release: 2.90.0 "Vanilla Ice Cream"

Release produced with releng/create_release.xsh Change-Id: Ice53891cdeafff04bd6537be66e8cd6b7dd9678c
doc/release-notes: add date for major release
2024-07-10 08:40:42 -07:00 · 2024-07-10 15:35:00 +00:00 · 2024-07-10 15:32:19 +02:00 · 2024-06-16 19:06:45 -07:00
2415 changed files with 59309 additions and 99484 deletions
@@ -16,27 +16,3 @@ Checks:
  - -bugprone-unchecked-optional-access
    # many warnings, seems like a questionable lint
  - -bugprone-branch-clone
-    # extremely noisy before clang 19: https://github.com/llvm/llvm-project/issues/93959
-  - -bugprone-multi-level-implicit-pointer-conversion
-    # we don't compile out our asserts
-  - -bugprone-assert-side-effect
-    # FIXME(jade): figure out if this warning is any good
-  - -bugprone-exception-escape
-    # all thrown exceptions must derive from std::exception
-  - hicpp-exception-baseclass
-    # capturing async lambdas are dangerous
-  - cppcoreguidelines-avoid-capturing-lambda-coroutines
-    # crimes must be appropriately declared as crimes
-  - cppcoreguidelines-pro-type-cstyle-cast
-  - lix-*
-    # This can not yet be applied to Lix itself since we need to do source
-    # reorganization so that lix/ include paths work.
-  - -lix-fixincludes
-    # This lint is included as an example, but the lib function it replaces is
-    # already gone.
-  - -lix-hasprefixsuffix
-
-
-CheckOptions:
-  bugprone-reserved-identifier.AllowedIdentifiers: '__asan_default_options'
-  bugprone-unused-return-value.AllowCastToVoid: true
@@ -29,11 +29,3 @@ trim_trailing_whitespace = false
 indent_style = space
 indent_size = 2
 max_line_length = 0
-
-[meson.build]
-indent_style = space
-indent_size = 2
-
-[*.json]
-indent_style = space
-indent_size = 4
@@ -1,5 +1,9 @@
 # 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[@]}"
+# TODO: `use flake .#native-clangStdenvPackages` on macOS?
+use flake ".#${LIX_SHELL_VARIANT:-default}" "${LIX_SHELL_EXTRA_ARGS[@]}"
+export MAKEFLAGS="$MAKEFLAGS -e"
+if [[ -n "$NIX_BUILD_CORES" ]]; then
+    export MAKEFLAGS="$MAKEFLAGS -j $NIX_BUILD_CORES"
+fi
 export GTEST_BRIEF=1
@@ -2,7 +2,7 @@
 name: Missing or incorrect documentation
 about: Help us improve the reference manual
 title: ''
-labels: docs
+labels: documentation
 assignees: ''

 ---
@@ -19,10 +19,10 @@ assignees: ''

 <!-- make sure this issue is not redundant or obsolete -->

- [ ] checked [latest Lix manual] or its [source code]
+- [ ] checked [latest Lix manual] \([source]\)
 - [ ] checked [documentation issues] and [recent documentation changes] for possible duplicates

-[latest Lix manual]: https://docs.lix.systems/manual/lix/nightly
-[source code]: https://git.lix.systems/lix-project/lix/src/main/doc/manual/src
+[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
@@ -9,10 +9,6 @@ GTAGS
 # ccls
 /.ccls-cache

-# auto-generated compilation database
-compile_commands.json
-rust-project.json
-
 result
 result-*

@@ -33,11 +29,3 @@ buildtime.bin
 /.pre-commit-config.yaml
 /.nocontribmsg
 /release
-
-# Rust build files when using Cargo (not actually supported for building but it spews the files anyway)
-/target/
-
-# Python compiled files from the code generators and test suite
-*.pyc
-
-**/.idea
@@ -1,2 +0,0 @@
-Fiona Behrens <me@kloenk.dev>
-Fiona Behrens <me@kloenk.dev> <me@kloenk.de>
@@ -1 +0,0 @@
-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.
@@ -1,79 +0,0 @@
-# This file is automatically @generated by Cargo.
-# It is not intended for manual editing.
-version = 4
-
-[[package]]
-name = "countme"
-version = "3.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7704b5fdd17b18ae31c4c1da5a2e0305a2bf17b5249300a9ee9ed7b72114c636"
-
-[[package]]
-name = "dissimilar"
-version = "1.0.9"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "59f8e79d1fbf76bdfbde321e902714bf6c49df88a7dda6fc682fc2979226962d"
-
-[[package]]
-name = "expect-test"
-version = "1.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9e0be0a561335815e06dab7c62e50353134c796e7a6155402a64bcff66b6a5e0"
-dependencies = [
- "dissimilar",
- "once_cell",
-]
-
-[[package]]
-name = "hashbrown"
-version = "0.14.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5274423e17b7c9fc20b6e7e208532f9b19825d82dfd615708b70edd83df41f1"
-
-[[package]]
-name = "lix-doc"
-version = "0.0.1"
-dependencies = [
- "expect-test",
- "rnix",
- "rowan",
-]
-
-[[package]]
-name = "once_cell"
-version = "1.19.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3fdb12b2476b595f9358c5161aa467c2438859caa136dec86c26fdd2efe17b92"
-
-[[package]]
-name = "rnix"
-version = "0.12.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6f15e00b0ab43abd70d50b6f8cd021290028f9b7fdd7cdfa6c35997173bc1ba9"
-dependencies = [
- "rowan",
-]
-
-[[package]]
-name = "rowan"
-version = "0.15.16"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0a542b0253fa46e632d27a1dc5cf7b930de4df8659dc6e720b647fc72147ae3d"
-dependencies = [
- "countme",
- "hashbrown",
- "rustc-hash",
- "text-size",
-]
-
-[[package]]
-name = "rustc-hash"
-version = "1.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
-
-[[package]]
-name = "text-size"
-version = "1.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f18aa187839b2bdb1ad2fa35ead8c4c2976b64e4363c386d45ac0f7ee85c9233"
@@ -1,6 +0,0 @@
-[workspace]
-resolver = "2"
-members = ["lix/lix-doc"]
-
-[workspace.package]
-edition = "2021"
@@ -1,26 +0,0 @@
-# Docs
-per-file README.md=*
-per-file CONTRIBUTING.md=*
-
-# DevX
-per-file justfile=*
-per-file .envrc=*
-per-file .gitignore=*
-per-file .github=*
-per-file .mailmap=*
-
-# Build
-per-file meson.build=*
-per-file meson.options=*
-per-file flake.nix=*
-per-file flake.lock=*
-per-file *.nix=*
-per-file Cargo.lock=*
-per-file Cargo.toml=*
-per-file version.json=*
-
-# Code style
-per-file .clang-tidy=*
-per-file .clang-format=*
-per-file .editorconfig=*
-per-file treefmt.toml=*
@@ -17,16 +17,13 @@ For systems that **already have a Nix implementation installed**, such as NixOS

 ## 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 set up a development environment and build Lix from source.
+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

- The Lix reference manual:
-  - [Stable](https://docs.lix.systems/manual/lix/stable/)
-  - [Nightly](https://docs.lix.systems/manual/lix/nightly/) (NOTE: [not automatically updated, yet](https://git.lix.systems/lix-project/lix/issues/742))
 - [Our wiki](https://wiki.lix.systems)
 - [Matrix - #space:lix.systems](https://matrix.to/#/#space:lix.systems)

 ## License

-Lix is released under [LGPL-2.1-or-later](./COPYING).
+Lix is released under the [LGPL v2.1](./COPYING).
@@ -1,4 +1,3 @@
 bench-*.json
 bench-*.md
-perf-*.json
 nixpkgs
@@ -1 +0,0 @@
-*
@@ -1,237 +0,0 @@
-#!/usr/bin/env nix-shell
-#!nix-shell -i python3 -p python3 -p hyperfine -p "if stdenv.isLinux then linuxPackages.perf else null"
-
-import argparse
-import subprocess
-import os
-import json
-import tempfile
-import platform
-import shlex
-import textwrap
-import dataclasses
-
-flake_args = ["--extra-experimental-features", "nix-command flakes"]
-cases = {
-    "search": lambda build: [
-        f"{build}/bin/nix",
-        *flake_args,
-        "search",
-        "--no-eval-cache",
-        "github:nixos/nixpkgs/e1fa12d4f6c6fe19ccb59cac54b5b3f25e160870",
-        "hello",
-    ],
-    "rebuild": lambda build: [
-        f"{build}/bin/nix",
-        *flake_args,
-        "eval",
-        "--raw",
-        "--impure",
-        "--expr",
-        textwrap.dedent("""
-            (import <nixpkgs/nixos> {
-                configuration = ./bench/nixpkgs/nixos/modules/installer/cd-dvd/installation-cd-graphical-calamares-plasma6.nix;
-            }).config.system.build.toplevel
-        """).replace("\n", " "),
-    ],
-    "rebuild_lh": lambda build: [
-        "GC_INITIAL_HEAP_SIZE=10g",
-        *cases['rebuild'](build),
-    ],
-    "parse": lambda build: [
-        f"{build}/bin/nix",
-        *flake_args,
-        "eval",
-        "-f",
-        "bench/nixpkgs/pkgs/development/haskell-modules/hackage-packages.nix",
-    ],
-}
-
-arg_parser = argparse.ArgumentParser()
-# FIXME(jade, gilice): 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.
-arg_parser.add_argument(
-    'builds',
-    nargs='+',
-    help="At least two build directories to compare, containing bin/nix",
-)
-arg_parser.add_argument(
-    '--cases',
-    type=str,
-    help="A comma-separated list of cases you want to run. Defaults to running all",
-)
-arg_parser.add_argument(
-    '--mode',
-    nargs='+',
-    choices=[ "walltime", "memory" ] + [ "icount" ] if platform.system() == 'Linux' else [], # perf doesn't run on Darwin
-    default=[ "walltime" ],
-)
-arg_parser.add_argument(
-    '--daemon',
-    action='store_true',
-    help='Run a temporary daemon for the benchmark instead of using a local store directly',
-)
-args = arg_parser.parse_args()
-if len(args.builds) < 1:
-    raise ValueError("need at least one build directory to benchmark")
-
-benchmarks: list[str] = []
-if args.cases is None:
-    benchmarks = list(cases.keys())
-else:
-    for case in args.cases.split(","):
-        if case not in cases:
-            raise ValueError(f"no such case: {case}")
-        benchmarks.append(case)
-
-def make_full_command(build, case):
-    cmd = " ".join(map(shlex.quote, cases[case](build)))
-    if args.daemon:
-        return " ".join([
-            f"{build}/bin/nix --extra-experimental-features nix-command daemon &",
-            "trap 'kill %1' EXIT;",
-            f"NIX_REMOTE=daemon {cmd}",
-        ])
-    else:
-        return cmd
-
-def bench_walltime(env):
-    for case in benchmarks:
-        for build in args.builds:
-            subprocess.run([
-                "taskset", "-c", "2,3",
-                "chrt", "-f","50",
-                *[
-                    "hyperfine", "--warmup", "2", "--runs", "10",
-                    "--export-json", f"bench/bench-{case}-{build}.json",
-                    "--export-markdown", f"bench/bench-{case}-{build}.md",
-                    "--", make_full_command(build, case),
-                ],
-            ], env=env, check=True)
-
-    print("Benchmarks summary\n---\n")
-    for case in benchmarks:
-        results = []
-        for build in args.builds:
-            with open(f"bench/bench-{case}-{build}.json") as fd:
-                results.append(json.load(fd)["results"][0])
-        for result in results:
-            print(result["command"])
-            print("-" * min(80,len(result["command"])))
-            def attr_rounded(attr):
-                return f"{result[attr]:.3f}"
-            print("  mean:    ", attr_rounded("mean"), "±", attr_rounded("stddev"))
-            print("            user:",  attr_rounded("user"), "| system", attr_rounded("system"))
-            print("  median:  ", attr_rounded("median"))
-            print("  range:   ", attr_rounded("min") + "s.." + attr_rounded("max")+"s")
-            print("  relative:", f"{result["mean"]/results[0]["mean"]:.3f}")
-            print("\n")
-
-
-def bench_icount(env):
-    perf_results_for: dict[str, list[tuple[str, float]]] = {}
-    for case in benchmarks:
-        for build in args.builds:
-            # the perf stat -j output (incorrectly) localizes numbers, which will trip up the json parser.
-            env["LC_ALL"]="C"
-            case_command = make_full_command(build, case)
-            commandline = [
-                "perf", "stat", "-o", f"bench/perf-{case}.json", "-j",
-                "sh", "-c", case_command,
-            ]
-            print("running", case_command)
-            subprocess.run(commandline, env=env, check=True, stdout=subprocess.DEVNULL) # warmup run
-            subprocess.run(commandline, env=env, check=True, stdout=subprocess.DEVNULL)
-            perf_fd = open(f"bench/perf-{case}.json")
-            perf_data = [json.loads(x) for x in perf_fd.readlines()]
-            perf_fd.close()
-
-            instr = next(x for x in perf_data if x["event"] in ["instructions", "instructions:u"]) # an implementation of a find_first iterator
-            if case not in perf_results_for:
-                perf_results_for[case] = []
-            perf_results_for[case].append((case_command, float(instr["counter-value"])))
-
-    print("Benchmarks summary\n---\n")
-    for (case, entries) in perf_results_for.items():
-        for entry in entries:
-            cmd,instr = entry
-            print(cmd)
-            print("-" * min(80,len(cmd)))
-            print("  instructions:         ", int(instr))
-            print("  relative instructions:", int(instr)/perf_results_for[case][0][1])
-            print("\n")
-
-@dataclasses.dataclass
-class MemoryStatistics:
-    envBytes: int
-    listBytes: int
-    setBytes: int
-    valueBytes: int
-    heapBytes: int
-    heapSize: int
-
-def bench_memory(env):
-    path = "bench/bench-memory.json"
-    env = env | {
-        'NIX_SHOW_STATS': '1',
-        'NIX_SHOW_STATS_PATH': path,
-    }
-    results: dict[str, list[tuple[str, MemoryStatistics]]] = {}
-    for case in benchmarks:
-        for build in args.builds:
-            case_command = make_full_command(build, case)
-            commandline = [ "sh", "-c", case_command ]
-            print("running", case_command)
-            subprocess.run(commandline, env=env, check=True, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
-            with open(path) as fd:
-                stats = json.load(fd)
-            results.setdefault(case, []).append((case_command, MemoryStatistics(
-                envBytes=stats['envs']['bytes'],
-                listBytes=stats['list']['bytes'],
-                setBytes=stats['sets']['bytes'],
-                valueBytes=stats['values']['bytes'],
-                heapSize=stats['gc']['heapSize'],
-                heapBytes=stats['gc']['totalBytes'],
-            )))
-
-    print("Benchmarks summary\n---\n")
-    for (case, entries) in results.items():
-        for cmd, stats in entries:
-            print(cmd)
-            print("-" * min(80, len(cmd)))
-            print(f"  env bytes:    {stats.envBytes  :15d}   |  {(stats.envBytes / entries[0][1].envBytes)    :.3f}x")
-            print(f"  list bytes:   {stats.listBytes :15d}   |  {(stats.listBytes / entries[0][1].listBytes)  :.3f}x")
-            print(f"  set bytes:    {stats.setBytes  :15d}   |  {(stats.setBytes / entries[0][1].setBytes)    :.3f}x")
-            if not entries[0][1].valueBytes:
-                print(f"  value bytes:  {0:15d}")
-            else:
-                print(f"  value bytes:  {stats.valueBytes:15d}   |  {(stats.valueBytes / entries[0][1].valueBytes):.3f}x")
-            print(f"  heap alloc'd: {stats.heapBytes :15d}   |  {(stats.heapBytes / entries[0][1].heapBytes)  :.3f}x")
-            print(f"  heap size:    {stats.heapSize  :15d}   |  {(stats.heapSize / entries[0][1].heapSize)    :.3f}x")
-            print("\n")
-
-with tempfile.TemporaryDirectory() as tmp_dir:
-    subprocess.run([
-        "nix", "build",
-        "--extra-experimental-features", "nix-command flakes",
-        "--impure", "--expr",'(builtins.getFlake "git+file:.").inputs.nixpkgs.outPath',
-        "-o","bench/nixpkgs"
-    ], check=True)
-    subenv = os.environ.copy()
-    subenv["NIX_CONF_DIR"] = "/var/empty"
-    subenv["NIX_REMOTE"] = tmp_dir
-    subenv["NIX_PATH"] = ":".join([
-        "nixpkgs=bench/nixpkgs",
-    ])
-    subenv["NIX_DAEMON_SOCKET_PATH"] = f"{tmp_dir}/daemon"
-
-    for mode in args.mode:
-        if mode == "walltime":
-            bench_walltime(subenv)
-        elif mode == "memory":
-            bench_memory(subenv)
-        else:
-            bench_icount(subenv)
@@ -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
@@ -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 ${pkgs.python3}/bin/python
+    '';
+    serviceConfig = {
+      CapabilityBoundingSet = [ "" ];
+      KeyringMode = "private";
+      LockPersonality = true;
+      MemoryDenyWriteExecute = true;
+      NoNewPrivileges = true;
+      PrivateDevices = true;
+      PrivateTmp = true;
+      PrivateUsers = true;
+      ProcSubset = "pid";
+      ProtectClock = true;
+      ProtectControlGroups = true;
+      ProtectHome = true;
+      ProtectHostname = true;
+      ProtectKernelLogs = true;
+      ProtectKernelModules = true;
+      ProtectKernelTunables = true;
+      ProtectProc = "invisible";
+      ProtectSystem = "strict";
+      RestrictAddressFamilies = "AF_INET AF_INET6";
+      RestrictNamespaces = true;
+      RestrictRealtime = true;
+      RestrictSUIDSGID = true;
+      SystemCallArchitectures = "native";
+      SystemCallFilter = [
+        "@system-service"
+        "~ @resources @privileged"
+      ];
+      UMask = "077";
+    };
+  };
+
+  system.stateVersion = "23.11";
+}
@@ -0,0 +1,22 @@
+#!/usr/bin/env -S jq -Mrf
+
+def round3:
+    . * 1000 | round | . / 1000
+    ;
+
+def stats($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")
@@ -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)
@@ -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
@@ -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;
+};
+
+};
@@ -1,11 +1,7 @@
-#include "CharPtrCast.hh"
-#include "DisallowedDecls.hh"
-#include "ForeignExceptions.hh"
-#include "HasPrefixSuffix.hh"
-#include "NeverAsync.hh"
-#include "UnsafeCCalls.hh"
 #include <clang-tidy/ClangTidyModule.h>
 #include <clang-tidy/ClangTidyModuleRegistry.h>
+#include "FixIncludes.hh"
+#include "HasPrefixSuffix.hh"

 namespace nix::clang_tidy {
 using namespace clang;
@@ -15,11 +11,7 @@ class NixClangTidyChecks : public ClangTidyModule {
    public:
        void addCheckFactories(ClangTidyCheckFactories &CheckFactories) override {
            CheckFactories.registerCheck<HasPrefixSuffixCheck>("lix-hasprefixsuffix");
-            CheckFactories.registerCheck<CharPtrCastCheck>("lix-charptrcast");
-            CheckFactories.registerCheck<NeverAsync>("lix-never-async");
-            CheckFactories.registerCheck<DisallowedDeclsCheck>("lix-disallowed-decls");
-            CheckFactories.registerCheck<ForeignExceptions>("lix-foreign-exceptions");
-            CheckFactories.registerCheck<UnsafeCCalls>("lix-unsafe-c-calls");
+            CheckFactories.registerCheck<FixIncludesCheck>("lix-fixincludes");
        }
 };

@@ -10,13 +10,13 @@ goal and is there as an example), `HasPrefixSuffixCheck`.
 One file:

 ```
-ninja -C build && clang-tidy --checks='-*,lix-*' --load=build/liblix-clang-tidy.so -p ../../build -header-filter '\.\./lix/.*\.h' --fix ../../lix/libcmd/installables.cc
+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 ../../build -header-filter '\.\./lix/.*\.h' -fix ../../lix | tee -a clang-tidy-result
+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
@@ -40,7 +40,7 @@ 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 lix/libcmd/installables.cc`.
+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++.
@@ -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)
@@ -1 +0,0 @@
-*
@@ -1 +0,0 @@
-*
@@ -20,7 +20,7 @@ OUTPUT_DIRECTORY       = @docdir@
 # 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          = "Lix: A modern, delicious implementation of the Nix package manager; unstable internal interfaces"
+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.
@@ -33,7 +33,32 @@ GENERATE_LATEX         = NO
 # spaces. See also FILE_PATTERNS and EXTENSION_MAPPING
 # Note: If this tag is empty the current directory is searched.

-INPUT                  = @INPUT_PATHS@
+# 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
@@ -72,15 +97,3 @@ EXPAND_AS_DEFINED      = \
  DECLARE_WORKER_SERIALISER \
  DECLARE_SERVE_SERIALISER \
  LENGTH_PREFIXED_PROTO_HELPER
-
-# The STRIP_FROM_PATH tag can be used to strip a user-defined part of the path.
-# Stripping is only done if one of the specified strings matches the left-hand
-# part of the path. The tag can be used to show relative paths in the file list.
-# If left blank the directory from which doxygen is run is used as the path to
-# strip.
-#
-# Note that you can specify absolute paths here, but also relative paths, which
-# will be relative from the directory where doxygen is started.
-# This tag requires that the tag FULL_PATH_NAMES is set to YES.
-
-STRIP_FROM_PATH        = "@PROJECT_SOURCE_ROOT@"
@@ -1,35 +1,3 @@
-internal_api_sources = [
-  'lix/libcmd',
-  'lix/libexpr',
-  'lix/libexpr/flake',
-  'tests/unit/libexpr',
-  'tests/unit/libexpr/value',
-  'tests/unit/libexpr/test',
-  'tests/unit/libexpr/test/value',
-  'lix/libexpr/value',
-  'lix/libfetchers',
-  'lix/libmain',
-  'lix/libstore',
-  'lix/libstore/build',
-  'lix/libstore/builtins',
-  'tests/unit/libstore',
-  'tests/unit/libstore/test',
-  'lix/libutil',
-  'tests/unit/libutil',
-  'tests/unit/libutil/test',
-  'lix/nix',
-  'lix/nix-env',
-  'lix/nix-store',
-]
-
-# We feed Doxygen absolute paths so it can be invoked from any working directory.
-internal_api_sources_absolute = []
-foreach src : internal_api_sources
-  internal_api_sources_absolute += '"' + (meson.project_source_root() / src) + '"'
-endforeach
-
-internal_api_sources_oneline = ' \\\n  '.join(internal_api_sources_absolute)
-
 doxygen_cfg = configure_file(
  input : 'doxygen.cfg.in',
  output : 'doxygen.cfg',
@@ -37,16 +5,22 @@ doxygen_cfg = configure_file(
    'PACKAGE_VERSION': meson.project_version(),
    'RAPIDCHECK_HEADERS': rapidcheck_meson.get_variable('includedir'),
    'docdir' : meson.current_build_dir(),
-    'INPUT_PATHS' : internal_api_sources_oneline,
-    'PROJECT_SOURCE_ROOT' : meson.project_source_root(),
  },
 )

 internal_api_docs = custom_target(
  'internal-api-docs',
  command : [
-    doxygen.full_path(),
-    '@INPUT0@',
+    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,
@@ -24,8 +24,8 @@ def map_contents_recursively(transformer):
 def process_command:
    .[0] as $context |
    .[1] as $body |
-	# XXX FUTURE: drop sections once mdBook is at 0.5.0 or above in nixpkgs
-	$body | (.items? // .sections) |= map(map_contents_recursively(if $context.renderer == "html" then transform_anchors_html else transform_anchors_strip end))
-	;
+    $body + {
+        sections: $body.sections | map(map_contents_recursively(if $context.renderer == "html" then transform_anchors_html else transform_anchors_strip end)),
+    };

 process_command
@@ -7,8 +7,9 @@ create-missing = false
 [output.html]
 additional-css = ["custom.css"]
 additional-js = ["redirects.js"]
-# Jumps directly into a new Gerrit CL editing the file in question.
-edit-url-template = "https://gerrit.lix.systems/admin/repos/edit/repo/lix/branch/main/file/doc/manual/{path}"
+# 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.
@@ -22,21 +23,20 @@ fold.level = 30
 # 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 substitute.py"
+command = "python3 doc/manual/substitute.py"
 before = ["anchors", "links"]

 [preprocessor.anchors]
 renderers = ["html"]
-command = "jq --from-file anchors.jq"
+command = "jq --from-file doc/manual/anchors.jq"

 [output.markdown]

-# XXX FUTURE: may be reenabled once mdBook 0.5.0 or above and matching mdbook-linkchecker are in nixpkgs
-#[output.linkcheck]
+[output.linkcheck]
 # no Internet during the build (in the sandbox)
-#follow-web-links = false
+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"
+warning-policy = "ignore"
@@ -3,19 +3,11 @@
 #
 # 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

-9p4:
-  display_name: Ersei Saggi
-  github: 9p4
-
 Artturin:
  github: Artturin

@@ -40,70 +32,22 @@ alois31:
  forgejo: alois31
  github: alois31

-andrewhamon:
-  display_name: Andrew Hamon
-  github: andrewhamon
-
 artemist:
  display_name: Artemis Tosini
  forgejo: artemist

-bb010g:
-  display_name: Dusk Banks
-  forgejo: bb010g
-  github: bb010g
-
-blitz:
-  display_name: Julian Stecklina
-  github: blitz
-
 cole-h:
  display_name: Cole Helbling
  github: cole-h

-commentator2.0:
-  display_name: Commentator2.0 (Rutile)
-  forgejo: commentatorforall
-  github: CommentatorForAll
-
-delan:
-  display_name: delan
-  forgejo: delan
-  github: delan
-
-delroth:
-  github: delroth
-
-detroyejr:
-  display_name: Jonathan De Troye
-  github: detroyejr
-
 edolstra:
  display_name: Eelco Dolstra
  github: edolstra

-emilazy:
-  display_name: Emily
-  forgejo: emilazy
-  github: emilazy
-
 ericson:
  display_name: John Ericson
  github: ericson2314

-getchoo:
-  display_name: Seth Flynn
-  forgejo: getchoo
-  github: getchoo
-
-gilice:
-  forgejo: gilice
-
-goldstein:
-  display_name: goldstein
-  forgejo: goldstein
-  github: GoldsteinE
-
 horrors:
  display_name: eldritch horrors
  forgejo: pennae
@@ -112,62 +56,10 @@ horrors:
 iFreilicht:
  github: iFreilicht

-ian-h-chamberlain:
-  forgejo: ian-h-chamberlain
-  github: ian-h-chamberlain
-
-infinisil:
-  github: infinisil
-
-isabelroses:
-  forgejo: isabelroses
-  github: isabelroses
-
 jade:
  forgejo: jade
  github: lf-

-just1602:
-  forgejo: just1602
-
-k900:
-  display_name: K900
-  forgejo: K900
-  github: K900
-
-kasimeka:
-  display_name: ورد
-  forgejo: janw4ld
-  github: kasimeka
-
-kfears:
-  display_name: KFears
-  forgejo: kfearsoff
-  github: kfearsoff
-
-kiara:
-  github: KiaraGrouwstra
-
-kjeremy:
-  github: kjeremy
-
-kloenk:
-  display_name: Fiona Behrens
-  forgejo: kloenk
-  github: kloenk
-
-lheckemann:
-  forgejo: lheckemann
-  github: lheckemann
-
-lily:
-  forgejo: lilyinstarlight
-  github: lilyinstarlight
-
-lilyball:
-  forgejo: lilyball
-  github: lilyball
-
 lovesegfault:
  github: lovesegfault

@@ -178,60 +70,19 @@ ma27:
 matthewbauer:
  github: matthewbauer

-mic92:
-  github: mic92
-
 midnightveil:
  display_name: julia
  forgejo: midnightveil
  github: midnightveil

-milibopp:
-  display_name: Emilia Bopp
-  forgejo: milibopp
-  github: milibopp
-
-nan-git:
-  display_name: NaN-git
-  github: NaN-git
-
 ncfavier:
  github: ncfavier

-not-my-profile:
-  display_name: Martin Fischer
-  github: not-my-profile
-
-p-e-meunier:
-  display_name: Pierre-Etienne Meunier
-  github: P-E-Meunier
-
-pamplemousse:
-  display_name: Xavier Maso
-  github: pamplemousse
-
-piegames:
-  display_name: piegames
-  forgejo: piegames
-  github: piegamesde
-
-poliorcetics:
-  display_name: Poliorcetics
-  github: poliorcetics
-
 puck:
  display_name: puck
  forgejo: puck
  github: puckipedia

-quantenzitrone:
-  display_name: Zitrone
-  forgejo: quantenzitrone
-
-quantumjump:
-  display_name: Quantum Jump
-  github: QuantumBJump
-
 r-vdp:
  github: r-vdp

@@ -244,18 +95,6 @@ roberth:
  display_name: Robert Hensing
  github: roberth

-seppel3210:
-  github: Seppel3210
-
-teofilc:
-  forgejo: teofilc
-  github: TeofilC
-
-thubrecht:
-  display_name: Tom Hubrecht
-  forgejo: tom-hubrecht
-  github: Tom-Hubrecht
-
 thufschmitt:
  display_name: Théophane Hufschmitt
  github: thufschmitt
@@ -268,31 +107,9 @@ valentin:
  display_name: Valentin Gagarin
  github: fricklerhandwerk

-vigress8:
-  display_name: Vigress
-  forgejo: vigress8
-  github: vigress8
-
-vlinkz:
-  display_name: Victor Fuentes
-  forgejo: vlinkz
-  github: vlinkz
-
 winter:
  forgejo: winter
  github: winterqt

-xanderio:
-  github: xanderio
-
-xokdvium:
-  github: xokdvium
-
-yorickvp:
-  github: yorickvp
-
 yshui:
  github: yshui
-
-zimbatm:
-  github: zimbatm
@@ -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}
+
+      ${impureNotice}
+
+      </dd>
+    '';
+in
+concatStringsSep "\n" (attrValues (mapAttrs showBuiltin builtinsInfo))
@@ -0,0 +1,35 @@
+let
+  inherit (builtins) concatStringsSep attrValues mapAttrs;
+  inherit (import ./utils.nix) optionalString squash;
+in
+
+builtinsInfo:
+let
+  showBuiltin =
+    name:
+    {
+      doc,
+      args,
+      arity,
+      experimental-feature,
+    }:
+    let
+      experimentalNotice = optionalString (experimental-feature != null) ''
+        This function is only available if the [${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))
@@ -1,134 +1,26 @@
-with builtins;
-
 let
-  splitLines = s: filter (x: !isList x) (split "\n" s);
-
-  concatStrings = concatStringsSep "";
-
-  replaceStringsRec =
-    from: to: string:
-    # recursively replace occurrences of `from` with `to` within `string`
-    # example:
-    #     replaceStringRec "--" "-" "hello-----world"
-    #     => "hello-world"
-    let
-      replaced = replaceStrings [ from ] [ to ] string;
-    in
-    if replaced == string then string else replaceStringsRec from to replaced;
-
-  squash = replaceStringsRec "\n\n\n" "\n\n";
-
-  trim =
-    string:
-    # trim trailing spaces and squash non-leading spaces
-    let
-      trimLine =
-        line:
-        let
-          # separate leading spaces from the rest
-          parts = split "(^ *)" line;
-          spaces = head (elemAt parts 1);
-          rest = elemAt parts 2;
-          # drop trailing spaces
-          body = head (split " *$" rest);
-        in
-        spaces + replaceStringsRec "  " " " body;
-    in
-    concatStringsSep "\n" (map trimLine (splitLines string));
-
-  # FIXME: O(n^2)
-  unique = foldl' (acc: e: if elem e acc then acc else acc ++ [ e ]) [ ];
-
-  nameValuePair = name: value: { inherit name value; };
-
-  filterAttrs =
-    pred: set:
-    listToAttrs (
-      concatMap (
-        name:
-        let
-          v = set.${name};
-        in
-        if pred name v then [ (nameValuePair name v) ] else [ ]
-      ) (attrNames set)
-    );
-
-  optionalString = cond: string: if cond then string else "";
-
-  showSetting =
-    { inlineHTML }:
-    name:
-    {
-      description,
-      documentDefault,
-      defaultValue,
-      aliases,
-      value,
-      experimentalFeature,
-    }:
-    let
-      result = squash ''
-        - ${
-          if inlineHTML then ''<span id="conf-${name}">[`${name}`](#conf-${name})</span>'' else ''`${name}`''
-        }
-
-        ${indent "  " body}
-      '';
-
-      experimentalFeatureNote = optionalString (experimentalFeature != null) ''
-        > **Warning**
-        > This setting is part of an
-        > [experimental feature](@docroot@/contributing/experimental-features.md).
-
-        To change this setting, you need to make sure the corresponding experimental feature,
-        [`${experimentalFeature}`](@docroot@/contributing/experimental-features.md#xp-feature-${experimentalFeature}),
-        is enabled.
-        For example, include the following in [`nix.conf`](#):
-
-        ```
-        extra-experimental-features = ${experimentalFeature}
-        ${name} = ...
-        ```
-      '';
-
-      # separate body to cleanly handle indentation
-      body = ''
-        ${description}
-
-        ${experimentalFeatureNote}
-
-        **Default:** ${showDefault documentDefault defaultValue}
-
-        ${showAliases aliases}
-      '';
-
-      showDefault =
-        documentDefault: defaultValue:
-        if documentDefault then
-          # a StringMap value type is specified as a string, but
-          # this shows the value type. The empty stringmap is `null` in
-          # JSON, but that converts to `{ }` here.
-          if defaultValue == "" || defaultValue == [ ] || isAttrs defaultValue then
-            "*empty*"
-          else if isBool defaultValue then
-            if defaultValue then "`true`" else "`false`"
-          else
-            "`${toString defaultValue}`"
-        else
-          "*machine-specific*";
-
-      showAliases =
-        aliases:
-        optionalString (aliases != [ ])
-          "**Deprecated alias:** ${(concatStringsSep ", " (map (s: "`${s}`") aliases))}";
-    in
-    result;
-
-  indent =
-    prefix: s: concatStringsSep "\n" (map (x: if x == "" then x else "${prefix}${x}") (splitLines s));
-
-  showSettings =
-    args: settingsInfo: concatStrings (attrValues (mapAttrs (showSetting args) settingsInfo));
+  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:
@@ -225,7 +117,7 @@ let
          showCategory = cat: ''
            ${optionalString (cat != "") "**${cat}:**"}

-            ${listOptions (filterAttrs (n: v: v.category == cat && !v.hidden) allOptions)}
+            ${listOptions (filterAttrs (n: v: v.category == cat) allOptions)}
          '';
          listOptions = opts: concatStringsSep "\n" (attrValues (mapAttrs showOption opts));
          showOption =
@@ -0,0 +1,9 @@
+with builtins;
+with import ./utils.nix;
+
+let
+  showExperimentalFeature = name: doc: ''
+    - [`${name}`](@docroot@/contributing/experimental-features.md#xp-feature-${name})
+  '';
+in
+xps: indent "  " (concatStrings (attrValues (mapAttrs showExperimentalFeature xps)))
@@ -0,0 +1,13 @@
+with builtins;
+with import ./utils.nix;
+
+let
+  showExperimentalFeature =
+    name: doc:
+    squash ''
+      ## [`${name}`]{#xp-feature-${name}}
+
+      ${doc}
+    '';
+in
+xps: (concatStringsSep "\n" (attrValues (mapAttrs showExperimentalFeature xps)))
@@ -1,7 +1,6 @@
 nix_env_for_docs = {
  'HOME': '/dummy',
  'NIX_CONF_DIR': '/dummy',
-  'XDG_CONFIG_HOME': '/dummy',
  'NIX_SSL_CERT_FILE': '/dummy/no-ca-bundle.crt',
  'NIX_STATE_DIR': '/dummy',
  'NIX_CONFIG': 'cores = 0',
@@ -16,21 +15,67 @@ nix_eval_for_docs_common = nix_for_docs + [
 ]
 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,
-  # FIXME: put the actual lib targets in here? meson have introspection challenge 2024 though.
-  build_always_stale : true,
 )

 generate_manual_deps = files(
  'generate-deps.py',
 )

-# Generates new-cli pages  and conf-file.md.
+# 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')

@@ -42,9 +87,8 @@ manual = custom_target(
    '-c',
    '''
        @0@ @INPUT0@ @CURRENT_SOURCE_DIR@ > @DEPFILE@
-        cd @3@
-        @1@ build . -d @2@ | { grep -Fv "because fragment resolution isn't implemented" || :; }
        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
@@ -52,7 +96,6 @@ manual = custom_target(
      python.full_path(),
      mdbook.full_path(),
      meson.current_build_dir(),
-      meson.current_source_dir()
    ),
  ],
  input : [
@@ -63,31 +106,29 @@ manual = custom_target(
    nix3_cli_files,
    experimental_features_shortlist_md,
    experimental_feature_descriptions_md,
-    deprecated_features_shortlist_md,
-    deprecated_feature_descriptions_md,
    conf_file_md,
    builtins_md,
    builtin_constants_md,
    rl_next_generated,
-    nix,
  ],
  output : [
    'manual',
    'markdown',
  ],
-  install : true,
-  install_dir : [
-    datadir / 'doc/nix',
-    false,
-  ],
  depfile : 'manual.d',
  env : {
    'RUST_LOG': 'info',
-    'MANUAL_SUBSTITUTE_SEARCH': meson.current_build_dir() / 'src',
+    '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',
    [
@@ -145,7 +186,6 @@ foreach command : nix_nested_manpages
      ],
      input : [
        manual_md,
-        nix,
      ],
      output : command[0] + '-' + page + '.1',
      install : true,
@@ -258,7 +298,6 @@ foreach page : nix3_manpages
    input : [
      'render-manpage.sh',
      manual_md,
-      nix,
    ],
    output : page + '.1',
    install : true,
@@ -302,7 +341,6 @@ foreach entry : nix_manpages
      'render-manpage.sh',
      manual_md,
      entry.get(3, []),
-      nix,
    ],
    output : '@0@.@1@'.format(entry[0], entry[1]),
    install : true,
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!/bin/sh

 set -euo pipefail

@@ -345,7 +345,7 @@ const redirects = {
    "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",
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!/bin/sh

 set -euo pipefail

@@ -1,15 +0,0 @@
---
-synopsis: "Add `builtins.warn` for emitting warnings from Nix code"
-cls: [2248]
-category: "Features"
-credits: [milibopp, Qyriad]
---
-
-Lix now has a builtin function for emitting warnings.
-Like `builtins.trace`, it takes two arguments: the message to emit, and the expression to return.
-_Unlike_ `builtins.trace`, `builtins.warn` requires the first argument — the message — to be a string.
-In the future we may extend `builtins.warn` to accept a more structured API.
-
-To go along with this, we also have two new config settings:
- [`debugger-on-warn`](@docroot@/command-ref/conf-file.md#conf-debugger-on-warn), which, when used with `--debugger`, makes `builtins.warn` also function like [`builtins.break`](@docroot@/language/builtins.md#builtins-break).
- [`abort-on-warn`](@docroot@/command-ref/conf-file.md#conf-abort-on-warn), which aborts evaluation entirely after the warning is emitted.
@@ -1,13 +0,0 @@
---
-synopsis: "Deprecate shadowing internal files through the Nix search path"
-issues: [998]
-cls: [4632]
-category: "Breaking Changes"
-credits: [thubrecht]
---
-
-As Lix uses the path `<nix/fetchurl.nix>` for bootstrapping purposes, the ability to shadow it by adding `nix=/some/path` (or `/other/path` that contains a `nix` directory) to the search path is not desirable.
-
-To alleviate potential issues, Lix now emits a warning when the Nix search path contains potential shadows for internal files, which will be changed to an error in a future release.
-
-The warning can be disabled by enabling the deprecated feature `nix-path-shadow`.
@@ -1,10 +0,0 @@
---
-synopsis: "Warn instead of erroring when the final destination of a transfer changes in-flight"
-cls: [4641]
-issues: [fj#1004]
-category: "Miscellany"
-credits: [thubrecht]
---
-
-Lix will now emit a warning during downloads where the final destination changes suddently mid-transfer instead of throwing an error.
-This transfer behavior has been known to happen very rarely while fetching from some CDNs.
@@ -1,10 +0,0 @@
---
-synopsis: 'functional lang migration'
-issues: [lix#856]
-cls: [3213, 3214, 3215, 3224, 4092, 4093, 4094, 4095, 4096, 4097, 4098, 4099, 4100, 4101, 4102, 4103, 4104, 4105, 4106, 4107, 4108, 4109, 4110, 4111, 4112, 4113, 4114, 4115, 4116, 4117, 4122, 4123, 4269, 4270, 4271, 4272, 4273, 4274, 4347, 4348, 4349, 4350, 4351, 4352, 4569, 4570, 4571, 4572, 4573, 4574, 4596, 4597, 4598, 4599, 4600, 4601, 4602, 4603, 4604, 4605]
-category: Development
-credits: [piegames, commentator2.0]
---
-We have done it! The functional/lang framework has now been fully migrated to functional2/lang.
-This means: no more `just clean` and `just install` mess and whatever because one removed a test.
-The lang test suite is also getting a face lift, with an improved folder structure and restructuring of many tests.
@@ -1,10 +0,0 @@
---
-synopsis: "Allow remote builders to be configured using TOML"
-cls: [4533]
-category: "Features"
-credits: [commentator2.0, Qyriad]
---
-Lix now supports configuring remote builders using a TOML file instead of the old, very cursed and incomprehensible format.
-This comes with not only a human-understandable file, but also with better messages and error reports on misconfiguration.
-
-A more detailed Documentation can be found on the [distributed-builds](@docroot@/advanced-topics/distributed-builds.md) Wiki-page
@@ -1,8 +0,0 @@
---
-synopsis: "Default to showing build logs in the new-style (nix3) CLI"
-cls: [4674]
-category: "Miscellany"
-credits: [k900]
---
-
-Lix will now show logs by default, in addition to the progress bar, when invoked through the new-style "nix3" CLI (`nix build`, etc)
@@ -1,31 +0,0 @@
---
-synopsis: "Move /root/.cache/nix to /var/cache/nix by default"
-cls: [4671]
-issues: [fj#634]
-category: "Breaking Changes"
-credits: [raito]
---
-
-By default, Lix attempts to locate a cache directory for its operations (such
-as the narinfo cache) by checking the value of `$XDG_CACHE_DIR`.
-
-However, since the Nix daemon is a system service, using `$XDG_CACHE_DIR` is
-not typical in this context.
-
-To address this, systemd provides a better solution. Specifically, when
-`CacheDirectory=` is set in the `[Service]` section of a systemd unit, it
-automatically sets the `$CACHE_DIRECTORY` environment variable and systemd will
-manage that cache directory for us.
-
-Now, our systemd unit includes `CacheDirectory=nix`, which sets the
-`$CACHE_DIRECTORY` and takes precedence over `$XDG_CACHE_DIR`.
-
-If the daemon is run under user units, systemd will automatically set
-`$XDG_CACHE_DIR`.
-
-If neither of these variables is set, Lix falls back to its default behavior.
-By default, Lix will try to find a cache directory for its various operations
-(e.g. narinfo cache) by looking into `$XDG_CACHE_DIR`.
-
-In summary, what was stored in `/root/.cache/nix` is now moved to
-`/var/cache/nix/nix`.
@@ -1,9 +0,0 @@
---
-synopsis: "Add an indication of nix-shell nesting depth"
-cls: [4657]
-issues: [fj#826]
-category: "Improvements"
-credits: [thubrecht]
---
-
-When in a nix shell (either via a `nix-shell` or a `nix develop` invocation), a variable `NIX_SHELL_LEVEL` is exported to indicate the nesting depth of nix shells.
@@ -1,20 +0,0 @@
---
-synopsis: Derivations can now be printed in detail in `nix repl`
-cls: [3842]
-category: Improvements
-credits: [Lunaphied]
---
-
-Traditionally derivations printed in the REPL would only print a formatted object
-representing the path of the derivation file it refers to. This makes inspecting
-the enhanced derivation attribute sets encountered from `mkDerivation` or similar
-wrappers more difficult. Even the `:p`/`:print` command would not elaborate attribute sets
-tagged as a derivation.
-
-With this change you can now use `:p`/`:print` to directly inspect a derivation
-by providing one as the top-level object. Derivation attribute sets will only be
-printed two levels deep and internal derivation attrsets will remain in unexpanded
-path form as before. `drvAttrs` will also be elided as these attributes are already
-present in the top-level attribute set of the derivation. These heuristics provide
-a balance between readability and functionality. When the `:p`/`:print` is omitted,
-a bare derivation is printed in the path format as before.
@@ -1,37 +0,0 @@
---
-synopsis: Remove `fetch-closure` experimental feature
-issues: [fj#1010]
-cls: [4595]
-category: "Breaking Changes"
-credits: [just1602]
---
-
-The `fetch-closure` experimental feature has been removed.
-
-Outside of allowing the user to import closure from binary cache,
-`fetchClosure` also allow you to do the following:
-
-* rewrite non-CA path to CA
-* reject non-CA paths at fetching time
-* reject CA paths at fetching time
-
-Some people are using those mechanism to prevent users from having to build any
-package and force going via the declared cache or as a way to use ancient/old
-software without paying the evaluation cost of a second nixpkgs.
-
-Both use cases are somewhat of an antipattern in Nix semantics. If the user
-cannot fetch a program directly via the substituter mechanism and fall back to
-local build, this is a feature AND a misconfiguration. If the user cannot build
-certain derivations because they are too expensive, the build directives should
-pass `-j0` or similar.
-
-As for the second usecase, there's a different way to do it that also allows to
-have a way to reproduce the paths that are hardcoded in that file, perform
-`import (fetchurl "https://my-cache/${hashparts storepath}.drv")` rather, i.e.
-an IFD to a possibly well known name. The backend can generate them on the fly
-or once, and possess stable names.
-
-Finally, as for the non-CA → CA features, Lix removed ca-derivations.
-fetchClosure offers ca-derivations-like features which suffers from similar
-shortcomings albeit lessened. It only follows that we should rather deprecate
-and remove these capabilities.
@@ -1,15 +0,0 @@
---
-synopsis: "Lix daemons are now fully socket-activated on systemd setups"
-cls: []
-issues: [1030]
-category: "Miscellany"
-credits: [horrors]
---
-
-When launched by systemd, Lix no longer uses a persistent daemon process and uses systemd socket
-activation instead. This is necessary to support the `cgroups` and `auto-allocate-uids` features
-and may improve observability of daemon behavior with common systemd-based monitoring solutions.
-
-The old behavior with a single persistent daemon is still available, but disabled by default. It
-is not possible to enable both a persistent daemon and socket activation, starting one stops the
-other automatically. Existing installations should not require any changes when they're updated.
@@ -20,6 +20,7 @@
  - [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)
@@ -39,9 +40,6 @@
  - [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)
-  - [Pasta](advanced-topics/pasta.md)
- [Known Issues](known-issues/known-issues.md)
-  - [Limitations around non-isolated builds](known-issues/non-isolated-build-limits.md)
 - [Command Reference](command-ref/command-ref.md)
  - [Common Options](command-ref/opt-common.md)
  - [Common Environment Variables](command-ref/env-common.md)
@@ -194,16 +192,11 @@
  - [Hacking](contributing/hacking.md)
  - [Testing](contributing/testing.md)
  - [Experimental Features](contributing/experimental-features.md)
-  - [Deprecated Features](contributing/deprecated-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 2.94 (2025-11-17)](release-notes/rl-2.94.md)
-  - [Lix 2.93 (2025-05-09)](release-notes/rl-2.93.md)
-  - [Lix 2.92 (2025-01-18)](release-notes/rl-2.92.md)
-  - [Lix 2.91 (2024-08-12)](release-notes/rl-2.91.md)
+  <!-- RELENG-AUTO-INSERTION-MARKER (see releng/release_notes.py) -->
  - [Lix 2.90 (2024-07-10)](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)
@@ -41,17 +41,104 @@ contains Nix.
 > 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 HOST | sudo tee -a ~root/.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.

-
-## Configuration
-
 The list of remote machines can be specified on the command line or in
-the Lix configuration file. The former is convenient for testing.
-Additionally, there are two supported formats to configure remote builders:
-The legacy, "space"-separated format and starting with Lix 2.95.0, a TOML.
+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.

@@ -70,180 +157,3 @@ 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`.
-
---
-
-Each machine specification consists of the following attributes.
-How those are combined within the configuration file differs for the formats, and will be explained further down.
-
-1.  `uri` (**required**)
-    The URI of the remote store in the format
-    `ssh[-ng]://[username@]hostname[?port=<port>]`, e.g. `ssh://nix@mac` or `ssh://mac`.
-    If the ssh server is not listening on port 22 (e.g. port 1337 in this case)
-    the URI would be `ssh[-ng]://nix@mac?port=1337`. The hostname
-    may be an alias defined in your `~/.ssh/config`.
-
-2.  `system-types` (**optional**)
-    A 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` and `x86_64-linux`.
-
-    Defaults to the local platform type
-
-3.  `ssh-key` (**optional**)
-    The SSH identity file to be used to log in to the remote machine.
-
-    Defaults to SSHs regular identities.
-
-4.  `jobs` (**optional**)
-    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 divided by the cores within the target machines configuration, i.e. `jobs * cores ~= cpu cores`
-
-    Defaults to 1; must be a positive integer.
-
-5.  `speed-factor`
-    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.
-
-    Defaults to 1; must be a positive float.
-
-6.  `supported-features` (**optional**)
-    A list of *supported features*. If a derivation has
-    the `requiredSystemFeatures` attribute, then Lix will only schedule
-    the derivation on a machine that has the specified features. For
-    example, the attribute
-
-    ```nix
-    requiredSystemFeatures = [ "kvm" ];
-    ```
-
-    will cause the build to be performed on a machine that has the `kvm`
-    feature.
-
-    Defaults to an empty list.
-
-7.  `mandatory-features` (**optional**)
-    A list of *mandatory features*. A machine will only
-    be used to build a derivation if all the machine’s mandatory
-    features appear in the derivation’s `requiredSystemFeatures`
-    attribute.
-
-    Defaults to an empty list.
-
-8.  `ssh-public-host-key` (**optional**)
-    The public host key of the remote machine.
-
-    Defaults to basic ssh behavior (checking contests of the known-hosts file)
-
-
-### Using a TOML configuration
-
-Each machine is configured as an attribute within the map called `machines`.
-The attributes name is the machines name.
-Attributes can be in any order.
-
-For example:
-
-```toml
-version = 1
-
-[machines.andesite]
-uri = "ssh://lix@andesite.lix.systems" # toml also allows for comments
-system-types = ["i686-linux"]
-jobs = 8
-speed-factor = 1.0
-supported-features = ["kvm"]
-ssh-key = "/home/deepslate/.ssh/id_ed25519"
-
-[machines.diorite]
-uri = "ssh://lix@diorite.lix.systems"
-system-types = ["i686-linux"]
-jobs = 8
-speed-factor = 2.0
-ssh-key = "/home/deepslate/.ssh/id_ed25519"
-
-[machines.granite]
-uri = "ssh://lix@granite.lix.systems"
-system-types = ["i686-linux"]
-jobs = 1
-speed-factor = 2.0
-supported-features = ["kvm", "benchmark"]
-ssh-key = "/home/deepslate/.ssh/id_ed25519"
-
-[machines.legacy]
-uri = "ssh://nix@nix-15-11.nixos.org"
-enable = false
-
-```
-
-> **Note**
->
-> If the version tag is omitted (e.g. in the CLI), it defaults to the latest version.
-> It is strongly recommended to always provide a version tag for configuration within files to avoid breakage.
-
-For testing purposes, one can also define a builder ad hoc on the CLI as follows:
-`--builders 'machines.andesite = {uri = "ssh://lix@andesite.lix.systems", jobs = 8}'`
-
-
-#### Special handling of fields
- - `enable` (**optional**)
-    If set to false, the declared machine will not be loaded.
-    This allows one to statically disable machines.
-
-    Defaults to true
-
-### Using the legacy format
-> **Warning**
->
-> This format is frozen and new features / configuration options will not be backported to this format.
-
-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'
-```
-
-Every machine specification consists of the elements listed in the section above, seperated by any amount of spaces or tabs.
-The Attributes need to be provided **in order** and without names.
-To leave a field at its default, set it to `-`.
-Lists are colon seperated, without additional spaces.
-
-```
-lix@andesite.lix.systems    i686-linux      /home/deepslate/.ssh/id_ed25519        8 1 kvm
-lix@diorite.lix.systems     i686-linux      /home/deepslate/.ssh/id_ed25519        8 2
-lix@granite.lix.systems     i686-linux      /home/deepslate/.ssh/id_ed25519        1 2 kvm benchmark
-```
-
-#### Special handling of fields
- `uri`: Due to backward compatibility, the `ssh://` may be omitted for the store-uri.
- `ssh-public-host-key`: The key must be provided encoded in base64. Specifically calculated via `base64 -w0 /etc/ssh/ssh_host_ed25519_key.pub`
-
-
-### Format detection
-
-At first, the given configuration is being parsed syntactically as a toml.
-If parsing fails and the given configuration contains a `"` the error is presented to the user, as those characters are necessary for TOML, but disallowed for the legacy format.
-Otherwise, parsing is retried using the legacy format.
-If non-syntactic errors are detected within the toml, the exception will always be shown to the user directly.
-
-
-## Builder selection
-The configuration(s) above specify several machines that can perform `i686-linux` builds.
-However, `granite` will only do builds that have the attribute
-
-```nix
-requiredSystemFeatures = [ "benchmark" ];
-```
-
-or
-
-```nix
-requiredSystemFeatures = [ "benchmark" "kvm" ];
-```
-
-`diorite` cannot do builds that require `kvm`, but `andesite` does support
-such builds. For regular builds, `diorite` will be preferred over
-`andesite` because it has a higher speed factor.
@@ -1,19 +0,0 @@
-# [Pasta](https://passt.top/passt/about/): a network sandbox for fixed-output derivations
-
-## Introduction
-
-This section only applies to **Linux systems** as Pasta is a Linux-only measure.
-
-Since [CVE-2025-46416](https://lix.systems/blog/2025-06-24-lix-cves/), the Lix project decided to adopt [Pasta](https://passt.top/passt/about/) for all fixed-output derivations, protecting against various attack vectors such as UNIX abstract domain sockets or more manipulation at the network layer from a malicious fixed-output derivation code.
-
-Pasta acts as a translation layer between a layer-2 network interface and layer-4 sockets (TCP, UDP, ICMP/ICMPv6 echo) on the host. It requires no special privileges and can serve as a alternative to [SLiRP](https://en.wikipedia.org/wiki/Slirp) which was used [by Guix to mitigate the same problem](https://codeberg.org/guix/guix/commit/fb42611b8f27960304db5a1c0d33b8371dcde2a8).
-
-## How to disable Pasta?
-
-It's sufficient to pass `pasta-path = ""` in your `/etc/nix/nix.conf` or on the command line `--pasta-path ""` of a Lix invocation.
-
-## Known issues surrounding Pasta
-
- Only the first DNS server in `/etc/resolv.conf` is considered: failover is not possible.
- [Reduced feature set compared to the Linux kernel](https://passt.top/passt/about/#features)
- [Performance overhead in multi-gigabits contexts and IMIX MTUs](https://passt.top/passt/about/#performance_1)
@@ -22,9 +22,9 @@ The following [concept map] shows its main components (rectangles), the objects
           |                   |
 +----------|-------------------|--------------------------------+
 | Nix impl.|                   V                                |
-| (Lix)    |       +------------------------+                   |
-|          |       | command line interface |------.            |
-|          |       +------------------------+      |            |
+| (Lix)    |      +-------------------------+                   |
+|          |      | commmand line interface |------.            |
+|          |      +-------------------------+      |            |
 |          |                   |                   |            |
 |    evaluated by            calls              manages         |
 |          |                   |                   |            |
@@ -34,15 +34,9 @@ keep-outputs = true       # Nice for developers
 keep-derivations = true   # Idem
 ```

-Other files can be included with a line like `include <path>`.
+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.

-Paths in `include`s and option values are interpreted relative to the current configuration file.
-In user configuration files, paths starting with `~/` are tilde expanded (by replacing the tilde by the value of `$HOME`).
-
-Only user configuration files (like `$XDG_CONFIG_HOME/nix/nix.conf` or the files listed in `$NIX_USER_CONF_FILES`) can use tilde paths relative to your home directory.
-Configuration listed in the `$NIX_CONFIG` environment variable may not use relative paths.
-
 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.

@@ -1,12 +0,0 @@
-<!--
-  File-ish argument syntax summary.
-  This file gets included into pages like nix-build.md and nix-instantiate.md, and each individual page that includes
-  this also links to nix-build.md for the full explanation.
-->
- A normal filesystem path, like `/home/meow/nixfiles/default.nix`
-  - Or a directory, like `/home/meow/nixfiles`, equivalent to above
- A single lookup path, like `<nixpkgs>` or `<nixos>`
- A URL to a tarball, like `https://github.com/NixOS/nixpkgs/archive/refs/heads/release-23.11.tar.gz`
- A [flakeref](@docroot@/command-ref/new-cli/nix3-flake.md#flake-references), introduced by the prefix `flake:`, like `flake:git+https://git.lix.systems/lix-project/lix`
- A *nixpkgs* channel tarball name, introduced by the prefix `channel:`, like `channel:nixos-unstable`.
-  - This uses a hard-coded URL pattern and is *not* related to the subscribed channels managed by the [nix-channel](@docroot@/command-ref/nix-channel.md) command.
@@ -1,3 +1,23 @@
+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.
@@ -31,23 +51,16 @@ nix3_cli_files = custom_target(

 conf_file_md = custom_target(
  command : [
-    python.full_path(),
-    '@SOURCE_ROOT@/lix/code-generation/build_settings.py',
-    '--kernel', host_machine.system(),
-    '--docs', '@OUTPUT@',
-    '--experimental-features', '@SOURCE_ROOT@/lix/libutil/experimental-features',
-    '@INPUT@',
+    nix_eval_for_docs,
+    '--expr',
+    '(import @INPUT0@).showSettings { inlineHTML = true; } (builtins.fromJSON (builtins.readFile @INPUT1@))',
  ],
+  capture : true,
  input : [
-    libexpr_setting_definitions,
-    libfetchers_setting_definitions,
-    file_transfer_setting_definitions,
-    libstore_setting_definitions,
-    archive_setting_definitions,
-    feature_setting_definitions,
-    logging_setting_definitions,
-    daemon_setting_definitions,
-    develop_settings_definitions,
+    '../../utils.nix',
+    conf_file_json,
+    experimental_features_shortlist_md,
  ],
  output : 'conf-file.md',
+  env : nix_env_for_docs,
 )
@@ -4,7 +4,7 @@

 # Synopsis

-`nix-build` [*fileish…*]
+`nix-build` [*paths…*]
  [`--arg` *name* *value*]
  [`--argstr` *name* *value*]
  [{`--attr` | `-A`} *attrPath*]
@@ -20,55 +20,19 @@ For documentation on the latter, run `nix build --help` or see `man nix3-build`.
 # Description

 The `nix-build` command builds the derivations described by the Nix
-expressions in each *fileish*. If the build succeeds, it places a symlink to
+expressions in *paths*. If the build succeeds, it places a symlink to
 the result in the current directory. The symlink is called `result`. If
 there are multiple Nix expressions, or the Nix expressions evaluate to
 multiple derivations, multiple sequentially numbered symlinks are
 created (`result`, `result-2`, and so on).

-If no *fileish* is specified, then `nix-build` will use `default.nix` in
+If no *paths* are specified, then `nix-build` will use `default.nix` in
 the current directory, if it exists.

-## Fileish Syntax
-
-A given *fileish* may take one of a few different forms, the first being a simple filesystem path, e.g. `nix-build /tmp/some-file.nix`.
-Like the [import builtin](../language/builtins.md#builtins-import) specifying a directory is equivalent to specifying `default.nix` within that directory.
-It may also be a [search path](./env-common.md#env-NIX_PATH) (also known as a lookup path) like `<nixpkgs>`, which is convenient to use with `--attr`/`-A`:
-
-```console
-$ nix-build '<nixpkgs>' -A firefox
-```
-
-(Note the quotation marks around `<nixpkgs>`, which will be necessary in most Unix shells.)
-
-If a *fileish* starts with `http://` or `https://`, it is interpreted as the URL of a tarball which will be fetched and unpacked.
-Lix will then `import` the unpacked directory, so these tarballs must include at least a single top-level directory with a file called `default.nix`
-For example, you could build from a specific version of Nixpkgs with something like:
-
-```console
-$ nix-build "https://github.com/NixOS/nixpkgs/archive/refs/heads/release-23.11.tar.gz" -A firefox
-```
-
-If a path starts with `flake:`, the rest of the argument is interpreted as a [flakeref](./new-cli/nix3-flake.md#flake-references) (see `nix flake --help` or `man nix3-flake`), which requires the "flakes" experimental feature to be enabled.
-Lix will fetch the flake, and then `import` its unpacked directory, so the flake must include a file called `default.nix`.
-For example, the flake analogues to the above `nix-build` commands are:
-
-```console
-$ nix-build flake:nixpkgs -A firefox
-$ nix-build flake:github:NixOS/nixpkgs/release-23.11 -A firefox
-```
-
-Finally, for legacy reasons, if a path starts with `channel:`, the rest of the argument is interpreted as the name of a *nixpkgs* channel tarball to fetch from `https://channels.nixos.org/$CHANNEL_NAME/nixexprs.tar.xz`.
-This is a **hard coded URL** pattern and is *not* related to the subscribed channels managed by the [nix-channel](./nix-channel.md) command.
-
-> **Note**: any of the special syntaxes may always be disambiguated by prefixing the path.
-> For example: a file in the current directory literally called `<nixpkgs>` can be addressed as `./<nixpkgs>`, to escape the special interpretation.
-
-In summary, a path argument may be one of:
-
-{{#include ./fileish-summary.md}}
-
-## Notes
+If an element of *paths* starts with `http://` or `https://`, it is
+interpreted as the URL of a tarball that will be downloaded and unpacked
+to a temporary location. The tarball must include a single top-level
+directory containing at least a file named `default.nix`.

 `nix-build` is essentially a wrapper around
 [`nix-instantiate`](nix-instantiate.md) (to translate a high-level Nix
@@ -11,10 +11,10 @@
 Channels are a mechanism for referencing remote Nix expressions and conveniently retrieving their latest version.

 The moving parts of channels are:
- The official channels listed at <https://channels.nixos.org>
+- The official channels listed at <https://nixos.org/channels>
 - The user-specific list of [subscribed channels](#subscribed-channels)
 - The [downloaded channel contents](#channels)
- The [Nix expression search path](@docroot@/command-ref/conf-file.md#conf-nix-path), set with the [`-I` option](#opt-I) or the [`NIX_PATH` environment variable](#env-NIX_PATH)
+- The [Nix expression search path](@docroot@/command-ref/conf-file.md#conf-nix-path), set with the [`-I` option](#opt-i) or the [`NIX_PATH` environment variable](#env-NIX_PATH)

 > **Note**
 >
@@ -77,9 +77,9 @@ This command has the following operations:
 Subscribe to the Nixpkgs channel and run `hello` from the GNU Hello package:

 ```console
-$ nix-channel --add https://channels.nixos.org/nixpkgs-unstable
+$ nix-channel --add https://nixos.org/channels/nixpkgs-unstable
 $ nix-channel --list
-nixpkgs https://channels.nixos.org/nixpkgs
+nixpkgs https://nixos.org/channels/nixpkgs
 $ nix-channel --update
 $ nix-shell -p hello --run hello
 hello
@@ -36,7 +36,7 @@ Instead, it looks in a few locations, and acts on all profiles it finds there:
   >
   > Not stable; subject to change
   >
-   > Do not rely on this functionality; it just exists for migration purposes and may change in the future.
+   > Do not rely on this functionality; it just exists for migration purposes and is may change in the future.
   > These deprecated paths remain a private implementation detail of Lix.

   <!-- FIXME(Qyriad): this is inconsistent with https://git.lix.systems/lix-project/lix/issues/215, needs updating when that happens -->
@@ -8,7 +8,7 @@
  [`--option` *name* *value*]
  [`--arg` *name* *value*]
  [`--argstr` *name* *value*]
-  [{`--file` | `-f`} *fileish*]
+  [{`--file` | `-f`} *path*]
  [{`--profile` | `-p`} *path*]
  [`--system-filter` *system*]
  [`--dry-run`]
@@ -26,7 +26,7 @@ This operation deletes the specified generations of the current profile.
  >
  > Older *and newer* generations will be deleted by this operation.
  >
-  > One might expect this to just delete older generations than the current one, but that is only true if the current generation is also the latest.
+  > One might expect this to just delete older generations than the curent one, but that is only true if the current generation is also the latest.
  > Because one can roll back to a previous generation, it is possible to have generations newer than the current one.
  > They will also be deleted.

@@ -11,7 +11,6 @@
  [`--from-profile` *path*]
  [`--preserve-installed` | `-P`]
  [`--remove-all` | `-r`]
-  [`--priority` *priority*]

 # Description

@@ -60,11 +59,6 @@ a number of possible ways:
    unambiguous way, which is necessary if there are multiple
    derivations with the same name.

-  - If `--priority` *priority* is given, the priority of the derivations being
-    installed is set to *priority*. This can be used to override the priority of
-    the derivations being installed. This is useful if *args* are store paths,
-    which don't have any priority information.
-
  - If *args* are [store derivations](@docroot@/glossary.md#gloss-store-derivation), then these are
    [realised](@docroot@/command-ref/nix-store/realise.md), and the resulting output paths
    are installed.
@@ -148,8 +142,8 @@ To copy the store path with symbolic name `gcc` from another profile:
 $ nix-env --install --from-profile /nix/var/nix/profiles/foo gcc
 ```

-To install a specific [store derivation](@docroot@/glossary.md#gloss-store-derivation)
-(typically created by `nix-instantiate`):
+To install a specific [store derivation] (typically created by
+`nix-instantiate`):

 ```console
 $ nix-env --install /nix/store/fibjb1bfbpm5mrsxc4mh2d8n37sxh91i-gcc-3.4.3.drv
@@ -2,16 +2,16 @@

 The following options are allowed for all `nix-env` operations, but may not always have an effect.

-  - `--file` / `-f` *fileish*\
+  - `--file` / `-f` *path*\
    Specifies the Nix expression (designated below as the *active Nix
    expression*) used by the `--install`, `--upgrade`, and `--query
    --available` operations to obtain derivations. The default is
    `~/.nix-defexpr`.

-    *fileish* is interpreted the same as with [nix-build](../nix-build.md#fileish-syntax).
-    See that section for complete details (`nix-build --help`), but in summary, a path argument may be one of:
-
-    {{#include ../fileish-summary.md}}
+    If the argument starts with `http://` or `https://`, it is
+    interpreted as the URL of a tarball that will be downloaded and
+    unpacked to a temporary location. The tarball must include a single
+    top-level directory containing at least a file named `default.nix`.

  - `--profile` / `-p` *path*\
    Specifies the profile to be used by those operations that operate on
@@ -22,7 +22,7 @@ left untouched; this is not an error. It is also not an error if an
 element of *args* matches no installed derivations.

 For a description of how *args* is mapped to a set of store paths, see
-[`--install`](install.md). If *args* describes multiple
+[`--install`](#operation---install). If *args* describes multiple
 store paths with the same symbolic name, only the one with the highest
 version is installed.

@@ -5,13 +5,13 @@
 # Synopsis

 `nix-instantiate`
-  [`--parse` | `--eval` [`--strict`] [`--raw`] [`--json`] [`--xml`] ]
+  [`--parse` | `--eval` [`--strict`] [`--json`] [`--xml`] ]
  [`--read-write-mode`]
  [`--arg` *name* *value*]
  [{`--attr`| `-A`} *attrPath*]
  [`--add-root` *path*]
  [`--expr` | `-E`]
-  *fileish…*
+  *files…*

 `nix-instantiate` `--find-file` *files…*

@@ -25,11 +25,8 @@ of the resulting store derivations are printed on standard output.

 [store derivation]: ../glossary.md#gloss-store-derivation

-If *fileish* is the character `-`, then a Nix expression will be read from standard input.
-Otherwise, each *fileish* is interpreted the same as with [nix-build](./nix-build.md#fileish-syntax).
-See that section for complete details (`nix-build --help`), but in summary, a path argument may be one of:
-
-{{#include ./fileish-summary.md}}
+If *files* is the character `-`, then a Nix expression will be read from
+standard input.

 # Options

@@ -38,14 +35,7 @@ See that section for complete details (`nix-build --help`), but in summary, a pa

  - `--parse`\
    Just parse the input files, and print their abstract syntax trees on
-    standard output. The output format of the AST depends on the current
-    internal representation and may change in the future.
-
-    Tooling can use the stderr and exit code of `--parse` to check any
-    Nix code for correctness, but should not rely on stdout without careful
-    versioning. Note that `--parse` also checks for unbound variables.
-    In cases where this is undesired, `with {};` can be prepended
-    to the program to transform all such parse errors into eval errors.
+    standard output as a Nix expression.

  - `--eval`\
    Just parse and evaluate the input files, and print the resulting
@@ -107,27 +97,15 @@ See that section for complete details (`nix-build --help`), but in summary, a pa
    > This option can cause non-termination, because lazy data
    > structures can be infinitely large.

-  - `--raw`\
-    When used with `--eval`, the result must be coercible to a string, i.e.,
-    something that can be converted using `${...}`.
-
-    Integers will always generate an error when output via `--raw`, regardless of
-    [`coerce-integers`](../contributing/experimental-features.md#xp-feature-coerce-integers) being enabled, to avoid ambiguity.
-
-    The output is printed exactly as-is, with no quotes, escaping, or trailing
-    newline.
-
  - `--json`\
    When used with `--eval`, print the resulting value as an JSON
-    representation of the resulting value rather than as a Nix expression.
-
-    The conversion behaviour, if `--strict` is passed, is the same as
-    [`builtins.toJSON`](../language/builtins.md#builtins-toJSON).
+    representation of the abstract syntax tree rather than as a Nix expression.

  - `--xml`\
    When used with `--eval`, print the resulting value as an XML
-    representation of the resulting value rather than as a Nix expression.
-    The schema is the same as that used by [`builtins.toXML`](../language/builtins.md#builtins-toXML).
+    representation of the abstract syntax tree rather than as a Nix expression.
+    The schema is the same as that used by the [`toXML`
+    built-in](../language/builtins.md).

  - `--read-write-mode`\
    When used with `--eval`, perform evaluation in read/write mode so
@@ -33,9 +33,10 @@ the environment of a derivation for development.
 If *path* is not given, `nix-shell` defaults to `shell.nix` if it
 exists, and `default.nix` otherwise.

-If *path* is given it is interpreted like a [*fileish* argument to nix-build](./nix-build.md#fileish-syntax):
-
-{{#include ./fileish-summary.md}}
+If *path* starts with `http://` or `https://`, it is interpreted as the
+URL of a tarball that will be downloaded and unpacked to a temporary
+location. The tarball must include a single top-level directory
+containing at least a file named `default.nix`.

 If the derivation defines the variable `shellHook`, it will be run
 after `$stdenv/setup` has been sourced. Since this hook is not executed
@@ -4,7 +4,7 @@

 # Synopsis

-`nix-store` `--delete` [`--ignore-liveness`] [`--skip-live`] [`--delete-closure`] *paths…*
+`nix-store` `--delete` [`--ignore-liveness`] *paths…*

 # Description

@@ -18,13 +18,6 @@ With the option `--ignore-liveness`, reachability from the roots is
 ignored. However, the path still won’t be deleted if there are other
 paths in the store that refer to it (i.e., depend on it).

-This operation will raise an error if any of the paths are still live
-and `--ignore-liveness` is not passed. Passing `--skip-live` will
-prevent this from being considered an error.
-
-The option `--delete-closure` will also attempt to delete any paths
-that are in the given path's dependency closure.
-
 {{#include ./opt-common.md}}

 {{#include ../opt-common.md}}
@@ -93,12 +93,9 @@ symlink.
    [deriver]: ../../glossary.md#gloss-deriver

  - `--valid-derivers`\
-    Prints the set of all [derivers](../../glossary.md#gloss-deriver) that can be
-    used to build the store paths *paths*.
-    This differs from `--deriver`, which prints the deriver that actually
-    produced *paths*.
-    No deriver may be returned if is not present in the store,
-    eg, if *paths* were substituted from a binary cache.
+    Prints a set of derivation files (`.drv`) which are supposed produce
+    said paths when realized. Might print nothing, for example for source paths
+    or paths subsituted from a binary cache.

  - `--graph`\
    Prints the references graph of the store paths *paths* in the format
@@ -15,6 +15,7 @@ Each of *paths* is processed as follows:
  1. If it is not [valid], substitute the store derivation file itself.
  2. Realise its [output paths]:
    - Try to fetch from [substituters] the [store objects] associated with the output paths in the store derivation's [closure].
+      - With [content-addressed derivations] (experimental): Determine the output paths to realise by querying content-addressed realisation entries in the [Nix database].
    - For any store paths that cannot be substituted, produce the required store objects. This involves first realising all outputs of the derivation's dependencies and then running the derivation's [`builder`](@docroot@/language/derivations.md#attr-builder) executable. <!-- TODO: Link to build process page #8888 -->
 - Otherwise, and if the path is not already valid: Try to fetch the associated [store objects] in the path's [closure] from [substituters].

@@ -27,6 +28,7 @@ If no substitutes are available and no store derivation is given, realisation fa
 [store objects]: @docroot@/glossary.md#gloss-store-object
 [closure]: @docroot@/glossary.md#gloss-closure
 [substituters]: @docroot@/command-ref/conf-file.md#conf-substituters
+[content-addressed derivations]: @docroot@/contributing/experimental-features.md#xp-feature-ca-derivations
 [Nix database]: @docroot@/glossary.md#gloss-nix-database

 The resulting paths are printed on standard output.
@@ -78,16 +78,6 @@ Most commands in Lix accept the following command-line options:

    Display the raw logs, with the progress bar at the bottom.

-  - `multiline`
-
-    Display a progress bar during the builds and in the lines below that one line per activity.
-
-
-  - `multiline-with-logs`
-
-    Display the raw logs, with a progress bar and activities each in a new line at the bottom.
-
-
 - <span id="opt-no-build-output">[`--no-build-output`](#opt-no-build-output)</span> / `-Q`

  By default, output written by builders to standard output and standard error is echoed to the Lix command's standard error.
@@ -661,8 +661,8 @@ Verbosity levels are:

 The default level that the command starts is `ERROR`. The simplest way to
 increase the verbosity by stacking `-v` option (eg: `-vvv == level 3 == INFO`).
-Use `--quiet` to decrease verbosity by one level.
-There is one shortcut, `--debug` to run in `DEBUG` verbosity level.
+There are also two shortcuts, `--debug` to run in `DEBUG` verbosity level and
+`--quiet` to run in `ERROR` verbosity level.

 ----------

@@ -1,37 +0,0 @@
-This section describes the notion of *deprecated features*, and how it fits into the big picture of the development of Lix.
-
-# What are deprecated features?
-
-Deprecated features are disabled by default, with the intent to eventually remove them.
-Users must explicitly enable them to keep using them, by toggling the associated [deprecated feature flags](@docroot@/command-ref/conf-file.md#conf-deprecated-features).
-This allows backwards compatibility and a graceful transition away from undesired features.
-
-# Which features can be deprecated?
-
-Undesired features should be soft-deprecated by yielding a warning when used for a significant amount of time before the can be deprecated.
-Legacy obsolete feature with little to no usage may go through this process faster.
-Deprecated features should have a migration path to a preferred alternative.
-
-# Lifecycle of a deprecated feature
-
-This description is not normative, but a feature removal may roughly happen like this:
-
-1. Add a warning when the feature is being used.
-2. Disable the feature by default, putting it behind a deprecated feature flag.
-  - If disabling the feature started out as an opt-in experimental feature, turn that experimental flag into a no-op or remove it entirely.
-    For example, `--extra-experimental-features=no-url-literals` becomes `--extra-deprecated-features=url-literals`.
-3. Decide on a time frame for how long that feature will still be supported for backwards compatibility, and clearly communicate that in the error messages.
-  - Sometimes, automatic migration to alternatives is possible, and such should be provided if possible
-  - At least one NixOS release cycle should be the minimum
-4. Finally remove the feature entirely, only keeping the error message for those still using it.
-
-# Relation to language versioning
-
-Obviously, removing anything breaks backwards compatibility.
-In an ideal world, we'd have SemVer controls over the language and its features, cleanly allowing us to make breaking changes.
-See https://wiki.lix.systems/books/lix-contributors/page/language-versioning and [RFC 137](https://github.com/nixos/rfcs/pull/137) for efforts on that.
-However, we do not live in such an ideal world, and currently this goal is so far away, that "just disable it with some back-compat for a couple of years" is the most realistic solution, especially for comparatively minor changes.
-
-# Currently available deprecated features
-
-{{#include @generated@/../../../lix/libutil/deprecated-feature-descriptions.md}}
@@ -99,4 +99,4 @@ This means that experimental features and RFCs are orthogonal mechanisms, and ca

 # Currently available experimental features

-{{#include @generated@/../../../lix/libutil/experimental-feature-descriptions.md}}
+{{#include @generated@/contributing/experimental-feature-descriptions.md}}
@@ -11,19 +11,7 @@ The following instructions assume you already have some version of Nix or Lix in

 [installation instructions]: ../installation/installation.md

-A typical development flow for simple changes in Lix looks like:
- [Set up and build Lix](#building)
- For large changes, check in regarding design and possibly create an RFD issue on Forgejo
- Make the changes in your editor
- [Send the changes to Gerrit](#sending-to-gerrit)
- Once you have the number for the CL from Gerrit to put in the changelog, [write a changelog entry](#release-notes) and amend it into the commit
- Update the Gerrit change by submitting it with the same command as the first time
- Request and receive a code review
- Address feedback from the review
- Amend commits, send to Gerrit again
- Submit the approved change
-
-## Building Lix in a development shell {#building}
+## Building Lix in a development shell

 ### Setting up the development shell

@@ -51,30 +39,17 @@ $ nix-shell -A native-clangStdenvPackages

 ### Building from the development shell

-Run a clean build and test with `just clean setup build install test`.
-
-You can also run the unit tests and integration tests separately:
+As always you may run [stdenv's phases by name](https://nixos.org/manual/nixpkgs/unstable/#sec-building-stdenv-package-in-nix-shell), e.g.:

 ```bash
-$ just setup build test-unit
-$ just install test-integration
+$ configurePhase
+$ buildPhase
+$ checkPhase
+$ installPhase
+$ installCheckPhase
 ```

-Many justfile aliases have a `-custom` variant which pass extra arguments to `meson`.
-For example, to work on both Lix and nix-eval-jobs you can run:
-
-```
-$ just setup-custom -Dnix-eval-jobs=enabled
-$ # or
-$ mesonFlags=-Dnix-eval-jobs=enabled just setup
-```
-
-Note that only targets which don't accept extra arguments can be used when
-running multiple targets at once; `just setup build` is fine, but `just
-setup-custom build` is an error. The `test` target is usually the last one to
-run, so it always accepts extra arguments.
-
-You can also build Lix manually:
+To build manually, however, use the following:

 ```bash
 $ meson setup ./build "--prefix=$out" $mesonFlags
@@ -89,7 +64,9 @@ $ meson install -C build
 $ meson test -C build --suite=installcheck
 ```

-In both cases, Lix will be installed to `$PWD/outputs`, the `/bin` of which is prepended to PATH in the development shells.
+(Check and installcheck may both be done after install, allowing you to omit the --suite argument entirely, but this is the order package.nix runs them in.)
+
+This will install Lix to `$PWD/outputs`, the `/bin` of which is prepended to PATH in the development shells.

 If the tests fail and Meson helpfully has no output for why, use the `--print-error-logs` option to `meson test`.

@@ -125,14 +102,14 @@ $ meson compile -C build nixexpr
 All targets may be addressed as their output, relative to the build directory, e.g.:

 ```bash
-$ meson compile -C build lix/libexpr/liblixexpr.so
+$ meson compile -C build src/libexpr/liblixexpr.so
 ```

 But Meson does not consider intermediate files like object files targets.
 To build a specific object file, use Ninja directly and specify the output file relative to the build directory:

 ```bash
-$ ninja -C build lix/libexpr/liblixexpr.so.p/nixexpr.cc.o
+$ ninja -C build src/libexpr/liblixexpr.so.p/nixexpr.cc.o
 ```

 To inspect the canonical source of truth on what the state of the buildsystem configuration is, use:
@@ -141,59 +118,7 @@ To inspect the canonical source of truth on what the state of the buildsystem co
 $ meson introspect
 ```

-#### LLD
-
-The development shell on Linux uses LLD by default for faster link times.
-This is set using `mesonFlags`, so to override it, you can simplify re-specify the linker to Meson:
-
-```bash
-$ just setup-custom -Dc_link_args=-fuse-ld=ld -Dcpp_link_args=-fuse-ld=ld
-```
-
-While using LLD, you may find it helpful to use ThinLTO for even further improvements to link times for incremental builds:
-
-```bash
-$ just setup-custom -Db_lto=true -Db_lto_mode=thin -Db_thinlto_cache=true
-```
-
-## Sending changes to Gerrit for review {#sending-to-gerrit}
-
-We use Gerrit for all our code review in Lix.
-Our instance is at <https://gerrit.lix.systems>.
-
-There's much more information about how to use Gerrit in the [wiki section on Gerrit][wiki-gerrit] including how to use Jujutsu, how to use the UI and more.
-The Snix project also has some Gerrit information [in their contributing docs][snix-gerrit].
-
-[wiki-gerrit]: https://wiki.lix.systems/books/lix-contributors/chapter/gerrit
-[snix-gerrit]: https://snix.dev/docs/guides/contributing/
-
-The gist is that once you have your SSH key and git remote set up, you can send commits for review with:
-
-```
-$ git remote set-url origin ssh://YOURUSERNAME@gerrit.lix.systems:2022/lix
-$ git push origin HEAD:refs/for/main
-```
-
-Then, you can request a review via the "Reply" button on the web UI.
-If you click "Suggest Owners", it will try to suggest the maintainers of the area of the code change to send review requests to.
-Requesting reviews from multiple people is normal.
-
-We do our best to respond to directly sent reviews in a few days, so feel free to request another reviewer or ask on Matrix if you've not got a response for a while.
-Keep in mind that Lix is a volunteer project and we have limited bandwidth, so some changes aren't feasible to shepherd through; please check in on Matrix at design time when doing large changes.
-
-Once you get a `Code-Review+2` vote on your change, it's rebased on `main` and CI marks it `Verified+1`, you're able (and usually expected, so you can have a second chance to check it over) to hit the Submit button to merge it.
-If the change appears as "Rebase Required", you need to rebase it on `main` locally or via the Gerrit UI and wait for `Verified+1` before the Submit button is made active
-The `Code-Review+2` from before will stick around through trivial rebases so no need to re-request review for a mere rebase.
-
-## Interacting with the CI, Buildkite
-
-We use Buildkite for our CI, usually you will not have to interact directly with it other than reviewing any errors it produces, which are linked from Gerrit.
-
-However in certain cases a CI run will fail due to transient issues not related to your code and you will need to rerun it by hand.
-You can log in to the CI via [SSO](https://buildkite.com/sso/lix-project). On your job you can then hit the "Retry failed" button to rerun it, normally you will not have a repeat of the transient issue.
-If the build still fails on CI issues or all builds are failing this should be reported via [Zulip on #T-infra](https://zulip.lix.systems/#narrow/channel/7-T-infra) or [Matrix on #dev](https://matrix.to/#/%23dev%3Alix.systems?via=lix.systems).
-
-## Building Lix with `nix`
+## Building Lix outside of development shells

 To build a release version of Lix for the current operating system and CPU architecture:

@@ -216,7 +141,6 @@ Lix can be built for various platforms, as specified in [`flake.nix`]:

 - `x86_64-linux`
 - `x86_64-darwin`
- `x86_64-freebsd`
 - `i686-linux`
 - `aarch64-linux`
 - `aarch64-darwin`
@@ -244,27 +168,8 @@ or for Nix with the [`flakes`] and [`nix-command`] experimental features enabled
 $ nix build .#packages.aarch64-linux.default
 ```

-### Cross compiling using the Lix flake
-
-Lix can also be easily cross compiled to the following arbitrarily-chosen system doubles, which can be useful for bootstrapping Lix on new platforms.
-These are specified in `crossSystems` in `flake.nix`; feel free to submit changes to add new ones if they are useful to you.
-
- `armv6l-linux`
- `armv7l-linux`
- `aarch64-linux`
- `riscv64-linux`
-
-For example, to cross-compile Lix for `armv6l-linux` from another Linux, use the following:
-
-```console
-$ nix build .#nix-armv6l-linux
-```
-
-It's also possible to cross-compile a tarball of binaries suitable for the Lix installer, for example, for `riscv64-linux`:
-
-```console
-$ nix build .#nix-riscv64-linux.passthru.binaryTarball
-```
+Cross-compiled builds are available for ARMv6 (`armv6l-linux`) and ARMv7 (`armv7l-linux`).
+Add more [system types](#system-type) to `crossSystems` in `flake.nix` to bootstrap Nix on unsupported platforms.

 ### Building for multiple platforms at once

@@ -293,7 +198,7 @@ Lix uses a string with the following format to identify the *system type* or *pl

 It is set when Lix is compiled for the given system, and determined by [Meson's `host_machine.cpu_family()` and `host_machine.system()` values](https://mesonbuild.com/Reference-manual_builtin_host_machine.html).

-For historic reasons and backward-compatibility, some CPU and OS identifiers are translated from the GNU Autotools naming convention in [`meson.build`](https://git.lix.systems/lix-project/lix/src/branch/main/meson.build) as follows:
+For historic reasons and backward-compatibility, some CPU and OS identifiers are translated from the GNU Autotools naming convention in [`meson.build`](https://git.lix.systems/lix-project/lix/blob/main/meson.build) as follows:

 | `host_machine.cpu_family()`             | Nix                 |
 |----------------------------|---------------------|
@@ -320,13 +225,13 @@ To build with one of those environments, you can use
 $ nix build .#nix-ccacheStdenv
 ```

-for <a id="nix-with-flakes">flake-enabled Nix</a>, or
+for flake-enabled Nix, or

 ```console
 $ nix-build --attr nix-ccacheStdenv
 ```

-for <a id="classic-nix">classic Nix</a>.
+for classic Nix.

 You can use any of the other supported environments in place of `nix-ccacheStdenv`.

@@ -350,10 +255,10 @@ Configure your editor to use the `clangd` from the shell, either by running it i
 > Some other editors (e.g. Emacs, Vim) need a plugin to support LSP servers in general (e.g. [lsp-mode](https://github.com/emacs-lsp/lsp-mode) for Emacs and [vim-lsp](https://github.com/prabirshrestha/vim-lsp) for vim).
 > Editor-specific setup is typically opinionated, so we will not cover it here in more detail.

-# Manual and documentation
-
-## Building the manual
+### Checking links in the manual

+The build checks for broken internal links.
+This happens late in the process, so `nix build` is not suitable for iterating.
 To build the manual incrementally, run:

 ```console
@@ -365,25 +270,21 @@ meson compile -C build manual
 [`mdbook-linkcheck`]: https://github.com/Michael-F-Bryan/mdbook-linkcheck
 [URI fragments]: https://en.wikipedia.org/wiki/URI_fragment

-The built manual is in `build/doc/manual/manual/index.html`.
+#### `@docroot@` variable

-The build checks for broken internal links.
-This happens late in the process, so `nix build` is not suitable for iterating and it's recommended to use the `meson` command above instead.
+`@docroot@` provides a base path for links that occur in reusable snippets or other documentation that doesn't have a base path of its own.

-### `@\docroot\@` variable
+If a broken link occurs in a snippet that was inserted into multiple generated files in different directories, use `@docroot@` to reference the `doc/manual/src` directory.

-`@\docroot\@` provides a base path for links that occur in reusable snippets or other documentation that doesn't have a base path of its own.
-
-If a broken link occurs in a snippet that was inserted into multiple generated files in different directories, use `@\docroot\@` to reference the `doc/manual/src` directory.
-
-If the `@\docroot\@` literal appears in an error message from the `mdbook-linkcheck` tool, the `@\docroot\@` replacement needs to be applied to the generated source file that mentions it.
-See existing `@\docroot\@` logic in `doc/manual/substitute.py`.
-Regular markdown files used for the manual have a base path of their own and they can use relative paths instead of `@\docroot\@`.
+If the `@docroot@` literal appears in an error message from the `mdbook-linkcheck` tool, the `@docroot@` replacement needs to be applied to the generated source file that mentions it.
+See existing `@docroot@` logic in the [Makefile].
+Regular markdown files used for the manual have a base path of their own and they can use relative paths instead of `@docroot@`.

 ## API documentation

-Doxygen API documentation will be available online in the future ([tracking issue](https://git.lix.systems/lix-project/lix/issues/422)).
-You can also build and view it yourself:
+Doxygen API documentation is [available
+online](https://hydra.nixos.org/job/nix/master/internal-api-docs/latest/download-by-type/doc/internal-api-docs). You
+can also build and view it yourself:

 ```console
 # nix build .#hydraJobs.internal-api-docs
@@ -393,50 +294,44 @@ You can also build and view it yourself:
 or inside a `nix develop` shell by running:

 ```bash
-$ meson configure build -Dinternal-api-docs=enabled
 $ meson compile -C build internal-api-docs
 $ xdg-open ./outputs/doc/share/doc/nix/internal-api/html/index.html
 ```

 ## Coverage analysis

-A coverage analysis report will be available online in the future (FIXME(lix-hydra)).
-You can build it yourself:
+A coverage analysis report is [available
+online](https://hydra.nixos.org/job/nix/master/coverage/latest/download-by-type/report/coverage). You
+can build it yourself:

 ```
 # nix build .#hydraJobs.coverage
 # xdg-open ./result/coverage/index.html
 ```

-Metrics about the change in line/function coverage over time will be available in the future (FIXME(lix-hydra)).
+Metrics about the change in line/function coverage over time are also
+[available](https://hydra.nixos.org/job/nix/master/coverage#tabs-charts).

-## Add a release note {#release-notes}
+## Add a release note

 `doc/manual/rl-next` contains release notes entries for all unreleased changes.

 User-visible changes should come with a release note.
-Developer-facing changes should have a release note in the Development category if they are significant and if developers should know about them.

 ### Add an entry

-Here's what a complete entry looks like.
-The file name is not incorporated in the final document, and is generally a super brief summary of the change synopsis.
+Here's what a complete entry looks like. The file name is not incorporated in the document.

-```markdown
+```
 ---
 synopsis: Basically a title
 # 1234 or gh#1234 will refer to CppNix GitHub, fj#1234 will refer to a Lix forgejo issue.
 issues: [1234, fj#1234]
-# Use this *only* if there is a CppNix pull request associated with this change.
+# Use this *only* if there is a CppNix pull request associated with this change
 prs: 1238
-# List of Lix Gerrit changelist numbers.
-# If there is an associated Lix GitHub PR, just put in the Gerrit CL number.
+# List of Lix Gerrit changelist numbers; if there is an associated Lix GitHub
+# PR, just put in the Gerrit CL number.
 cls: [123]
-# Heading that this release note will appear under.
-category: Breaking Changes
-# Add a credit mention in the bottom of the release note.
-# your-name is used as a key into doc/manual/change-authors.yml for metadata
-credits: [your-name]
 ---

 Here's one or more paragraphs that describe the change.
@@ -451,105 +346,7 @@ Significant changes should add the following header, which moves them to the top
 significance: significant
 ```

-The following categories of release notes are supported (see `maintainers/build-release-notes.py`):
- Breaking Changes
- Features
- Improvements
- Fixes
- Packaging
- Development
- Miscellany
-
-The `credits` field, if present, gives credit to the author of the patch in the release notes with a message like "Many thanks to (your-name) for this" and linking to GitHub or Forgejo profiles if listed.
-
-If you are forward-porting a change from CppNix, please credit the original author, and optionally credit yourself.
-When adding credits metadata for people external to the project and deciding whether to put in a `display_name`, consider what they are generally known as in the community; even if you know their full name (e.g. from their GitHub profile), we suggest only adding it as a display name if that is what they go by in the community.
-There are multiple reasons we follow this practice, but it boils down to privacy and consent: we would rather not capture full names that are not widely used in the community without the consent of the parties involved, even if they are publicly available.
-As of this writing, the entries with full names as `display_name` are either members of the CppNix team or people who added them themselves.
-
-The names specified in `credits` are used as keys to look up the authorship info in `doc/manual/change-authors.yml`.
-The only mandatory part is that every key appearing in `credits` has an entry present in `change-authors.yml`.
-All of the following properties are optional; you can specify `{}` as the metadata if you want a simple non-hyperlinked mention.
-The following properties are supported:
-
- `display_name`: display name used in place of the key when showing names, if present.
- `forgejo`: Forgejo username. The name in the release notes will be a link to this, if present.
- `github`: GitHub username, used if `forgejo` is not set, again making a link.
-
 ### Build process

 Releases have a precomputed `rl-MAJOR.MINOR.md`, and no `rl-next.md`.
-Development releases have a generated `rl-next.md`.
-
-# Adding experimental or deprecated features, global settings, or builtins
-
-Experimental and deprecated features, global settings, and builtins are generally referenced both in the code and in the documentation.
-To prevent duplication or divergence, they are defined in data files, and a script generates the necessary glue.
-The data file format is similar to the release notes: it consists of a YAML metadata header, followed by the documentation in Markdown format.
-
-## Experimental or deprecated features
-
-Experimental and deprecated features support the following metadata properties:
-* `name` (required): user-facing name of the feature, to be used in `nix.conf` options and on the command line.
-  This should also be the stem of the file name (with extension `md`).
-* `internalName` (required): identifier used to refer to the feature inside the C++ code.
-
-Experimental feature data files should live in `lix/libutil/experimental-features`, and deprecated features in `lix/libutil/deprecated-features`.
-They must be listed in the `experimental_feature_definitions` or `deprecated_feature_definitions` lists in `lix/libutil/meson.build` respectively to be considered by the build system.
-
-## Global settings
-
-Global settings support the following metadata properties:
-* `name` (required): user-facing name of the setting, to be used as key in `nix.conf` and in the `--option` command line argument.
-* `internalName` (required): identifier used to refer to the setting inside the C++ code.
-* `platforms` (optional): a list specifying the platforms on which this setting is available.
-  If not specified, it is available on all platforms.
-  Valid platform names are `darwin`, `linux`.
-* `type` (optional): C++ type of the setting value.
-  This specifies the setting object type as `Setting<T>`; if more control is required, use `settingType` instead.
-* `settingType` (required if `type` is not specified): C++ type of the setting object.
-* `default` (optional): default value of the setting.
-  `null`, truth values, integers, strings and lists are supported as long as the correct YAML type is used, `type` is not taken into account).
-  Other types, machine-dependent values or non-standard representations must be handled using `defaultExpr` and `defaultText` instead.
-* `defaultExpr` (required if `default` is not specified): a string containing the C++ expression representing the default value.
-* `defaultText` (required if `default` is not specified): a string containing the Markdown expression representing the default value in the documentation.
-  Literal values are conventionally surrounded by backticks, and a system-dependent value is signaled by `*machine-specific*`.
-* `aliases` (optional): a list of secondary user-facing names under which the setting is available.
-  Defaults to empty if not specified.
-* `experimentalFeature` (optional): the user-facing name of the experimental feature which needs to be enabled to change the setting.
-  If not specified, no experimental feature is required.
-* `deprecated` (optional): whether the setting is deprecated and shown as such in the documentation for `nix.conf`.
-  Defaults to false if not specified.
-
-Settings are not collected in a single place in the source tree, so an appropriate place needs to be found for the setting to live.
-Look for related setting definition files under second-level subdirectories of `lix` whose name includes `settings`.
-Then add the new file there, and don't forget to register it in the appropriate `meson.build` file.
-
-## Builtin functions
-
-The following metadata properties are supported for builtin functions:
-* `name` (required): the language-facing name (as a member of the `builtins` attribute set) of the function.
-* `implementation` (optional): a C++ expression specifying the implementation of the builtin.
-  It must be a function of signature `void(EvalState &, PosIdx, Value * *, Value &)`.
-  If not specified, defaults to `prim_${name}`.
-* `renameInGlobalScope` (optional): whether the definition should be "hidden" in the global scope by prefixing its name with two underscores.
-  If not specified, defaults to `true`.
-* `args` (required): list containing the names of the arguments, as shown in the documentation.
-  All arguments must be listed here since the function arity is derived as the length of this list.
-* `experimental_feature` (optional): the user-facing name of the experimental feature which needs to be enabled for the builtin function to be available.
-  If not specified, no experimental feature is required.
-
-New builtin function definition files must be added to `lix/libexpr/builtins` and registered in the `builtin_definitions` list in `lix/libexpr/meson.build`.
-
-## Builtin constants
-The following metadata properties are supported for builtin constants:
-* `name` (required): the language-facing name (as a member of the `builtins` attribute set) of the constant.
-* `type` (required): the Nix language type of the constant; the C++ type is automatically derived.
-* `constructorArgs` (optional): list of strings containing C++ expressions passed as arguments to the appropriate `Value` constructor.
-  If the value computation is more complex, `implementation` can be used instead.
-* `implementation` (required if `constructorArgs` is not specified): string containing a C++ expressing computing the value of the constant.
-* `impure` (optional): whether the constant is considered impure.
-  Impure constants are not available when pure evaluation mode is activated.
-  Defaults to `false` when not specified.
-
-New builtin constant definition files must be added to `lix/libexpr/builtin-constants` and registered in the `builtin_constant_definitions` list in `lix/libexpr/meson.build`.
+Set `buildUnreleasedNotes = true;` in `flake.nix` to build the release notes on the fly.
@@ -0,0 +1,15 @@
+# Intermediate step for experimental-feature-descriptions.md.
+# This splorks the output of generate-xp-features.nix as JSON,
+# which gets written as a directory tree below.
+experimental_feature_descriptions_md = custom_target(
+  command : nix_eval_for_docs + [
+    '--expr',
+    'import @INPUT0@ (builtins.fromJSON (builtins.readFile @INPUT1@))',
+  ],
+  input : [
+    '../../generate-xp-features.nix',
+    xp_features_json,
+  ],
+  capture : true,
+  output : 'experimental-feature-descriptions.md',
+)
@@ -13,7 +13,7 @@ The unit tests are defined using the [googletest] and [rapidcheck] frameworks.
 >
 > ```
 > …
-> ├── lix
+> ├── src
 > │   ├── libexpr
 > │   │   ├── …
 > │   │   ├── value
@@ -46,10 +46,10 @@ The unit tests are defined using the [googletest] and [rapidcheck] frameworks.
 > …       …   …   …   …   …
 > ```

-The unit tests for each Lix library (`liblixexpr`, `liblixstore`, etc..) live inside a directory `lix/${library_shortname}/tests` within the directory for the library (`lix/${library_shortname}`).
+The unit tests for each Lix library (`liblixexpr`, `liblixstore`, etc..) live inside a directory `src/${library_shortname}/tests` within the directory for the library (`src/${library_shortname}`).

 The data is in `tests/unit/LIBNAME/data/LIBNAME`, with one subdir per library, with the same name as where the code goes.
-For example, `liblixstore` code is in `lix/libstore`, and its test data is in `tests/unit/libstore/data/libstore`.
+For example, `liblixstore` code is in `src/libstore`, and its test data is in `tests/unit/libstore/data/libstore`.
 The path to the unit test data directory is passed to the unit test executable with the environment variable `_NIX_TEST_UNIT_DATA`.

 ### Running tests
@@ -62,12 +62,6 @@ For `installcheck` specifically, first run `just install` before running the tes

 Finer-grained filtering within a test suite is also possible using the [--gtest_filter](https://google.github.io/googletest/advanced.html#running-a-subset-of-the-tests) command-line option to a test suite executable, or the `GTEST_FILTER` environment variable.

-### Inspecting failures
-
-The test suite emits logs in `build/meson-logs/`; the full textual failure logs are in `build/meson-logs/testlog.txt`.
-
-If you want a much nicer experience of viewing the logs in a structured manner, use `xunit-viewer --results build/meson-logs/testlog.junit.xml --server` to view them in a web browser.
-
 ### Unit test support libraries

 There are headers and code which are not just used to test the library in question, but also downstream libraries.
@@ -253,6 +247,7 @@ To ensure that characterization testing doesn't make it harder to intentionally

 The integration tests are defined in the Nix flake under the `hydraJobs.tests` attribute.
 These tests include everything that needs to interact with external services or run Lix in a non-trivial distributed setup.
+Because these tests are expensive and require more than what the standard github-actions setup provides, they only run on the master branch (on <https://hydra.nixos.org/jobset/nix/master>).

 You can run them manually with `nix build .#hydraJobs.tests.{testName}` or `nix-build -A hydraJobs.tests.{testName}`

@@ -351,7 +346,7 @@ rg '(?:[^A-Za-z]|^)(_[A-Z][^-\[ }/:");$(]+)' -r '$1' --no-filename --only-matchi
 rg '\$\{?([A-Z][^-\[ }/:");]+)' -r '$1' --no-filename --only-matching tests | sort -u > vars.txt
 ```

-I grepped `lix/` for `get[eE]nv\("` to find the mentions in Lix code.
+I grepped `src/` for `get[eE]nv\("` to find the mentions in Lix code.

 ### Used by Lix testing support code

@@ -367,8 +362,8 @@ I grepped `lix/` for `get[eE]nv\("` to find the mentions in Lix code.

 - `_NIX_FORCE_HTTP` - Forces file URIs to be treated as remote ones.

-  Used by `lix/libfetchers/git.cc`, `lix/libstore/http-binary-cache-store.cc`,
-  `lix/libstore/local-binary-cache-store.cc`. Seems to be for forcing Git
+  Used by `src/libfetchers/git.cc`, `src/libstore/http-binary-cache-store.cc`,
+  `src/libstore/local-binary-cache-store.cc`. Seems to be for forcing Git
  clones of `git+file://` URLs, making the HTTP binary
  cache store accept `file://` URLs (presumably passing them to curl?), and
  unknown reasons for the local binary cache.
@@ -380,7 +375,7 @@ I grepped `lix/` for `get[eE]nv\("` to find the mentions in Lix code.
  `structuredAttrs` documentation.
 - `NIX_BIN_DIR`, `NIX_STORE_DIR` (or its inconsistently-used old alias `NIX_STORE`), `NIX_DATA_DIR`,
  `NIX_LOG_DIR`, `NIX_LOG_DIR`, `NIX_STATE_DIR`, `NIX_CONF_DIR` -
-  Overrides compile-time configuration of various locations used by Lix. See `lix/libstore/globals.cc`.
+  Overrides compile-time configuration of various locations used by Lix. See `src/libstore/globals.cc`.

  **Expected value**: a directory
 - `NIX_DAEMON_SOCKET_PATH` (optional) - Overrides the daemon socket path from `$NIX_STATE_DIR/daemon-socket/socket`.
@@ -401,6 +396,7 @@ I grepped `lix/` for `get[eE]nv\("` to find the mentions in Lix code.

  **Expected value**: the path to an executable shell
 - `PRINT_PATH` - Undocumented. Used by `nix-prefetch-url` as an alternative form of `--print-path`. Why???
+- `_NIX_IN_TEST` - If present with any value, makes `fetchClosure` accept file URLs in addition to HTTP ones. Why is this not `_NIX_FORCE_HTTP`??

  Not used anywhere else.
 - `NIX_ALLOW_EVAL` - Used by eval-cache tests to block evaluation if set to `0`.
@@ -432,12 +428,14 @@ I grepped `lix/` for `get[eE]nv\("` to find the mentions in Lix code.
 - `NIX_SHOW_STATS_PATH` - Writes those statistics into a file at the given path instead of stdout. Undocumented.
 - `NIX_SHOW_SYMBOLS` - Dumps the symbol table into the show-stats json output.
 - `TERM` - If `dumb` or unset, disables ANSI colour output.
- `FORCE_COLOR`, `CLICOLOR_FORCE` - Enables ANSI colour output if `NO_COLOR`/`NOCOLOR` not set.
 - `NO_COLOR`, `NOCOLOR` - Disables ANSI colour output.
 - `_NIX_DEVELOPER_SHOW_UNKNOWN_LOCATIONS` - Highlights unknown locations in errors.
 - `NIX_PROFILE` - Selects which profile `nix-env` will operate on. Documented elsewhere.
 - `NIX_SSHOPTS` - Options passed to `ssh(1)` when using a ssh remote store.
  Incorrectly documented on `nix-copy-closure` which is *surely* not the only place they are used??
+- `_NIX_TEST_NO_LSOF` - Used on non-Linux, non-macOS platforms to disable using `lsof` when finding gc roots.
+
+  Since https://git.lix.systems/lix-project/lix/issues/156 was fixed, this should probably just be removed as it was a bad workaround for a macOS issue.
 - `_NIX_TEST_GC_SYNC_1` - Path to a pipe that is used to block the GC briefly to validate invariants from the test suite.
 - `_NIX_TEST_GC_SYNC_2` - Path to a pipe that is used to block the GC briefly to validate invariants from the test suite.
 - `_NIX_TEST_FREE_SPACE_FILE` - Path to a file containing a decimal number with the free space that the GC is to believe it has.
@@ -454,6 +452,9 @@ I grepped `lix/` for `get[eE]nv\("` to find the mentions in Lix code.
 - `NIX_CLIENT_PACKAGE` - Runs the test suite against an alternate Nix client with the current daemon.

  **Expected value**: something like `/nix/store/...-nix-2.18.2`
+- `NIX_TESTS_CA_BY_DEFAULT` - Pass `__contentAddressed`, `outputHashMode` and `outputHashAlgo` to builds of some input-addressed derivations in the test suite.
+
+  **Expected value**: 1
 - `TEST_DATA` - Not an environment variable! This is used in repl characterization tests to refer to `tests/functional/repl_characterization/data`.
  More specifically, that path is replaced with the string `$TEST_DATA` in output for reproducibility.
 - `TEST_HOME` (output) - Set to the temporary directory that is set as `$HOME` inside the tests, underneath `$TEST_ROOT`.
@@ -41,6 +41,12 @@

  [realise]: #gloss-realise

+- [content-addressed derivation]{#gloss-content-addressed-derivation}
+
+  A derivation which has the
+  [`__contentAddressed`](./language/advanced-attributes.md#adv-attr-__contentAddressed)
+  attribute set to `true`.
+
 - [fixed-output derivation]{#gloss-fixed-output-derivation}

  A derivation which includes the
@@ -95,7 +101,7 @@

  See [File System Object](@docroot@/architecture/file-system-object.md) for details.

-  [file system object]: #gloss-store-path
+  [file system object]: #gloss-file-system-object

 - [store object]{#gloss-store-object}

@@ -108,13 +114,14 @@
 - [input-addressed store object]{#gloss-input-addressed-store-object}

  A store object produced by building a
+  non-[content-addressed](#gloss-content-addressed-derivation),
  non-[fixed-output](#gloss-fixed-output-derivation)
  derivation.

 - [output-addressed store object]{#gloss-output-addressed-store-object}

  A [store object] whose [store path] is determined by its contents.
-  This includes derivations and the outputs of [fixed-output derivations](#gloss-fixed-output-derivation).
+  This includes derivations, the outputs of [content-addressed derivations](#gloss-content-addressed-derivation), and the outputs of [fixed-output derivations](#gloss-fixed-output-derivation).

 - [substitute]{#gloss-substitute}

@@ -242,7 +249,7 @@
  links.  NARs are generated and unpacked using `nix-store --dump`
  and `nix-store --restore`.

- [`∅`]{#gloss-empty-set}
+- [`∅`]{#gloss-emtpy-set}

  The empty set symbol. In the context of profile history, this denotes a package is not present in a particular version of the profile.

@@ -1,6 +1,6 @@
 # Installing a Binary Distribution

-See <https://lix.systems/install/> for more details.
+See https://lix.systems/install/ for more details.

 <!--

@@ -60,10 +60,3 @@ Then:
 ```console
 $ docker run -ti lix
 ```
-
-# Known issues
-
-Lix in Docker is very sensitive to **functional** DNS resolution if you are running with [Pasta protections](../advanced-topics/pasta.md) which are enabled by default since Lix 2.93.0 on most distributions.
-If you notice failure to download things, double check whether your **first** DNS entry in `/etc/resolv.conf` is functional.
-
-Lix with [Pasta protections](../advanced-topics/pasta.md) does not support failing over the next entries.
@@ -36,10 +36,7 @@ All users of the Lix daemon may do the following to bring things into the Nix st
    - Input-addressed, so they are run in the sandbox with no network access, with the following exceptions:

      - The (poorly named, since it is not *just* about chroot) property `__noChroot` is set on the derivation and `sandbox` is set to `relaxed`.
-      - On macOS, the derivation property `__darwinAllowLocalNetworking` allows network access to localhost from input-addressed derivations regardless of the `sandbox` setting value.
-        This property exists with such semantics because macOS has no network namespace equivalent to isolate individual processes' localhost networking.
-      - On macOS, the derivation property `__sandboxProfile` accepts extra sandbox profile S-expressions, allowing derivations to bypass arbitrary parts of the sandbox without altogether disabling it.
-        This is only permitted when `sandbox` is set to `relaxed`.
+      - On macOS, the derivation property `__darwinAllowLocalNetworking` allows network access to localhost from input-addressed derivations regardless of the `sandbox` setting value. This property exists with such semantics because macOS has no network namespace equivalent to isolate individual processes' localhost networking.
    - Output-addressed, so they are run with network access but their result must match an expected hash.

  Trusted users may set any setting, including `sandbox = false`, so the sandbox state can be different at runtime from what is described in `nix.conf` for builds invoked with such settings.
@@ -54,6 +54,11 @@ The most current alternative to this section is to read `package.nix` and see wh
    obtained from the its repository
    <https://github.com/troglobit/editline>.

+  - The `libsodium` library for verifying cryptographic signatures
+    of contents fetched from binary caches.
+    It can be obtained from the official web site
+    <https://libsodium.org>.
+
  - Recent versions of Bison and Flex to build the parser. (This is
    because Nix needs GLR support in Bison and reentrancy support in
    Flex.) For Bison, you need version 2.6, which can be obtained from
@@ -148,7 +148,7 @@ paths) are set.

 For example, the following command gets all dependencies of the
 Pan newsreader, as described by [its
-Nix expression](https://github.com/NixOS/nixpkgs/blob/master/pkgs/by-name/pa/pan/package.nix):
+Nix expression](https://github.com/NixOS/nixpkgs/blob/master/pkgs/applications/networking/newsreaders/pan/default.nix):

 ```console
 $ nix-shell '<nixpkgs>' --attr pan
@@ -1 +0,0 @@
-This section lists known issues around Lix.
@@ -1,21 +0,0 @@
-# Limitations of non-isolated builds
-
-## What are non-isolated builds?
-
-In Lix, only builds done on Linux with `sandbox = true` and a functioning
-`pasta-path` are isolated from the rest of the system, all other builds are
-considered non-isolated to some degree.
-
-For example, running Lix with [Pasta](@docroot@/advanced-topics/pasta.md)
-disabled makes the host network visible to fixed-output derivations, reducing
-isolation somewhat.
-
-## Clean termination of non-isolated builds
-
-Non-isolated builds may not terminate cleanly in all cases due to limitations in Lix's process management.
-
-This occurs when a build keeps the build log file descriptor open past the end of the actual build. A common cause of this are background tasks that aren't properly terminated before the main build process exits, for example: HTTP servers run as part of a test suite.
-
-See [issue #1018](https://git.lix.systems/lix-project/lix/issues/1018) for an example.
-
-The only solution is to manually terminate leftover processes in your derivation, including during failure scenarios.
@@ -209,8 +209,15 @@ Derivations can declare some infrequently used optional attributes.

  - [`__contentAddressed`]{#adv-attr-__contentAddressed}
    > **Warning**
-    > This attribute is part of a removed [experimental feature](@docroot@/contributing/experimental-features.md).
-    > Setting this flag *will* cause eval errors.
+    > This attribute is part of an [experimental feature](@docroot@/contributing/experimental-features.md).
+    >
+    > To use this attribute, you must enable the
+    > [`ca-derivations`](@docroot@/contributing/experimental-features.md#xp-feature-ca-derivations) experimental feature.
+    > For example, in [nix.conf](../command-ref/conf-file.md) you could add:
+    >
+    > ```
+    > extra-experimental-features = ca-derivations
+    > ```

    If this attribute is set to `true`, then the derivation
    outputs will be stored in a content-addressed location rather than the
@@ -254,7 +261,7 @@ Derivations can declare some infrequently used optional attributes.
    useful for very trivial derivations (such as `writeText` in Nixpkgs)
    that are cheaper to build than to substitute from a binary cache.

-    You may disable the effects of this attribute by enabling the
+    You may disable the effects of this attibute by enabling the
    `always-allow-substitutes` configuration option in Lix.

    > **Note**
@@ -285,12 +292,6 @@ Derivations can declare some infrequently used optional attributes.
    (associative) arrays. For example, the attribute `hardening.format = true`
    ends up as the Bash associative array element `${hardening[format]}`.

-    > **Warning**
-    >
-    > If set to `true`, other advanced attributes such as [`allowedReferences`](#adv-attr-allowedReferences), [`allowedReferences`](#adv-attr-allowedReferences), [`allowedRequisites`](#adv-attr-allowedRequisites),
-    [`disallowedReferences`](#adv-attr-disallowedReferences) and [`disallowedRequisites`](#adv-attr-disallowedRequisites), maxSize, and maxClosureSize.
-    will have no effect.
-
  - [`outputChecks`]{#adv-attr-outputChecks}\
    When using [structured attributes](#adv-attr-structuredAttrs), the `outputChecks`
    attribute allows defining checks per-output.
@@ -302,6 +303,8 @@ Derivations can declare some infrequently used optional attributes.

    - `maxSize` defines the maximum size of the resulting [store object](../glossary.md#gloss-store-object).
    - `maxClosureSize` defines the maximum size of the output's closure.
+    - `ignoreSelfRefs` controls whether self-references should be considered when
+      checking for allowed references/requisites.

    Example:

@@ -323,6 +326,7 @@ Derivations can declare some infrequently used optional attributes.
    ```

  - [`unsafeDiscardReferences`]{#adv-attr-unsafeDiscardReferences}\
+
    When using [structured attributes](#adv-attr-structuredAttrs), the
    attribute `unsafeDiscardReferences` is an attribute set with a boolean value for each output name.
    If set to `true`, it disables scanning the output for runtime dependencies.
@@ -4,7 +4,7 @@ These constants are built into the Nix language evaluator:

 <dl>

-{{#include @generated@/../../../lix/libexpr/builtin-constants.md}}
+{{#include @generated@/language/builtin-constants.md}}

 </dl>

@@ -15,6 +15,6 @@ For convenience, some built-ins can be accessed directly:
  <dd><p><var>derivation</var> is described in
         <a href="derivations.md">its own section</a>.</p></dd>

-{{#include @generated@/../../../lix/libexpr/builtins.md}}
+{{#include @generated@/language/builtins.md}}

 </dl>
@@ -0,0 +1,27 @@
+builtins_md = custom_target(
+  command : nix_eval_for_docs + [
+    '--expr',
+    'import @INPUT0@ (builtins.fromJSON (builtins.readFile @INPUT1@)).builtins',
+  ],
+  capture : true,
+  input : [
+    '../../generate-builtins.nix',
+    language_json,
+  ],
+  output : 'builtins.md',
+  env : nix_env_for_docs,
+)
+
+builtin_constants_md = custom_target(
+  command : nix_eval_for_docs + [
+    '--expr',
+    'import @INPUT0@ (builtins.fromJSON (builtins.readFile @INPUT1@)).constants',
+  ],
+  capture : true,
+  input : [
+    '../../generate-builtin-constants.nix',
+    language_json,
+  ],
+  output : 'builtin-constants.md',
+  env : nix_env_for_docs,
+)
@@ -26,8 +26,6 @@
 | Logical conjunction (`AND`)            | *bool* `&&` *bool*                         | left          | 12         |
 | Logical disjunction (`OR`)             | *bool* <code>\|\|</code> *bool*            | left          | 13         |
 | [Logical implication]                  | *bool* `->` *bool*                         | none          | 14         |
-| \[Experimental\] [Function piping]     | *expr* `\|>` *func*                        | left          | 15         |
-| \[Experimental\] [Function piping]     | *expr* `<\|` *func*                        | right         | 16         |

 [string]: ./values.md#type-string
 [path]: ./values.md#type-path
@@ -61,10 +59,8 @@ The result is a [Boolean] value.

 ## Arithmetic

-Numbers will retain their type unless mixed with other numeric types:
-Pure integer operations will always return integers, whereas any operation involving at least one floating point number returns a floating point number.
-
-Integer overflow (of 64-bit signed integers) and division by zero are defined to throw an error.
+Numbers are type-compatible:
+Pure integer operations will always return integers, whereas any operation involving at least one floating point number return a floating point number.

 See also [Comparison] and [Equality].

@@ -147,103 +143,21 @@ All comparison operators are implemented in terms of `<`, and the following equi
 | *a* `>`  *b* |       *b* `<` *a*     |
 | *a* `>=` *b* | `! (` *a* `<` *b* `)` |

-Note that the above behaviour violates IEEE 754 for floating point numbers with respect to NaN, for instance.
-This may be fixed in a future major language revision.
-
 [Comparison]: #comparison-operators

 ## Equality

-The following equality comparison rules are followed in order:
-
- Comparisons are first, sometimes, performed by identity (pointer value), and whether or not this occurs varies depending on the context in which the comparison is performed; for example, through `builtins.elem`, comparison of lists, or other cases.
-  The exact instances in which this occurs, aside from direct list and attribute set comparisons as discussed below, are too dependent on implementation details to meaningfully document.
-
-  See [note on identity comparison](#identity-comparison) below.
- Comparisons between a combination of integers and floating point numbers are first converted to floating point then compared as floating point.
- Comparisons between values of differing types, besides the ones mentioned in the above rule, are unequal.
- Strings are compared as their string values, disregarding string contexts.
- Paths are compared as their absolute form (since they are stored as such).
- [Functions][function] are always considered unequal, including with themselves.
- The following are compared in the typical manner:
-  - Integers
-  - Floating point numbers have equality comparison per IEEE 754.
-
-    Note that this means that just like in most languages, floating point arithmetic results are not typically equality comparable, and should instead be compared by checking that the absolute difference is less than some error margin.
-  - Booleans
-  - Null
- [Attribute sets][attribute set] are compared following these rules in order:
-  - If both attribute sets have the same identity (via pointer equality), they are considered equal, regardless of whether the contents have reflexive equality (e.g. even if there are functions contained within).
-
-    See [note on identity comparison](#identity-comparison) below.
-  - If both attribute sets have `type = "derivation"` and have an attribute `outPath` that is equal, they are considered equal.
-
-    This means that two results of `builtins.derivation`, regardless of other things added to their attributes via `//` afterwards (or `passthru` in nixpkgs), will compare equal if they passed the same arguments to `builtins.derivation`.
-  - Otherwise, they are compared element-wise in an unspecified order.
-    Although this order *may* be deterministic in some cases, this is not guaranteed, and correct code must not rely on this ordering behaviour.
-
-    The order determines which elements are evaluated first and thus, if there are throwing values in the attribute set, which of those get evaluated, if any, before the comparison returns an unequal result.
- Lists are compared following these rules in order:
-  - If both lists have the same identity (via pointer equality), they are considered equal, regardless of whether the contents have reflexive equality (e.g. even if there are functions contained within).
-
-    See [note on identity comparison](#identity-comparison) below.
-  - Otherwise, they are compared element-wise in list order.
+- [Attribute sets][attribute set] and [list]s are compared recursively, and therefore are fully evaluated.
+- Comparison of [function]s always returns `false`.
+- Numbers are type-compatible, see [arithmetic] operators.
+- Floating point numbers only differ up to a limited precision.

 [function]: ./constructs.md#functions

 [Equality]: #equality

-### Identity comparison
-
-In the current revision of the Nix language, values are first compared by identity (pointer equality).
-This means that values that are not reflexively equal (that is, they do not satisfy `a == a`), such as functions, are nonetheless sometimes compared as equal with themselves if they are placed in attribute sets or lists, or are compared through other indirect means.
-
-Whether identity comparison applies to a given usage of the language aside from direct list and attribute set comparison is strongly dependent on implementation details to the point it is not feasible to document the exact instances.
-
-This is rather unfortunate behaviour which is regrettably load-bearing on nixpkgs (such as with the `type` attribute of NixOS options) and cannot be changed for the time being.
-It may be changed in a future major language revision.
-
-Correct code must not rely on this behaviour.
-
-For example:
-
-```
-nix-repl> let f = x: 1; s = { func = f; }; in [ (f == f) (s == s) ]
-[ false true ]
-```
-
 ## Logical implication

 Equivalent to `!`*b1* `||` *b2*.

 [Logical implication]: #logical-implication
-
-## \[Experimental\] Function piping
-
-*This language feature is still experimental and may change at any time. Enable `--extra-experimental-features pipe-operator` to use it.*
-
-Pipes are a dedicated operator for function application, but with reverse order and a lower binding strength.
-This allows you to chain function calls together in way that is more natural to read and requires less parentheses.
-
-`a |> f b |> g` is equivalent to `g (f b a)`.
-`g <| f b <| a` is equivalent to `g (f b a)`.
-
-Example code snippet:
-
-```nix
-defaultPrefsFile = defaultPrefs
-  |> lib.mapAttrsToList (
-    key: value: ''
-      // ${value.reason}
-      pref("${key}", ${builtins.toJSON value.value});
-    ''
-  )
-  |> lib.concatStringsSep "\n"
-  |> pkgs.writeText "nixos-default-prefs.js";
-```
-
-Note how `mapAttrsToList` is called with two arguments (the lambda and `defaultPrefs`),
-but moving the last argument in front of the rest improves the reading flow.
-This is common for functions with long first argument, including all `map`-like functions.
-
-[Function piping]: #experimental-function-piping
@@ -7,16 +7,13 @@
  *Strings* can be written in three ways.

  The most common way is to enclose the string between double quotes,
-  e.g., `"foo bar"`. Strings can span multiple lines. The backslash
-  (`\`) can be used to escape characters: newlines, carriage returns
-  and tabs may be written as `\n`, `\r` and `\t` respectively; any
-  other characters can be preceded by a backslash to remove any
-  special meaning they may have, like the special characters `"` and
-  `\` and the character sequence `${`.
+  e.g., `"foo bar"`. Strings can span multiple lines. The special
+  characters `"` and `\` and the character sequence `${` must be
+  escaped by prefixing them with a backslash (`\`). Newlines, carriage
+  returns and tabs can be written as `\n`, `\r` and `\t`,
+  respectively.

  You can include the results of other expressions into a string by enclosing them in `${ }`, a feature known as [string interpolation].
-  Due to a parser issue that has since come to be relied upon, the character sequence `$${` is interpreted literally and does not introduce an interpolation.
-  To express a `$` character immediately followed by an interpolation, the former must be escaped.

  [string interpolation]: ./string-interpolation.md

@@ -46,16 +43,16 @@
  Note that the whitespace and newline following the opening `''` is
  ignored if there is no non-whitespace text on the initial line.

+  Indented strings support [string interpolation].
+
  Since `${` and `''` have special meaning in indented strings, you
  need a way to quote them. `$` can be escaped by prefixing it with
  `''` (that is, two single quotes), i.e., `''$`. `''` can be escaped
-  by prefixing it with `'`, i.e., `'''`. Linefeed, carriage-return and tab
+  by prefixing it with `'`, i.e., `'''`. `$` removes any special
+  meaning from the following `$`. Linefeed, carriage-return and tab
  characters can be written as `''\n`, `''\r`, `''\t`, and `''\`
  escapes any other character.

-  Indented strings support [string interpolation] using `${ }` the same way regular strings do.
-  `$${` is interpreted literally in indented strings as well, so the `$` character must be escaped if it is to be followed by an interpolation.
-
  Indented strings are primarily useful in that they allow multi-line
  string literals to follow the indentation of the enclosing Nix
  expression, and that less escaping is typically necessary for
@@ -77,14 +74,17 @@
  }
  ```

+  Finally, as a convenience, *URIs* as defined in appendix B of
+  [RFC 2396](http://www.ietf.org/rfc/rfc2396.txt) can be written *as
+  is*, without quotes. For instance, the string
+  `"http://example.org/foo.tar.bz2"` can also be written as
+  `http://example.org/foo.tar.bz2`.
+
 - <a id="type-number" href="#type-number">Number</a>

  Numbers, which can be *integers* (like `123`) or *floating point*
  (like `123.43` or `.27e13`).

-  Integers in the Nix language are 64-bit signed integers.
-  Integer overflow is defined to throw an error.
-
  See [arithmetic] and [comparison] operators for semantics.

  [arithmetic]: ./operators.md#arithmetic
@@ -164,7 +164,7 @@ Note that lists are only lazy in values, and they are strict in length.

 An attribute set is a collection of name-value-pairs (called *attributes*) enclosed in curly brackets (`{ }`).

-An attribute name can be an identifier or a [string](#type-string).
+An attribute name can be an identifier or a [string](#string).
 An identifier must start with a letter (`a-z`, `A-Z`) or underscore (`_`), and can otherwise contain letters (`a-z`, `A-Z`), numbers (`0-9`), underscores (`_`), apostrophes (`'`), or dashes (`-`).

 > *name* = *identifier* | *string* \
@@ -5,7 +5,7 @@
 FIXME(Lix): This section does not document the most common modern practices in terms of avoiding channels, pinning, declarative software installation (see flakey-profile or home-manager or NixOS), or using flakes, etc.
 It is, however, likely correct at a technical level.

-For more information on modern practices, see the [resources](https://wiki.lix.systems/books/lix-users/page/nix-resources) page on the Lix site.
+For more information on modern practices, see the [resources](https://lix.systems/resources) page on the Lix site.

 </div>

@@ -41,7 +41,7 @@ install Lix. If this is not the case for some reason, you can add it
 as follows:

 ```console
-$ nix-channel --add https://channels.nixos.org/nixpkgs-unstable
+$ nix-channel --add https://nixos.org/channels/nixpkgs-unstable
 $ nix-channel --update
 ```

@@ -49,7 +49,7 @@ $ nix-channel --update
 >
 > On NixOS, you’re automatically subscribed to a NixOS channel
 > corresponding to your NixOS major release (e.g.
-> <https://channels.nixos.org/nixos-21.11>). A NixOS channel is identical
+> <http://nixos.org/channels/nixos-21.11>). A NixOS channel is identical
 > to the Nixpkgs channel, except that it contains only Linux binaries
 > and is updated only if a set of regression tests succeed.

@@ -126,7 +126,7 @@ $ nix-env --install --attr nixpkgs.subversion
 ```

 will install the package called `subversion` from `nixpkgs` channel (which is, of course, the
-[Subversion version management system](https://subversion.apache.org/)).
+[Subversion version management system](http://subversion.tigris.org/)).

 > **Note**
 >
@@ -71,62 +71,3 @@ $ nix-collect-garbage -d
 ```

 is a quick and easy way to clean up your system.
-
-## Garbage Collector Roots
-
-### Explicit roots
-
-All store paths to which there are symlinks in the directory
-`prefix/nix/var/nix/gcroots` will be used as roots by the garbage
-collector. For instance, the following command makes the path
-`/nix/store/d718ef...-foo` a root of the collector:
-
-```console
-$ ln -s /nix/store/d718ef...-foo /nix/var/nix/gcroots/bar
-```
-
-That is, after this command, the garbage collector will not remove
-`/nix/store/d718ef...-foo` or any of its dependencies.
-
-Subdirectories of `prefix/nix/var/nix/gcroots` are also searched for
-symlinks.
-
-Symlinks may also point to paths outside the nix store. If the
-destination of the symlink is itself a symlink to a store path, it
-is also considered a root. This style of GC root is called an
-"indirect root", and is created by tools like `nix-build` to avoid
-garbage-collecting paths that are being used on-the-fly rather than
-installed in profiles.
-
-
-### In-use roots
-
-Lix will also perform a best-effort detection of paths that are in use
-by running processes when scanning for garbage collection roots, to
-avoid removing paths that are still needed by running processes.
-
-Exact details vary between platforms, but the following will generally
-be taken into account:
-
- Executables in the store that are currently running;
- Other files in the store that are mapped into a process's address space (e.g. shared libraries);
- Files in the store to which processes have open handles;
- Store paths found in processes' environment variables.
-
-Note that this detection is susceptible to missing paths that may still be in use for multiple reasons:
-
- Time-of-check-to-time-of-use (TOCTTOU): new processes may appear
-  after Lix has enumerated the currently running processes, and will
-  not be taken into account;
- Access privileges: if the garbage collection is not running as the
-  root user (this is typically the case for single-user
-  installations), it will not be able to scan processes belonging to
-  other users;
- Other types of references: store paths may be stored in parts of the
-  filesystem (e.g. databases) or process memory (e.g. environment
-  variables changed since the start of the process) that Lix does not
-  scan.
-
-For this reason, it is recommended to create explicit roots whenever
-using store paths that aren't obtained from some existing explicit GC
-root.
@@ -0,0 +1,18 @@
+# Garbage Collector Roots
+
+The roots of the garbage collector are all store paths to which there
+are symlinks in the directory `prefix/nix/var/nix/gcroots`. For
+instance, the following command makes the path
+`/nix/store/d718ef...-foo` a root of the collector:
+
+```console
+$ ln -s /nix/store/d718ef...-foo /nix/var/nix/gcroots/bar
+```
+
+That is, after this command, the garbage collector will not remove
+`/nix/store/d718ef...-foo` or any of its dependencies.
+
+Subdirectories of `prefix/nix/var/nix/gcroots` are also searched for
+symlinks. Symlinks to non-store paths are followed and searched for
+roots, but symlinks to non-store paths *inside* the paths reached in
+that way are not followed to prevent infinite recursion.
@@ -2,8 +2,18 @@

 For historical reasons, [derivations](@docroot@/glossary.md#gloss-store-derivation) are stored on-disk in [ATerm](https://homepages.cwi.nl/~daybuild/daily-books/technology/aterm-guide/aterm-guide.html) format.

-Derivations are serialised in the following format:
+Derivations are serialised in one of the following formats:

-```
-Derive(...)
-```
+- ```
+  Derive(...)
+  ```
+
+  For all stable derivations.
+
+- ```
+  DrvWithVersion(<version-string>, ...)
+  ```
+
+  The only `version-string`s that are in use today are for [experimental features](@docroot@/contributing/experimental-features.md):
+
+  - `"xp-dyn-drv"` for the [`dynamic-derivations`](@docroot@/contributing/experimental-features.md#xp-feature-dynamic-derivations) experimental feature.
@@ -13,7 +13,7 @@

 - The `discard-references` feature has been stabilized.
  This means that the
-  `unsafeDiscardReferences`
+  [unsafeDiscardReferences](@docroot@/contributing/experimental-features.md#xp-feature-discard-references)
  attribute is no longer guarded by an experimental flag and can be used
  freely.

--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Jade Lovelace	5bf891b15a	release: 2.90.0 "Vanilla Ice Cream" Release produced with releng/create_release.xsh Change-Id: Ice53891cdeafff04bd6537be66e8cd6b7dd9678c	2024-07-10 08:40:42 -07:00
Raito Bezariusandjade	f72153a510	doc/release-notes: add date for major release Change-Id: I93aab93c069bb3989c3f8d17e0862899e6f76865 Signed-off-by: Raito Bezarius <raito@lix.systems>	2024-07-10 15:35:00 +00:00
Raito Bezarius	8da08ab551	version: finalize 2.90.0 Tested by Raito, pennae and time. It looks in good shape. Change-Id: I32492557361888c28fe40553c699833876a1deab Signed-off-by: Raito Bezarius <raito@lix.systems>	2024-07-10 15:32:19 +02:00
Jade Lovelace	98d0249d5c	releng: fix broken manifest from 2.90-rc1 Well that is embarrassing. I think the proper thing is to just quickly ship a -rc2, so I will open a backport of this. $ curl https://releases.lix.systems/manifest.nix # This file was generated by releng/create_release.xsh in Lix { aarch64-linux = "/nix/store/mrbknq000af7iaqhk53bnpk1fvfrc1xp-lix-2.90.0-rc1"; aarch64-darwin = "/nix/store/z1bdccwsk34iv491aygh0mm1lgpf7yy1-lix-2.90.0-rc1"; x86_64-darwin = "/nix/store/xqvfpdhzck44v6kyhgi9f8v0xybksb6a-lix-2.90.0-rc1"; x86_64-linux = "/nix/store/h2ml0nx4477r84y82jgm8y80jpr72gqw-lix-release-tarballs"; } Change-Id: I9cf007c850c2faf995a3a9d92457517b8501d1a1	2024-06-16 19:06:45 -07:00
				`@@ -1 +0,0 @@`
				`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.`
				`@@ -1 +0,0 @@`
				`This section lists known issues around Lix.`