b8w9n18-example
+copying path '/nix/store/m8bmqwrch6l3h8s0k3d673xpmipcdpsa-example from 's3://example-nix-cache'...
+warning: you did not specify '--add-root'; the result might be removed by the garbage collector
+/nix/store/m8bmqwrch6l3h8s0k3d673xpmipcdpsa-example
+```
+
+# Conclusion
+
+We now have a Lix installation configured to automatically sign and
+upload every local build to a remote binary cache.
+
+Before deploying this to production, be sure to consider the
+[implementation caveats](#implementation-caveats).

doc/manual/src/architecture/architecture.md

@@ -0,0 +1,114 @@
+# Architecture
+
+This chapter describes how Nix works.
+It should help users understand why Lix behaves as it does, and it should help developers understand how to modify Lix and how to write similar tools.
+
+## Overview
+
+Nix consists of [hierarchical layers].
+
+[hierarchical layers]: https://en.wikipedia.org/wiki/Multitier_architecture#Layers
+
+The following [concept map] shows its main components (rectangles), the objects they operate on (rounded rectangles), and their interactions (connecting phrases):
+
+[concept map]: https://en.wikipedia.org/wiki/Concept_map
+
+```
+
+   .----------------.
+   | Nix expression |----------.
+   '----------------'          |
+           |              passed to
+           |                   |
++----------|-------------------|--------------------------------+
+| Nix impl.|                   V                                |
+| (Lix)    |      +-------------------------+                   |
+|          |      | commmand line interface |------.            |
+|          |      +-------------------------+      |            |
+|          |                   |                   |            |
+|    evaluated by            calls              manages         |
+|          |                   |                   |            |
+|          |                   V                   |            |
+|          |         +--------------------+        |            |
+|          '-------->| language evaluator |        |            |
+|                    +--------------------+        |            |
+|                              |                   |            |
+|                           produces               |            |
+|                              |                   V            |
+| +----------------------------|------------------------------+ |
+| | store                      |                              | |
+| |            referenced by   V       builds                 | |
+| | .-------------.      .------------.      .--------------. | |
+| | | build input |----->| build plan |----->| build result | | |
+| | '-------------'      '------------'      '--------------' | |
+| +-------------------------------------------------|---------+ |
++---------------------------------------------------|-----------+
+                                                    |
+                                              represented as
+                                                    |
+                                                    V
+                                            .---------------.
+                                            |     file      |
+                                            '---------------'
+```
+
+At the top is the [command line interface](../command-ref/command-ref.md) that drives the underlying layers.
+
+The [Nix language](../language/index.md) evaluator transforms Nix expressions into self-contained *build plans*, which are used to derive *build results* from referenced *build inputs*.
+
+The command line interface and Nix expressions are what users deal with most.
+
+> **Note**
+> The Nix language itself does not have a notion of *packages* or *configurations*.
+> As far as we are concerned here, the inputs and results of a build plan are just data.
+
+Underlying the command line interface and the Nix language evaluator is the [Nix store](../glossary.md#gloss-store), a mechanism to keep track of build plans, data, and references between them.
+It can also execute build plans to produce new data, which are made available to the operating system as files.
+
+A build plan itself is a series of *build tasks*, together with their build inputs.
+
+> **Important**
+> A build task in Nix is called [derivation](../glossary.md#gloss-derivation).
+
+Each build task has a special build input executed as *build instructions* in order to perform the build.
+The result of a build task can be input to another build task.
+
+The following [data flow diagram] shows a build plan for illustration.
+Build inputs used as instructions to a build task are marked accordingly:
+
+[data flow diagram]: https://en.wikipedia.org/wiki/Data-flow_diagram
+
+```
++--------------------------------------------------------------------+
+| build plan                                                         |
+|                                                                    |
+| .-------------.                                                    |
+| | build input |---------.                                          |
+| '-------------'         |                                          |
+|                    instructions                                    |
+|                         |                                          |
+|                         v                                          |
+| .-------------.    .----------.                                    |
+| | build input |-->( build task )-------.                           |
+| '-------------'    '----------'        |                           |
+|                                  instructions                      |
+|                                        |                           |
+|                                        v                           |
+| .-------------.                  .----------.     .--------------. |
+| | build input |---------.       ( build task )--->| build result | |
+| '-------------'         |        '----------'     '--------------' |
+|                    instructions        ^                           |
+|                         |              |                           |
+|                         v              |                           |
+| .-------------.    .----------.        |                           |
+| | build input |-->( build task )-------'                           |
+| '-------------'    '----------'                                    |
+|                         ^                                          |
+|                         |                                          |
+|                         |                                          |
+| .-------------.         |                                          |
+| | build input |---------'                                          |
+| '-------------'                                                    |
+|                                                                    |
++--------------------------------------------------------------------+
+```

doc/manual/src/architecture/file-system-object.md

@@ -0,0 +1,64 @@
+# File System Object
+
+Nix implementations use a simplified model of the file system, which consists of file system objects.
+Every file system object is one of the following:
+
+ - File
+
+   - A possibly empty sequence of bytes for contents
+   - A single boolean representing the [executable](https://en.m.wikipedia.org/wiki/File-system_permissions#Permissions) permission
+
+ - Directory
+
+   Mapping of names to child file system objects
+
+ - [Symbolic link](https://en.m.wikipedia.org/wiki/Symbolic_link)
+
+   An arbitrary string.
+   Nix implementations do not assign any semantics to symbolic links.
+
+File system objects and their children form a tree.
+A bare file or symlink can be a root file system object.
+
+Nix does not encode any other file system notions such as [hard links](https://en.m.wikipedia.org/wiki/Hard_link), [permissions](https://en.m.wikipedia.org/wiki/File-system_permissions), timestamps, or other metadata.
+
+## Examples of file system objects
+
+A plain file:
+
+```
+50 B, executable: false
+```
+
+An executable file:
+
+```
+122 KB, executable: true
+```
+
+A symlink:
+
+```
+-> /usr/bin/sh
+```
+
+A directory with contents:
+
+```
+├── bin
+│   └── hello: 35 KB, executable: true
+└── share
+    ├── info
+    │   └── hello.info: 36 KB, executable: false
+    └── man
+        └── man1
+            └── hello.1.gz: 790 B, executable: false
+```
+
+A directory that contains a symlink and other directories:
+
+```
+├── bin -> share/go/bin
+├── nix-support/
+└── share/
+```

doc/manual/src/command-ref/command-ref.md

@@ -0,0 +1,2 @@
+This section lists commands and options that you can use when you work
+with Lix.

doc/manual/src/command-ref/conf-file.md

@@ -0,0 +1,71 @@
+# Name
+
+`nix.conf` - Lix configuration file
+
+# Description
+
+Lix supports a variety of configuration settings, which are read from configuration files or taken as command line flags.
+
+## Configuration file
+
+By default Lix reads settings from the following places, in that order:
+
+1. The system-wide configuration file `sysconfdir/nix/nix.conf` (i.e. `/etc/nix/nix.conf` on most systems), or `$NIX_CONF_DIR/nix.conf` if [`NIX_CONF_DIR`](./env-common.md#env-NIX_CONF_DIR) is set.
+
+   Values loaded in this file are not forwarded to the Nix daemon.
+   The client assumes that the daemon has already loaded them.
+
+1. If [`NIX_USER_CONF_FILES`](./env-common.md#env-NIX_USER_CONF_FILES) is set, then each path separated by `:` will be loaded in reverse order.
+
+   Otherwise it will look for `nix/nix.conf` files in `XDG_CONFIG_DIRS` and `XDG_CONFIG_HOME`.
+   If unset, `XDG_CONFIG_DIRS` defaults to `/etc/xdg`, and `XDG_CONFIG_HOME` defaults to `$HOME/.config` as per [XDG Base Directory Specification](https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html).
+
+1. If [`NIX_CONFIG`](./env-common.md#env-NIX_CONFIG) is set, its contents are treated as the contents of a configuration file.
+
+### File format
+
+Configuration files consist of `name = value` pairs, one per line.
+Comments start with a `#` character.
+
+Example:
+
+```
+keep-outputs = true       # Nice for developers
+keep-derivations = true   # Idem
+```
+
+Other files can be included with a line like `include <path>`, where `<path>` is interpreted relative to the current configuration file.
+A missing file is an error unless `!include` is used instead.
+
+A configuration setting usually overrides any previous value.
+However, for settings that take a list of items, you can prefix the name of the setting by `extra-` to *append* to the previous value.
+
+For instance,
+
+```
+substituters = a b
+extra-substituters = c d
+```
+
+defines the `substituters` setting to be `a b c d`.
+
+Unknown option names are not an error, and are simply ignored with a warning.
+
+## Command line flags
+
+Configuration options can be set on the command line, overriding the values set in the [configuration file](#configuration-file):
+
+- Every configuration setting has corresponding command line flag (e.g. `--max-jobs 16`).
+  Boolean settings do not need an argument, and can be explicitly disabled with the `no-` prefix (e.g. `--keep-failed` and `--no-keep-failed`).
+
+  Unknown option names are invalid flags (unless there is already a flag with that name), and are rejected with an error.
+
+- The flag `--option <name> <value>` is interpreted exactly like a `<name> = <value>` in a setting file.
+
+  Unknown option names are ignored with a warning.
+
+The `extra-` prefix is supported for settings that take a list of items (e.g. `--extra-trusted users alice` or `--option extra-trusted-users alice`).
+
+# Available settings
+
+{{#include @generated@/command-ref/conf-file.md}}

doc/manual/src/command-ref/env-common.md

@@ -0,0 +1,124 @@
+# Common Environment Variables
+
+Most commands in Lix interpret the following environment variables:
+
+  - <span id="env-IN_NIX_SHELL">[`IN_NIX_SHELL`](#env-IN_NIX_SHELL)</span>\
+    Indicator that tells if the current environment was set up by
+    `nix-shell`. It can have the values `pure` or `impure`.
+
+  - <span id="env-NIX_PATH">[`NIX_PATH`](#env-NIX_PATH)</span>\
+    A colon-separated list of directories used to look up the location of Nix
+    expressions using [paths](@docroot@/language/values.md#type-path)
+    enclosed in angle brackets (i.e., `<path>`),
+    e.g. `/home/eelco/Dev:/etc/nixos`. It can be extended using the
+    [`-I` option](@docroot@/command-ref/opt-common.md#opt-I).
+
+    If `NIX_PATH` is not set at all, Lix will fall back to the following list in [impure](@docroot@/command-ref/conf-file.md#conf-pure-eval) and [unrestricted](@docroot@/command-ref/conf-file.md#conf-restrict-eval) evaluation mode:
+
+      1. `$HOME/.nix-defexpr/channels`
+      2. `nixpkgs=/nix/var/nix/profiles/per-user/root/channels/nixpkgs`
+      3. `/nix/var/nix/profiles/per-user/root/channels`
+
+    If `NIX_PATH` is set to an empty string, resolving search paths will always fail.
+    For example, attempting to use `<nixpkgs>` will produce:
+
+        error: file 'nixpkgs' was not found in the Nix search path
+
+  - <span id="env-NIX_IGNORE_SYMLINK_STORE">[`NIX_IGNORE_SYMLINK_STORE`](#env-NIX_IGNORE_SYMLINK_STORE)</span>\
+    Normally, the Nix store directory (typically `/nix/store`) is not
+    allowed to contain any symlink components. This is to prevent
+    “impure” builds. Builders sometimes “canonicalise” paths by
+    resolving all symlink components. Thus, builds on different machines
+    (with `/nix/store` resolving to different locations) could yield
+    different results. This is generally not a problem, except when
+    builds are deployed to machines where `/nix/store` resolves
+    differently. If you are sure that you’re not going to do that, you
+    can set `NIX_IGNORE_SYMLINK_STORE` to `1`.
+
+    Note that if you’re symlinking the Nix store so that you can put it
+    on another file system than the root file system, on Linux you’re
+    better off using `bind` mount points, e.g.,
+
+    ```console
+    $ mkdir /nix
+    $ mount -o bind /mnt/otherdisk/nix /nix
+    ```
+
+    Consult the mount 8 manual page for details.
+
+  - <span id="env-NIX_STORE_DIR">[`NIX_STORE_DIR`](#env-NIX_STORE_DIR)</span>\
+    Overrides the location of the Nix store (default `prefix/store`).
+
+  - <span id="env-NIX_DATA_DIR">[`NIX_DATA_DIR`](#env-NIX_DATA_DIR)</span>\
+    Overrides the location of the Lix static data directory (default
+    `prefix/share`).
+
+  - <span id="env-NIX_LOG_DIR">[`NIX_LOG_DIR`](#env-NIX_LOG_DIR)</span>\
+    Overrides the location of the Lix log directory (default
+    `prefix/var/log/nix`).
+
+  - <span id="env-NIX_STATE_DIR">[`NIX_STATE_DIR`](#env-NIX_STATE_DIR)</span>\
+    Overrides the location of the Lix state directory (default
+    `prefix/var/nix`).
+
+  - <span id="env-NIX_CONF_DIR">[`NIX_CONF_DIR`](#env-NIX_CONF_DIR)</span>\
+    Overrides the location of the system Lix configuration directory
+    (default `prefix/etc/nix`).
+
+  - <span id="env-NIX_CONFIG">[`NIX_CONFIG`](#env-NIX_CONFIG)</span>\
+    Applies settings from Lix configuration from the environment.
+    The content is treated as if it was read from a Lix configuration file.
+    Settings are separated by the newline character.
+
+  - <span id="env-NIX_USER_CONF_FILES">[`NIX_USER_CONF_FILES`](#env-NIX_USER_CONF_FILES)</span>\
+    Overrides the location of the Lix user configuration files to load from.
+
+    The default are the locations according to the [XDG Base Directory Specification].
+    See the [XDG Base Directories](#xdg-base-directories) sub-section for details.
+
+    The variable is treated as a list separated by the `:` token.
+
+  - <span id="env-TMPDIR">[`TMPDIR`](#env-TMPDIR)</span>\
+    Use the specified directory to store temporary files. In particular,
+    this includes temporary build directories; these can take up
+    substantial amounts of disk space. The default is `/tmp`.
+
+  - <span id="env-NIX_REMOTE">[`NIX_REMOTE`](#env-NIX_REMOTE)</span>\
+    This variable should be set to `daemon` if you want to use the Lix
+    daemon to execute Nix operations. This is necessary in [multi-user
+    Nix installations](@docroot@/installation/multi-user.md). If the Lix
+    daemon's Unix socket is at some non-standard path, this variable
+    should be set to `unix://path/to/socket`. Otherwise, it should be
+    left unset.
+
+  - <span id="env-NIX_SHOW_STATS">[`NIX_SHOW_STATS`](#env-NIX_SHOW_STATS)</span>\
+    If set to `1`, Lix will print some evaluation statistics, such as
+    the number of values allocated.
+
+  - <span id="env-NIX_COUNT_CALLS">[`NIX_COUNT_CALLS`](#env-NIX_COUNT_CALLS)</span>\
+    If set to `1`, Lix will print how often functions were called during
+    Nix expression evaluation. This is useful for profiling your Nix
+    expressions.
+
+  - <span id="env-GC_INITIAL_HEAP_SIZE">[`GC_INITIAL_HEAP_SIZE`](#env-GC_INITIAL_HEAP_SIZE)</span>\
+    If Nix has been configured to use the Boehm garbage collector, this
+    variable sets the initial size of the heap in bytes. It defaults to
+    384 MiB. Setting it to a low value reduces memory consumption, but
+    will increase runtime due to the overhead of garbage collection.
+
+## XDG Base Directories
+
+Lix follows the [XDG Base Directory Specification].
+
+For backwards compatibility, commands in Lix will follow the standard only when [`use-xdg-base-directories`] is enabled.
+[New Nix commands](@docroot@/command-ref/new-cli/nix.md) (experimental) conform to the standard by default.
+
+The following environment variables are used to determine locations of various state and configuration files:
+
+- `XDG_CONFIG_HOME` (default `~/.config`)
+- `XDG_STATE_HOME` (default `~/.local/state`)
+- `XDG_CACHE_HOME` (default `~/.cache`)
+
+
+[XDG Base Directory Specification]: https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html
+[`use-xdg-base-directories`]: @docroot@/command-ref/conf-file.md#conf-use-xdg-base-directories

doc/manual/src/command-ref/experimental-commands.md

@@ -0,0 +1,8 @@
+# Experimental Commands
+
+This section lists [experimental commands](@docroot@/contributing/experimental-features.md#xp-feature-nix-command).
+
+> **Warning**
+>
+> These commands may be removed in the future, or their syntax may
+> change in incompatible ways.

doc/manual/src/command-ref/files.md

@@ -0,0 +1,4 @@
+# Files
+
+This section lists configuration files that you can use when you work
+with Lix.

doc/manual/src/command-ref/files/channels.md

@@ -0,0 +1,26 @@
+## Channels
+
+A directory containing symlinks to Nix channels, managed by [`nix-channel`]:
+
+- `$XDG_STATE_HOME/nix/profiles/channels` for regular users
+- `$NIX_STATE_DIR/profiles/per-user/root/channels` for `root`
+
+[`nix-channel`] uses a [profile](@docroot@/command-ref/files/profiles.md) to store channels.
+This profile contains symlinks to the contents of those channels.
+
+## Subscribed channels
+
+The list of subscribed channels is stored in
+
+- `~/.nix-channels`
+- `$XDG_STATE_HOME/nix/channels` if [`use-xdg-base-directories`] is set to `true`
+
+in the following format:
+
+```
+<url> <name>
+...
+```
+
+[`nix-channel`]: @docroot@/command-ref/nix-channel.md
+[`use-xdg-base-directories`]: @docroot@/command-ref/conf-file.md#conf-use-xdg-base-directories

doc/manual/src/command-ref/files/default-nix-expression.md

@@ -0,0 +1,52 @@
+## Default Nix expression
+
+The source for the default [Nix expressions](@docroot@/language/index.md) used by [`nix-env`]:
+
+- `~/.nix-defexpr`
+- `$XDG_STATE_HOME/nix/defexpr` if [`use-xdg-base-directories`] is set to `true`.
+
+It is loaded as follows:
+
+- If the default expression is a file, it is loaded as a Nix expression.
+- If the default expression is a directory containing a `default.nix` file, that `default.nix` file is loaded as a Nix expression.
+- If the default expression is a directory without a `default.nix` file, then its contents (both files and subdirectories) are loaded as Nix expressions.
+  The expressions are combined into a single attribute set, each expression under an attribute with the same name as the original file or subdirectory.
+  Subdirectories without a `default.nix` file are traversed recursively in search of more Nix expressions, but the names of these intermediate directories are not added to the attribute paths of the default Nix expression.
+
+Then, the resulting expression is interpreted like this:
+
+- If the expression is an attribute set, it is used as the default Nix expression.
+- If the expression is a function, an empty set is passed as argument and the return value is used as the default Nix expression.
+
+
+For example, if the default expression contains two files, `foo.nix` and `bar.nix`, then the default Nix expression will be equivalent to
+
+```nix
+{
+  foo = import ~/.nix-defexpr/foo.nix;
+  bar = import ~/.nix-defexpr/bar.nix;
+}
+```
+
+The file [`manifest.nix`](@docroot@/command-ref/files/manifest.nix.md) is always ignored.
+
+The command [`nix-channel`] places a symlink to the user's current [channels profile](@docroot@/command-ref/files/channels.md) in this directory.
+This makes all subscribed channels available as attributes in the default expression.
+
+## User channel link
+
+A symlink that ensures that [`nix-env`] can find your channels:
+
+- `~/.nix-defexpr/channels`
+- `$XDG_STATE_HOME/defexpr/channels` if [`use-xdg-base-directories`] is set to `true`.
+
+This symlink points to:
+
+- `$XDG_STATE_HOME/profiles/channels` for regular users
+- `$NIX_STATE_DIR/profiles/per-user/root/channels` for `root`
+
+In a multi-user installation, you may also have `~/.nix-defexpr/channels_root`, which links to the channels of the root user.[`nix-env`]: ../nix-env.md
+
+[`nix-env`]: @docroot@/command-ref/nix-env.md
+[`nix-channel`]: @docroot@/command-ref/nix-channel.md
+[`use-xdg-base-directories`]: @docroot@/command-ref/conf-file.md#conf-use-xdg-base-directories

doc/manual/src/command-ref/files/manifest.json.md

@@ -0,0 +1,45 @@
+## `manifest.json`
+
+The manifest file records the provenance of the packages that are installed in a [profile](./profiles.md) managed by [`nix profile`](@docroot@/command-ref/new-cli/nix3-profile.md) (experimental).
+
+Here is an example of what the file might look like after installing `zoom-us` from Nixpkgs:
+
+```json
+{
+  "version": 1,
+  "elements": [
+    {
+      "active": true,
+      "attrPath": "legacyPackages.x86_64-linux.zoom-us",
+      "originalUrl": "flake:nixpkgs",
+      "storePaths": [
+        "/nix/store/wbhg2ga8f3h87s9h5k0slxk0m81m4cxl-zoom-us-5.3.469451.0927"
+      ],
+      "uri": "github:NixOS/nixpkgs/13d0c311e3ae923a00f734b43fd1d35b47d8943a"
+    },
+    …
+  ]
+}
+```
+
+Each object in the array `elements` denotes an installed package and
+has the following fields:
+
+* `originalUrl`: The [flake reference](@docroot@/command-ref/new-cli/nix3-flake.md) specified by
+  the user at the time of installation (e.g. `nixpkgs`). This is also
+  the flake reference that will be used by `nix profile upgrade`.
+
+* `uri`: The locked flake reference to which `originalUrl` resolved.
+
+* `attrPath`: The flake output attribute that provided this
+  package. Note that this is not necessarily the attribute that the
+  user specified, but the one resulting from applying the default
+  attribute paths and prefixes; for instance, `hello` might resolve to
+  `packages.x86_64-linux.hello` and the empty string to
+  `packages.x86_64-linux.default`.
+
+* `storePath`: The paths in the Nix store containing the package.
+
+* `active`: Whether the profile contains symlinks to the files of this
+  package. If set to false, the package is kept in the Nix store, but
+  is not "visible" in the profile's symlink tree.

doc/manual/src/command-ref/files/manifest.nix.md

@@ -0,0 +1,128 @@
+## `manifest.nix`
+
+The manifest file records the provenance of the packages that are installed in a [profile](./profiles.md) managed by [`nix-env`](@docroot@/command-ref/nix-env.md).
+
+Here is an example of how this file might look like after installing `hello` from Nixpkgs:
+
+```nix
+[{
+  meta = {
+    available = true;
+    broken = false;
+    changelog =
+      "https://git.savannah.gnu.org/cgit/hello.git/plain/NEWS?h=v2.12.1";
+    description = "A program that produces a familiar, friendly greeting";
+    homepage = "https://www.gnu.org/software/hello/manual/";
+    insecure = false;
+    license = {
+      deprecated = false;
+      free = true;
+      fullName = "GNU General Public License v3.0 or later";
+      redistributable = true;
+      shortName = "gpl3Plus";
+      spdxId = "GPL-3.0-or-later";
+      url = "https://spdx.org/licenses/GPL-3.0-or-later.html";
+    };
+    longDescription = ''
+      GNU Hello is a program that prints "Hello, world!" when you run it.
+      It is fully customizable.
+    '';
+    maintainers = [{
+      email = "edolstra+nixpkgs@gmail.com";
+      github = "edolstra";
+      githubId = 1148549;
+      name = "Eelco Dolstra";
+    }];
+    name = "hello-2.12.1";
+    outputsToInstall = [ "out" ];
+    platforms = [
+      "i686-cygwin"
+      "x86_64-cygwin"
+      "x86_64-darwin"
+      "i686-darwin"
+      "aarch64-darwin"
+      "armv7a-darwin"
+      "i686-freebsd13"
+      "x86_64-freebsd13"
+      "aarch64-genode"
+      "i686-genode"
+      "x86_64-genode"
+      "x86_64-solaris"
+      "js-ghcjs"
+      "aarch64-linux"
+      "armv5tel-linux"
+      "armv6l-linux"
+      "armv7a-linux"
+      "armv7l-linux"
+      "i686-linux"
+      "m68k-linux"
+      "microblaze-linux"
+      "microblazeel-linux"
+      "mipsel-linux"
+      "mips64el-linux"
+      "powerpc64-linux"
+      "powerpc64le-linux"
+      "riscv32-linux"
+      "riscv64-linux"
+      "s390-linux"
+      "s390x-linux"
+      "x86_64-linux"
+      "mmix-mmixware"
+      "aarch64-netbsd"
+      "armv6l-netbsd"
+      "armv7a-netbsd"
+      "armv7l-netbsd"
+      "i686-netbsd"
+      "m68k-netbsd"
+      "mipsel-netbsd"
+      "powerpc-netbsd"
+      "riscv32-netbsd"
+      "riscv64-netbsd"
+      "x86_64-netbsd"
+      "aarch64_be-none"
+      "aarch64-none"
+      "arm-none"
+      "armv6l-none"
+      "avr-none"
+      "i686-none"
+      "microblaze-none"
+      "microblazeel-none"
+      "msp430-none"
+      "or1k-none"
+      "m68k-none"
+      "powerpc-none"
+      "powerpcle-none"
+      "riscv32-none"
+      "riscv64-none"
+      "rx-none"
+      "s390-none"
+      "s390x-none"
+      "vc4-none"
+      "x86_64-none"
+      "i686-openbsd"
+      "x86_64-openbsd"
+      "x86_64-redox"
+      "wasm64-wasi"
+      "wasm32-wasi"
+      "x86_64-windows"
+      "i686-windows"
+    ];
+    position =
+      "/nix/store/7niq32w715567hbph0q13m5lqna64c1s-nixos-unstable.tar.gz/nixos-unstable.tar.gz/pkgs/applications/misc/hello/default.nix:34";
+    unfree = false;
+    unsupported = false;
+  };
+  name = "hello-2.12.1";
+  out = {
+    outPath = "/nix/store/260q5867crm1xjs4khgqpl6vr9kywql1-hello-2.12.1";
+  };
+  outPath = "/nix/store/260q5867crm1xjs4khgqpl6vr9kywql1-hello-2.12.1";
+  outputs = [ "out" ];
+  system = "x86_64-linux";
+  type = "derivation";
+}]
+```
+
+Each element in this list corresponds to an installed package.
+It incorporates some attributes of the original derivation, including `meta`, `name`, `out`, `outPath`, `outputs`, `system`.
+This information is used by Nix for querying and updating the package.

doc/manual/src/command-ref/files/profiles.md

@@ -0,0 +1,74 @@
+## Profiles
+
+A directory that contains links to profiles managed by [`nix-env`] and [`nix profile`]:
+
+- `$XDG_STATE_HOME/nix/profiles` for regular users
+- `$NIX_STATE_DIR/profiles/per-user/root` if the user is `root`
+
+A profile is a directory of symlinks to files in the Nix store.
+
+### Filesystem layout
+
+Profiles are versioned as follows. When using a profile named *path*, *path* is a symlink to *path*`-`*N*`-link`, where *N* is the version of the profile.
+In turn, *path*`-`*N*`-link` is a symlink to a path in the Nix store.
+For example:
+
+```console
+$ ls -l ~alice/.local/state/nix/profiles/profile*
+lrwxrwxrwx 1 alice users 14 Nov 25 14:35 /home/alice/.local/state/nix/profiles/profile -> profile-7-link
+lrwxrwxrwx 1 alice users 51 Oct 28 16:18 /home/alice/.local/state/nix/profiles/profile-5-link -> /nix/store/q69xad13ghpf7ir87h0b2gd28lafjj1j-profile
+lrwxrwxrwx 1 alice users 51 Oct 29 13:20 /home/alice/.local/state/nix/profiles/profile-6-link -> /nix/store/6bvhpysd7vwz7k3b0pndn7ifi5xr32dg-profile
+lrwxrwxrwx 1 alice users 51 Nov 25 14:35 /home/alice/.local/state/nix/profiles/profile-7-link -> /nix/store/mp0x6xnsg0b8qhswy6riqvimai4gm677-profile
+```
+
+Each of these symlinks is a root for the Lix garbage collector.
+
+The contents of the store path corresponding to each version of the
+profile is a tree of symlinks to the files of the installed packages,
+e.g.
+
+```console
+$ ll -R ~eelco/.local/state/nix/profiles/profile-7-link/
+/home/eelco/.local/state/nix/profiles/profile-7-link/:
+total 20
+dr-xr-xr-x 2 root root 4096 Jan  1  1970 bin
+-r--r--r-- 2 root root 1402 Jan  1  1970 manifest.nix
+dr-xr-xr-x 4 root root 4096 Jan  1  1970 share
+
+/home/eelco/.local/state/nix/profiles/profile-7-link/bin:
+total 20
+lrwxrwxrwx 5 root root 79 Jan  1  1970 chromium -> /nix/store/ijm5k0zqisvkdwjkc77mb9qzb35xfi4m-chromium-86.0.4240.111/bin/chromium
+lrwxrwxrwx 7 root root 87 Jan  1  1970 spotify -> /nix/store/w9182874m1bl56smps3m5zjj36jhp3rn-spotify-1.1.26.501.gbe11e53b-15/bin/spotify
+lrwxrwxrwx 3 root root 79 Jan  1  1970 zoom-us -> /nix/store/wbhg2ga8f3h87s9h5k0slxk0m81m4cxl-zoom-us-5.3.469451.0927/bin/zoom-us
+
+/home/eelco/.local/state/nix/profiles/profile-7-link/share/applications:
+total 12
+lrwxrwxrwx 4 root root 120 Jan  1  1970 chromium-browser.desktop -> /nix/store/4cf803y4vzfm3gyk3vzhzb2327v0kl8a-chromium-unwrapped-86.0.4240.111/share/applications/chromium-browser.desktop
+lrwxrwxrwx 7 root root 110 Jan  1  1970 spotify.desktop -> /nix/store/w9182874m1bl56smps3m5zjj36jhp3rn-spotify-1.1.26.501.gbe11e53b-15/share/applications/spotify.desktop
+lrwxrwxrwx 3 root root 107 Jan  1  1970 us.zoom.Zoom.desktop -> /nix/store/wbhg2ga8f3h87s9h5k0slxk0m81m4cxl-zoom-us-5.3.469451.0927/share/applications/us.zoom.Zoom.desktop
+
+…
+```
+
+Each profile version contains a manifest file:
+- [`manifest.nix`](@docroot@/command-ref/files/manifest.nix.md) used by [`nix-env`](@docroot@/command-ref/nix-env.md).
+- [`manifest.json`](@docroot@/command-ref/files/manifest.json.md) used by [`nix profile`](@docroot@/command-ref/new-cli/nix3-profile.md) (experimental).
+
+## User profile link
+
+A symbolic link to the user's current profile:
+
+- `~/.nix-profile`
+- `$XDG_STATE_HOME/nix/profile` if [`use-xdg-base-directories`] is set to `true`.
+
+By default, this symlink points to:
+
+- `$XDG_STATE_HOME/nix/profiles/profile` for regular users
+- `$NIX_STATE_DIR/profiles/per-user/root/profile` for `root`
+
+The `PATH` environment variable should include `/bin` subdirectory of the profile link (e.g. `~/.nix-profile/bin`) for the user environment to be visible to the user.
+The [installer](@docroot@/installation/installing-binary.md) sets this up by default, unless you enable [`use-xdg-base-directories`].
+
+[`nix-env`]: @docroot@/command-ref/nix-env.md
+[`nix profile`]: @docroot@/command-ref/new-cli/nix3-profile.md
+[`use-xdg-base-directories`]: @docroot@/command-ref/conf-file.md#conf-use-xdg-base-directories

doc/manual/src/command-ref/main-commands.md

@@ -0,0 +1,4 @@
+# Main Commands
+
+This section lists commands and options that you can use when you work
+with Lix.

doc/manual/src/command-ref/meson.build

@@ -0,0 +1,66 @@
+xp_features_json = custom_target(
+  command : [nix, '__dump-xp-features'],
+  capture : true,
+  output : 'xp-features.json',
+)
+
+experimental_features_shortlist_md = custom_target(
+  command : nix_eval_for_docs + [
+    '--expr',
+    'import @INPUT0@ (builtins.fromJSON (builtins.readFile @INPUT1@))',
+  ],
+  input : [
+    '../../generate-xp-features-shortlist.nix',
+    xp_features_json,
+  ],
+  capture : true,
+  output : 'experimental-features-shortlist.md',
+  env : nix_env_for_docs,
+)
+
+# Intermediate step for manpage generation.
+# This splorks the output of generate-manpage.nix as JSON,
+# which gets written as a directory tree below.
+nix3_cli_files_json = custom_target(
+  command : nix_eval_for_docs_common + [
+    '--json',
+    '--expr',
+    'import @INPUT0@ true (builtins.readFile @INPUT1@)',
+  ],
+  input : [
+    '../../generate-manpage.nix',
+    nix3_cli_json,
+  ],
+  capture : true,
+  output : 'new-cli.json',
+  env : nix_env_for_docs,
+)
+nix3_cli_files = custom_target(
+  command : [
+    python,
+    '@INPUT0@',
+    '-i', '@INPUT1@',
+    '-o', '@OUTPUT@',
+  ],
+  input : [
+    '../../json-to-tree.py',
+    nix3_cli_files_json,
+  ],
+  output : 'new-cli',
+)
+
+conf_file_md = custom_target(
+  command : [
+    nix_eval_for_docs,
+    '--expr',
+    '(import @INPUT0@).showSettings { inlineHTML = true; } (builtins.fromJSON (builtins.readFile @INPUT1@))',
+  ],
+  capture : true,
+  input : [
+    '../../utils.nix',
+    conf_file_json,
+    experimental_features_shortlist_md,
+  ],
+  output : 'conf-file.md',
+  env : nix_env_for_docs,
+)

doc/manual/src/command-ref/new-cli/nix.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix.md}}

doc/manual/src/command-ref/new-cli/nix3-build.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-build.md}}

doc/manual/src/command-ref/new-cli/nix3-bundle.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-bundle.md}}

doc/manual/src/command-ref/new-cli/nix3-config-show.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-config-show.md}}

doc/manual/src/command-ref/new-cli/nix3-config.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-config.md}}

doc/manual/src/command-ref/new-cli/nix3-copy.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-copy.md}}

doc/manual/src/command-ref/new-cli/nix3-daemon.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-daemon.md}}

doc/manual/src/command-ref/new-cli/nix3-derivation-add.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-derivation-add.md}}

doc/manual/src/command-ref/new-cli/nix3-derivation-show.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-derivation-show.md}}

doc/manual/src/command-ref/new-cli/nix3-derivation.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-derivation.md}}

doc/manual/src/command-ref/new-cli/nix3-develop.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-develop.md}}

doc/manual/src/command-ref/new-cli/nix3-doctor.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-doctor.md}}

doc/manual/src/command-ref/new-cli/nix3-edit.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-edit.md}}

doc/manual/src/command-ref/new-cli/nix3-eval.md

@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-eval.md}}