Merge remote-tracking branch 'detsys/detsys-main' into lazy-trees-v2

.github/CODEOWNERS

@@ -1,26 +0,0 @@
-# Pull requests concerning the listed files will automatically invite the respective maintainers as reviewers.
-# This file is not used for denoting any kind of ownership, but is merely a tool for handling notifications.
-#
-# Merge permissions are required for maintaining an entry in this file.
-# For documentation on this mechanism, see https://help.github.com/articles/about-codeowners/
-
-# Default reviewers if nothing else matches
-* @edolstra
-
-# This file
-.github/CODEOWNERS @edolstra
-
-# Documentation of built-in functions
-src/libexpr/primops.cc @roberth @fricklerhandwerk
-
-# Documentation of settings
-src/libexpr/eval-settings.hh @fricklerhandwerk
-src/libstore/globals.hh @fricklerhandwerk
-
-# Documentation
-doc/manual @fricklerhandwerk
-maintainers/*.md @fricklerhandwerk
-src/**/*.md @fricklerhandwerk
-
-# Libstore layer
-/src/libstore @ericson2314

.github/ISSUE_TEMPLATE/bug_report.md

@@ -1,10 +1,9 @@
 ---
 name: Bug report
 about: Report unexpected or incorrect behaviour
-title: ''
+title: ""
 labels: bug
-assignees: ''
+assignees: ""
-
 ---
 
 ## Describe the bug
@@ -32,7 +31,9 @@ assignees: ''
 
 ## Metadata
 
-<!-- Please insert the output of running `nix-env --version` below this line -->
+<!-- Please insert the output of running `determinate-nixd version` below this line -->
+
+<!-- Please insert the output of running `nix --version` below this line -->
 
 ## Additional context
 
@@ -42,13 +43,9 @@ assignees: ''
 
 <!-- make sure this issue is not redundant or obsolete -->
 
-- [ ] checked [latest Nix manual] \([source])
+- [ ] checked [latest Determinate Nix manual] \([source])
 - [ ] checked [open bug issues and pull requests] for possible duplicates
 
-[latest Nix manual]: https://nixos.org/manual/nix/unstable/
+[latest Determinate Nix manual]: https://manual.determinate.systems/
-[source]: https://github.com/NixOS/nix/tree/master/doc/manual/source
+[source]: https://github.com/DeterminateSystems/nix-src/tree/detsys-main/doc/manual/source
-[open bug issues and pull requests]: https://github.com/NixOS/nix/labels/bug
+[open bug issues and pull requests]: https://github.com/DeterminateSystems/nix-src/labels/bug
-
----
-
-Add :+1: to [issues you find important](https://github.com/NixOS/nix/issues?q=is%3Aissue+is%3Aopen+sort%3Areactions-%2B1-desc).

.github/ISSUE_TEMPLATE/feature_request.md

@@ -1,10 +1,9 @@
 ---
 name: Feature request
 about: Suggest a new feature
-title: ''
+title: ""
 labels: feature
-assignees: ''
+assignees: ""
-
 ---
 
 ## Is your feature request related to a problem?
@@ -27,13 +26,9 @@ assignees: ''
 
 <!-- make sure this issue is not redundant or obsolete -->
 
-- [ ] checked [latest Nix manual] \([source])
+- [ ] checked [latest Determinate Nix manual] \([source])
-- [ ] checked [open feature issues and pull requests] for possible duplicates
+- [ ] checked [open bug issues and pull requests] for possible duplicates
 
-[latest Nix manual]: https://nixos.org/manual/nix/unstable/
+[latest Determinate Nix manual]: https://manual.determinate.systems/
-[source]: https://github.com/NixOS/nix/tree/master/doc/manual/source
+[source]: https://github.com/DeterminateSystems/nix-src/tree/detsys-main/doc/manual/source
-[open feature issues and pull requests]: https://github.com/NixOS/nix/labels/feature
+[open bug issues and pull requests]: https://github.com/DeterminateSystems/nix-src/labels/bug
-
----
-
-Add :+1: to [issues you find important](https://github.com/NixOS/nix/issues?q=is%3Aissue+is%3Aopen+sort%3Areactions-%2B1-desc).

.github/ISSUE_TEMPLATE/installer.md

@@ -1,18 +1,17 @@
 ---
 name: Installer issue
 about: Report problems with installation
-title: ''
+title: ""
 labels: installer
-assignees: ''
+assignees: ""
-
 ---
 
 ## Platform
 
-<!-- select the platform on which you tried to install Nix -->
+<!-- select the platform on which you tried to install Determinate Nix -->
 
-- [ ] Linux: <!-- state your distribution, e.g. Arch Linux, Ubuntu, ... -->
 - [ ] macOS
+- [ ] Linux: <!-- state your distribution, e.g. Arch Linux, Ubuntu, ... -->
 - [ ] WSL
 
 ## Additional information
@@ -35,13 +34,9 @@ assignees: ''
 
 <!-- make sure this issue is not redundant or obsolete -->
 
-- [ ] checked [latest Nix manual] \([source])
+- [ ] checked [latest Determinate Nix manual] \([source])
-- [ ] checked [open installer issues and pull requests] for possible duplicates
+- [ ] checked [open bug issues and pull requests] for possible duplicates
 
-[latest Nix manual]: https://nixos.org/manual/nix/unstable/
+[latest Determinate Nix manual]: https://manual.determinate.systems/
-[source]: https://github.com/NixOS/nix/tree/master/doc/manual/source
+[source]: https://github.com/DeterminateSystems/nix-src/tree/detsys-main/doc/manual/source
-[open installer issues and pull requests]: https://github.com/NixOS/nix/labels/installer
+[open bug issues and pull requests]: https://github.com/DeterminateSystems/nix-src/labels/bug
-
----
-
-Add :+1: to [issues you find important](https://github.com/NixOS/nix/issues?q=is%3Aissue+is%3Aopen+sort%3Areactions-%2B1-desc).

.github/ISSUE_TEMPLATE/missing_documentation.md

@@ -1,10 +1,9 @@
 ---
 name: Missing or incorrect documentation
 about: Help us improve the reference manual
-title: ''
+title: ""
 labels: documentation
-assignees: ''
+assignees: ""
-
 ---
 
 ## Problem
@@ -19,13 +18,9 @@ assignees: ''
 
 <!-- make sure this issue is not redundant or obsolete -->
 
-- [ ] checked [latest Nix manual] \([source])
+- [ ] checked [latest Determinate Nix manual] \([source])
-- [ ] checked [open documentation issues and pull requests] for possible duplicates
+- [ ] checked [open bug issues and pull requests] for possible duplicates
 
-[latest Nix manual]: https://nixos.org/manual/nix/unstable/
+[latest Determinate Nix manual]: https://manual.determinate.systems/
-[source]: https://github.com/NixOS/nix/tree/master/doc/manual/source
+[source]: https://github.com/DeterminateSystems/nix-src/tree/detsys-main/doc/manual/source
-[open documentation issues and pull requests]: https://github.com/NixOS/nix/labels/documentation
+[open bug issues and pull requests]: https://github.com/DeterminateSystems/nix-src/labels/bug
-
----
-
-Add :+1: to [issues you find important](https://github.com/NixOS/nix/issues?q=is%3Aissue+is%3Aopen+sort%3Areactions-%2B1-desc).

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,22 +1,3 @@
-<!--
-
-IMPORTANT
-
-Nix is a non-trivial project, so for your contribution to be successful,
-it really is important to follow the contributing guidelines:
-
-https://github.com/NixOS/nix/blob/master/CONTRIBUTING.md
-
-Even if you've contributed to open source before, take a moment to read it,
-so you understand the process and the expectations.
-
-- what information to include in commit messages
-- proper attribution
-- volunteering contributions effectively
-- how to get help and our review process.
-
--->
-
 ## Motivation
 
 <!-- Briefly explain what the change is about and why it is desirable. -->
@@ -30,9 +11,3 @@ so you understand the process and the expectations.
 <!-- Invasive change: Discuss alternative designs or approaches you considered. -->
 
 <!-- Large change: Provide instructions to reviewers how to read the diff. -->
-
----
-
-Add :+1: to [pull requests you find important](https://github.com/NixOS/nix/pulls?q=is%3Aopen+sort%3Areactions-%2B1-desc).
-
-The Nix maintainer team uses a [GitHub project board](https://github.com/orgs/NixOS/projects/19) to [schedule and track reviews](https://github.com/NixOS/nix/tree/master/maintainers#project-board-protocol). 

.github/STALE-BOT.md

@@ -2,34 +2,21 @@
 
 - Thanks for your contribution!
 - To remove the stale label, just leave a new comment.
-- _How to find the right people to ping?_ → [`git blame`](https://git-scm.com/docs/git-blame) to the rescue! (or GitHub's history and blame buttons.)
+- You can always ask for help on [Discord](https://determinate.systems/discord).
-- You can always ask for help on [our Discourse Forum](https://discourse.nixos.org/) or on [Matrix - #nix:nixos.org](https://matrix.to/#/#nix:nixos.org).
 
 ## Suggestions for PRs
 
-1. GitHub sometimes doesn't notify people who commented / reviewed a PR previously, when you (force) push commits. If you have addressed the reviews you can [officially ask for a review](https://docs.github.com/en/free-pro-team@latest/github/collaborating-with-issues-and-pull-requests/requesting-a-pull-request-review) from those who commented to you or anyone else.
+1. If it is unfinished but you plan to finish it, please mark it as a draft.
-2. If it is unfinished but you plan to finish it, please mark it as a draft.
+1. If you don't expect to work on it any time soon, closing it with a short comment may encourage someone else to pick up your work.
-3. If you don't expect to work on it any time soon, closing it with a short comment may encourage someone else to pick up your work.
+1. To get things rolling again, rebase the PR against the target branch and address valid comments.
-4. To get things rolling again, rebase the PR against the target branch and address valid comments.
+1. If you need a review to move forward, ask in [Discord](https://determinate.systems/discord).
-5. If you need a review to move forward, ask in [the Discourse thread for PRs that need help](https://discourse.nixos.org/t/prs-in-distress/3604).
-6. If all you need is a merge, check the git history to find and [request reviews](https://docs.github.com/en/github/collaborating-with-issues-and-pull-requests/requesting-a-pull-request-review) from people who usually merge related contributions.
 
 ## Suggestions for issues
 
 1. If it is resolved (either for you personally, or in general), please consider closing it.
 2. If this might still be an issue, but you are not interested in promoting its resolution, please consider closing it while encouraging others to take over and reopen an issue if they care enough.
-3. If you still have interest in resolving it, try to ping somebody who you believe might have an interest in the topic. Consider discussing the problem in [our Discourse Forum](https://discourse.nixos.org/).
+3. If you still have interest in resolving it, try to ping somebody who you believe might have an interest in the topic. Consider discussing the problem in [Discord](https://determinate.systems/discord).
-4. As with all open source projects, your best option is to submit a Pull Request that addresses this issue. We :heart: this attitude!
 
 **Memorandum on closing issues**
 
 Don't be afraid to close an issue that holds valuable information. Closed issues stay in the system for people to search, read, cross-reference, or even reopen--nothing is lost! Closing obsolete issues is an important way to help maintainers focus their time and effort.
-
-## Useful GitHub search queries
-
-- [Open PRs with any stale-bot interaction](https://github.com/NixOS/nix/pulls?q=is%3Apr+is%3Aopen+commenter%3Aapp%2Fstale+)
-- [Open PRs with any stale-bot interaction and `stale`](https://github.com/NixOS/nix/pulls?q=is%3Apr+is%3Aopen+commenter%3Aapp%2Fstale+label%3A%22stale%22)
-- [Open PRs with any stale-bot interaction and NOT `stale`](https://github.com/NixOS/nix/pulls?q=is%3Apr+is%3Aopen+commenter%3Aapp%2Fstale+-label%3A%22stale%22+)
-- [Open Issues with any stale-bot interaction](https://github.com/NixOS/nix/issues?q=is%3Aissue+is%3Aopen+commenter%3Aapp%2Fstale+)
-- [Open Issues with any stale-bot interaction and `stale`](https://github.com/NixOS/nix/issues?q=is%3Aissue+is%3Aopen+commenter%3Aapp%2Fstale+label%3A%22stale%22+)
-- [Open Issues with any stale-bot interaction and NOT `stale`](https://github.com/NixOS/nix/issues?q=is%3Aissue+is%3Aopen+commenter%3Aapp%2Fstale+-label%3A%22stale%22+)

.github/release-notes.sh

@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+
+# SC2002 disables "useless cat" warnings.
+# I prefer pipelines that start with an explicit input, and go from there.
+# Overly fussy.
+# shellcheck disable=SC2002
+
+scratch=$(mktemp -d -t tmp.XXXXXXXXXX)
+finish() {
+  rm -rf "$scratch"
+}
+trap finish EXIT
+
+DATE=$(date +%Y-%m-%d)
+DETERMINATE_NIX_VERSION=$(cat .version-determinate)
+TAG_NAME="v${DETERMINATE_NIX_VERSION}"
+NIX_VERSION=$(cat .version)
+NIX_VERSION_MAJOR_MINOR=$(echo "$NIX_VERSION" | cut -d. -f1,2)
+GITHUB_REPOSITORY="${GITHUB_REPOSITORY:-DeterminateSystems/nix-src}"
+
+gh api "/repos/${GITHUB_REPOSITORY}/releases/generate-notes" \
+        -f "tag_name=${TAG_NAME}" > "$scratch/notes.json"
+
+trim_trailing_newlines() {
+    local text
+    text="$(cat)"
+    echo -n "${text//$'\n'}"
+}
+
+linkify_gh() {
+    sed \
+        -e 's!\(https://github.com/DeterminateSystems/nix-src/\(pull\|issue\)/\([[:digit:]]\+\)\)![DeterminateSystems/nix-src#\3](\1)!' \
+        -e 's#\(https://github.com/DeterminateSystems/nix-src/compare/\([^ ]\+\)\)#[\2](\1)#'
+}
+
+(
+    cat doc/manual/source/release-notes-determinate/changes.md \
+        | sed 's/^.*\(<!-- differences -->\)$/This section lists the differences between upstream Nix '"$NIX_VERSION_MAJOR_MINOR"' and Determinate Nix '"$DETERMINATE_NIX_VERSION"'.\1/' \
+
+    printf "\n<!-- Determinate Nix version %s -->\n" "$DETERMINATE_NIX_VERSION"
+    cat "$scratch/notes.json" \
+        | jq -r .body \
+        | grep -v '^#' \
+        | grep -v "Full Changelog" \
+        | trim_trailing_newlines \
+        | sed -e 's/^\* /\n* /' \
+        | linkify_gh
+) > "$scratch/changes.md"
+
+(
+    printf "# Release %s (%s)\n\n" \
+        "$DETERMINATE_NIX_VERSION" \
+        "$DATE"
+    printf "* Based on [upstream Nix %s](../release-notes/rl-%s.md).\n\n" \
+        "$NIX_VERSION" \
+        "$NIX_VERSION_MAJOR_MINOR"
+
+    cat "$scratch/notes.json" | jq -r .body | linkify_gh
+) > "$scratch/rl.md"
+
+(
+    cat doc/manual/source/SUMMARY.md.in \
+        | sed 's/\(<!-- next -->\)$/\1\n  - [Release '"$DETERMINATE_NIX_VERSION"' ('"$DATE"')](release-notes-determinate\/rl-'"$DETERMINATE_NIX_VERSION"'.md)/'
+) > "$scratch/summary.md"
+
+mv "$scratch/changes.md" doc/manual/source/release-notes-determinate/changes.md
+mv "$scratch/rl.md" "doc/manual/source/release-notes-determinate/rl-${DETERMINATE_NIX_VERSION}.md"
+mv "$scratch/summary.md" doc/manual/source/SUMMARY.md.in

.github/workflows/build.yml

@@ -37,6 +37,7 @@ jobs:
           path: ./tarball/*.xz
   test:
     if: ${{ inputs.if && inputs.run_tests}}
+    needs: build
     strategy:
       fail-fast: false
     runs-on: ${{ inputs.os }}

.github/workflows/propose-release.yml

@@ -26,4 +26,6 @@ jobs:
       extra-commands-early: |
         echo ${{ inputs.version }} > .version-determinate
         git add .version-determinate
+        ./.github/release-notes.sh
+        git add doc
         git commit -m "Set .version-determinate to ${{ inputs.version }}" || true

.version

@@ -1 +1 @@
-2.28.2
+2.28.3

.version-determinate

@@ -1 +1 @@
-3.3.1
+3.4.2

doc/manual/source/SUMMARY.md.in

@@ -127,7 +127,9 @@
   - [Experimental Features](development/experimental-features.md)
   - [Contributing](development/contributing.md)
 - [Determinate Nix Release Notes](release-notes-determinate/index.md)
-  - [Changes between Nix and Determinate Nix](release-notes-determinate/changes.md)
+  - [Changes between Nix and Determinate Nix](release-notes-determinate/changes.md)<!-- next -->
+  - [Release 3.4.2 (2025-05-05)](release-notes-determinate/rl-3.4.2.md)
+  - [Release 3.4.0 (2025-04-25)](release-notes-determinate/rl-3.4.0.md)
   - [Release 3.3.0 (2025-04-11)](release-notes-determinate/rl-3.3.0.md)
   - [Release 3.1.0 (2025-03-27)](release-notes-determinate/rl-3.1.0.md)
   - [Release 3.0.0 (2025-03-04)](release-notes-determinate/rl-3.0.0.md)

doc/manual/source/command-ref/nix-channel.md

@@ -8,6 +8,12 @@
 
 # Description
 
+> **Warning**
+>
+> nix-channel is deprecated in favor of flakes in Determinate Nix.
+> For a guide on Nix flakes, see: <https://zero-to-nix.com/>.
+> For details and to offer feedback on the deprecation process, see: <https://github.com/DeterminateSystems/nix-src/issues/34>.
+
 Channels are a mechanism for referencing remote Nix expressions and conveniently retrieving their latest version.
 
 The moving parts of channels are:

doc/manual/source/release-notes-determinate/changes.md

@@ -1,6 +1,6 @@
 # Changes between Nix and Determinate Nix
 
-This section lists the differences between upstream Nix 2.24 and Determinate Nix 3.3.0.
+This section lists the differences between upstream Nix 2.28 and Determinate Nix 3.4.2.<!-- differences -->
 
 * In Determinate Nix, flakes are stable. You no longer need to enable the `flakes` experimental feature.
 
@@ -9,3 +9,11 @@ This section lists the differences between upstream Nix 2.24 and Determinate Nix
 * Determinate Nix has a setting [`json-log-path`](@docroot@/command-ref/conf-file.md#conf-json-log-path) to send a copy of all Nix log messages (in JSON format) to a file or Unix domain socket.
 
 * Determinate Nix has made `nix profile install` an alias to `nix profile add`, a more symmetrical antonym of `nix profile remove`.
+
+* `nix-channel` and `channel:` url syntax (like `channel:nixos-24.11`) is deprecated, see: https://github.com/DeterminateSystems/nix-src/issues/34
+
+* Using indirect flake references and implicit inputs is deprecated, see: https://github.com/DeterminateSystems/nix-src/issues/37
+
+* Warnings around "dirty trees" are updated to reduce "dirty" jargon, and now refers to "uncommitted changes".
+
+<!-- Determinate Nix version 3.4.2 -->

doc/manual/source/release-notes-determinate/rl-3.4.0.md

@@ -0,0 +1,50 @@
+# Release 3.4.0 (2025-04-25)
+
+* Based on [upstream Nix 2.28.2](../release-notes/rl-2.28.md).
+
+* **Warn users that `nix-channel` is deprecated.**
+
+This is the first change accomplishing our roadmap item of deprecating Nix channels: https://github.com/DeterminateSystems/nix-src/issues/34
+
+This is due to user confusion and surprising behavior of channels, especially in the context of user vs. root channels.
+
+The goal of this change is to make the user experience of Nix more predictable.
+In particular, these changes are to support users with lower levels of experience who are following guides that focus on channels as the mechanism of distribution.
+
+Users will now see this message:
+
+> nix-channel is deprecated in favor of flakes in Determinate Nix. For a guide on Nix flakes, see: https://zero-to-nix.com/.  or details and to offer feedback on the deprecation process, see: https://github.com/DeterminateSystems/nix-src/issues/34.
+
+
+* **Warn users that `channel:` URLs are deprecated.**
+
+This is the second change regarding our deprecation of Nix channels.
+Using a `channel:` URL (like `channel:nixos-24.11`) will yield a warning like this:
+
+> Channels are deprecated in favor of flakes in Determinate Nix. Instead of 'channel:nixos-24.11', use 'https://nixos.org/channels/nixos-24.11/nixexprs.tar.xz'. For a guide on Nix flakes, see: https://zero-to-nix.com/. For details and to offer feedback on the deprecation process, see: https://github.com/DeterminateSystems/nix-src/issues/34.
+
+* **Warn users against indirect flake references in `flake.nix` inputs**
+
+This is the first change accomplishing our roadmap item of deprecating implicit and indirect flake inputs: https://github.com/DeterminateSystems/nix-src/issues/37
+
+The flake registry provides an important UX affordance for using Nix flakes and remote sources in command line uses.
+For that reason, the registry is not being deprecated entirely and will still be used for command-line incantations, like nix run.
+
+This move will eliminate user confusion and surprising behavior around global and local registries during flake input resolution.
+
+The goal of this change is to make the user experience of Nix more predictable.
+We have seen a pattern of confusion when using automatic flake inputs and local registries.
+Specifically, users' flake inputs resolving and locking inconsistently depending on the configuration of the host system.
+
+Users will now see the following warning if their flake.nix uses an implicit or indirect Flake reference input:
+
+> Flake input 'nixpkgs' uses the flake registry. Using the registry in flake inputs is deprecated in Determinate Nix. To make your flake future-proof, add the following to 'xxx/flake.nix':
+>
+>  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.11";
+>
+> For more information, see: https://github.com/DeterminateSystems/nix-src/issues/37
+
+
+### Other updates:
+* Improve the "dirty tree" message. Determinate Nix will now say `Git tree '...' has uncommitted changes` instead of `Git tree '...' is dirty`
+* Stop warning about uncommitted changes in a Git repository when using `nix develop`

doc/manual/source/release-notes-determinate/rl-3.4.2.md

@@ -0,0 +1,4 @@
+# Release 3.4.2 (2025-05-05)
+
+* Based on [upstream Nix 2.28.3](../release-notes/rl-2.28.md).
+

flake.nix

@@ -142,14 +142,15 @@
           # without "polluting" the top level "`pkgs`" attrset.
           # This also has the benefit of providing us with a distinct set of packages
           # we can iterate over.
-          nixComponents =
+          # The `2` suffix is here because otherwise it interferes with `nixVersions.latest`, which is used in daemon compat tests.
+          nixComponents2 =
             lib.makeScopeWithSplicing'
               {
                 inherit (final) splicePackages;
-                inherit (final.nixDependencies) newScope;
+                inherit (final.nixDependencies2) newScope;
               }
               {
-                otherSplices = final.generateSplicesForMkScope "nixComponents";
+                otherSplices = final.generateSplicesForMkScope "nixComponents2";
                 f = import ./packaging/components.nix {
                   inherit (final) lib;
                   inherit officialRelease;
@@ -160,22 +161,23 @@
               };
 
           # The dependencies are in their own scope, so that they don't have to be
-          # in Nixpkgs top level `pkgs` or `nixComponents`.
+          # in Nixpkgs top level `pkgs` or `nixComponents2`.
-          nixDependencies =
+          # The `2` suffix is here because otherwise it interferes with `nixVersions.latest`, which is used in daemon compat tests.
+          nixDependencies2 =
             lib.makeScopeWithSplicing'
               {
                 inherit (final) splicePackages;
-                inherit (final) newScope; # layered directly on pkgs, unlike nixComponents above
+                inherit (final) newScope; # layered directly on pkgs, unlike nixComponents2 above
               }
               {
-                otherSplices = final.generateSplicesForMkScope "nixDependencies";
+                otherSplices = final.generateSplicesForMkScope "nixDependencies2";
                 f = import ./packaging/dependencies.nix {
                   inherit inputs stdenv;
                   pkgs = final;
                 };
               };
 
-          nix = final.nixComponents.nix-cli;
+          nix = final.nixComponents2.nix-cli;
 
           # See https://github.com/NixOS/nixpkgs/pull/214409
           # Remove when fixed in this flake's nixpkgs
@@ -275,7 +277,7 @@
                 # memory leaks with detect_leaks=0.
                 "" = rec {
                   nixpkgs = nixpkgsFor.${system}.native;
-                  nixComponents = nixpkgs.nixComponents.overrideScope (
+                  nixComponents = nixpkgs.nixComponents2.overrideScope (
                     nixCompFinal: nixCompPrev: {
                       mesonComponentOverrides = _finalAttrs: prevAttrs: {
                         mesonFlags =
@@ -303,7 +305,7 @@
               nixpkgsPrefix:
               {
                 nixpkgs,
-                nixComponents ? nixpkgs.nixComponents,
+                nixComponents ? nixpkgs.nixComponents2,
               }:
               flatMapAttrs nixComponents (
                 pkgName: pkg:
@@ -333,9 +335,9 @@
           binaryTarball = self.hydraJobs.binaryTarball.${system};
           # TODO probably should be `nix-cli`
           nix = self.packages.${system}.nix-everything;
-          nix-manual = nixpkgsFor.${system}.native.nixComponents.nix-manual;
+          nix-manual = nixpkgsFor.${system}.native.nixComponents2.nix-manual;
-          nix-internal-api-docs = nixpkgsFor.${system}.native.nixComponents.nix-internal-api-docs;
+          nix-internal-api-docs = nixpkgsFor.${system}.native.nixComponents2.nix-internal-api-docs;
-          nix-external-api-docs = nixpkgsFor.${system}.native.nixComponents.nix-external-api-docs;
+          nix-external-api-docs = nixpkgsFor.${system}.native.nixComponents2.nix-external-api-docs;
 
           fallbackPathsNix =
             let
@@ -421,7 +423,7 @@
               }:
               {
                 # These attributes go right into `packages.<system>`.
-                "${pkgName}" = nixpkgsFor.${system}.native.nixComponents.${pkgName};
+                "${pkgName}" = nixpkgsFor.${system}.native.nixComponents2.${pkgName};
               }
               // lib.optionalAttrs supportsCross (
                 flatMapAttrs (lib.genAttrs crossSystems (_: { })) (
@@ -429,7 +431,7 @@
                   { }:
                   {
                     # These attributes go right into `packages.<system>`.
-                    "${pkgName}-${crossSystem}" = nixpkgsFor.${system}.cross.${crossSystem}.nixComponents.${pkgName};
+                    "${pkgName}-${crossSystem}" = nixpkgsFor.${system}.cross.${crossSystem}.nixComponents2.${pkgName};
                   }
                 )
               )
@@ -439,7 +441,7 @@
                 {
                   # These attributes go right into `packages.<system>`.
                   "${pkgName}-${stdenvName}" =
-                    nixpkgsFor.${system}.nativeForStdenv.${stdenvName}.nixComponents.${pkgName};
+                    nixpkgsFor.${system}.nativeForStdenv.${stdenvName}.nixComponents2.${pkgName};
                 }
               )
             )

maintainers/flake-module.nix

@@ -172,14 +172,14 @@
               ''^src/libfetchers/include/nix/fetchers/tarball\.hh$''
               ''^src/libfetchers/git\.cc$''
               ''^src/libfetchers/mercurial\.cc$''
-              ''^src/libflake/flake/config\.cc$''
+              ''^src/libflake/config\.cc$''
-              ''^src/libflake/flake/flake\.cc$''
+              ''^src/libflake/flake\.cc$''
               ''^src/libflake/include/nix/flake/flake\.hh$''
-              ''^src/libflake/flake/flakeref\.cc$''
+              ''^src/libflake/flakeref\.cc$''
               ''^src/libflake/include/nix/flake/flakeref\.hh$''
-              ''^src/libflake/flake/lockfile\.cc$''
+              ''^src/libflake/lockfile\.cc$''
               ''^src/libflake/include/nix/flake/lockfile\.hh$''
-              ''^src/libflake/flake/url-name\.cc$''
+              ''^src/libflake/url-name\.cc$''
               ''^src/libmain/common-args\.cc$''
               ''^src/libmain/include/nix/main/common-args\.hh$''
               ''^src/libmain/loggers\.cc$''

packaging/dev-shell.nix

@@ -5,11 +5,11 @@
 
 { pkgs }:
 
-pkgs.nixComponents.nix-util.overrideAttrs (
+pkgs.nixComponents2.nix-util.overrideAttrs (
   attrs:
 
   let
-    stdenv = pkgs.nixDependencies.stdenv;
+    stdenv = pkgs.nixDependencies2.stdenv;
     buildCanExecuteHost = stdenv.buildPlatform.canExecute stdenv.hostPlatform;
     modular = devFlake.getSystem stdenv.buildPlatform.system;
     transformFlag =
@@ -79,26 +79,26 @@ pkgs.nixComponents.nix-util.overrideAttrs (
     };
 
     mesonFlags =
-      map (transformFlag "libutil") (ignoreCrossFile pkgs.nixComponents.nix-util.mesonFlags)
+      map (transformFlag "libutil") (ignoreCrossFile pkgs.nixComponents2.nix-util.mesonFlags)
-      ++ map (transformFlag "libstore") (ignoreCrossFile pkgs.nixComponents.nix-store.mesonFlags)
+      ++ map (transformFlag "libstore") (ignoreCrossFile pkgs.nixComponents2.nix-store.mesonFlags)
-      ++ map (transformFlag "libfetchers") (ignoreCrossFile pkgs.nixComponents.nix-fetchers.mesonFlags)
+      ++ map (transformFlag "libfetchers") (ignoreCrossFile pkgs.nixComponents2.nix-fetchers.mesonFlags)
       ++ lib.optionals havePerl (
-        map (transformFlag "perl") (ignoreCrossFile pkgs.nixComponents.nix-perl-bindings.mesonFlags)
+        map (transformFlag "perl") (ignoreCrossFile pkgs.nixComponents2.nix-perl-bindings.mesonFlags)
       )
-      ++ map (transformFlag "libexpr") (ignoreCrossFile pkgs.nixComponents.nix-expr.mesonFlags)
+      ++ map (transformFlag "libexpr") (ignoreCrossFile pkgs.nixComponents2.nix-expr.mesonFlags)
-      ++ map (transformFlag "libcmd") (ignoreCrossFile pkgs.nixComponents.nix-cmd.mesonFlags);
+      ++ map (transformFlag "libcmd") (ignoreCrossFile pkgs.nixComponents2.nix-cmd.mesonFlags);
 
     nativeBuildInputs =
       attrs.nativeBuildInputs or [ ]
-      ++ pkgs.nixComponents.nix-util.nativeBuildInputs
+      ++ pkgs.nixComponents2.nix-util.nativeBuildInputs
-      ++ pkgs.nixComponents.nix-store.nativeBuildInputs
+      ++ pkgs.nixComponents2.nix-store.nativeBuildInputs
-      ++ pkgs.nixComponents.nix-fetchers.nativeBuildInputs
+      ++ pkgs.nixComponents2.nix-fetchers.nativeBuildInputs
-      ++ pkgs.nixComponents.nix-expr.nativeBuildInputs
+      ++ pkgs.nixComponents2.nix-expr.nativeBuildInputs
-      ++ lib.optionals havePerl pkgs.nixComponents.nix-perl-bindings.nativeBuildInputs
+      ++ lib.optionals havePerl pkgs.nixComponents2.nix-perl-bindings.nativeBuildInputs
-      ++ lib.optionals buildCanExecuteHost pkgs.nixComponents.nix-manual.externalNativeBuildInputs
+      ++ lib.optionals buildCanExecuteHost pkgs.nixComponents2.nix-manual.externalNativeBuildInputs
-      ++ pkgs.nixComponents.nix-internal-api-docs.nativeBuildInputs
+      ++ pkgs.nixComponents2.nix-internal-api-docs.nativeBuildInputs
-      ++ pkgs.nixComponents.nix-external-api-docs.nativeBuildInputs
+      ++ pkgs.nixComponents2.nix-external-api-docs.nativeBuildInputs
-      ++ pkgs.nixComponents.nix-functional-tests.externalNativeBuildInputs
+      ++ pkgs.nixComponents2.nix-functional-tests.externalNativeBuildInputs
       ++ lib.optional (
         !buildCanExecuteHost
         # Hack around https://github.com/nixos/nixpkgs/commit/bf7ad8cfbfa102a90463433e2c5027573b462479
@@ -123,14 +123,14 @@ pkgs.nixComponents.nix-util.overrideAttrs (
 
     buildInputs =
       attrs.buildInputs or [ ]
-      ++ pkgs.nixComponents.nix-util.buildInputs
+      ++ pkgs.nixComponents2.nix-util.buildInputs
-      ++ pkgs.nixComponents.nix-store.buildInputs
+      ++ pkgs.nixComponents2.nix-store.buildInputs
-      ++ pkgs.nixComponents.nix-store-tests.externalBuildInputs
+      ++ pkgs.nixComponents2.nix-store-tests.externalBuildInputs
-      ++ pkgs.nixComponents.nix-fetchers.buildInputs
+      ++ pkgs.nixComponents2.nix-fetchers.buildInputs
-      ++ pkgs.nixComponents.nix-expr.buildInputs
+      ++ pkgs.nixComponents2.nix-expr.buildInputs
-      ++ pkgs.nixComponents.nix-expr.externalPropagatedBuildInputs
+      ++ pkgs.nixComponents2.nix-expr.externalPropagatedBuildInputs
-      ++ pkgs.nixComponents.nix-cmd.buildInputs
+      ++ pkgs.nixComponents2.nix-cmd.buildInputs
-      ++ lib.optionals havePerl pkgs.nixComponents.nix-perl-bindings.externalBuildInputs
+      ++ lib.optionals havePerl pkgs.nixComponents2.nix-perl-bindings.externalBuildInputs
       ++ lib.optional havePerl pkgs.perl;
   }
 )

packaging/hydra.nix

@@ -19,14 +19,14 @@ let
 
   testNixVersions =
     pkgs: daemon:
-    pkgs.nixComponents.nix-functional-tests.override {
+    pkgs.nixComponents2.nix-functional-tests.override {
       pname = "nix-daemon-compat-tests";
       version = "${pkgs.nix.version}-with-daemon-${daemon.version}";
 
       test-daemon = daemon;
     };
 
-  # Technically we could just return `pkgs.nixComponents`, but for Hydra it's
+  # Technically we could just return `pkgs.nixComponents2`, but for Hydra it's
   # convention to transpose it, and to transpose it efficiently, we need to
   # enumerate them manually, so that we don't evaluate unnecessary package sets.
   # See listingIsComplete below.
@@ -85,7 +85,7 @@ in
       } (_: null);
       actualPkgs = lib.concatMapAttrs (
         k: v: if lib.strings.hasPrefix "nix-" k then { ${k} = null; } else { }
-      ) nixpkgsFor.${arbitrarySystem}.native.nixComponents;
+      ) nixpkgsFor.${arbitrarySystem}.native.nixComponents2;
       diff = lib.concatStringsSep "\n" (
         lib.concatLists (
           lib.mapAttrsToList (
@@ -111,7 +111,7 @@ in
 
   # Binary package for various platforms.
   build = forAllPackages (
-    pkgName: forAllSystems (system: nixpkgsFor.${system}.native.nixComponents.${pkgName})
+    pkgName: forAllSystems (system: nixpkgsFor.${system}.native.nixComponents2.${pkgName})
   );
 
   shellInputs = removeAttrs (forAllSystems (
@@ -119,7 +119,7 @@ in
   )) [ "i686-linux" ];
 
   # Perl bindings for various platforms.
-  perlBindings = forAllSystems (system: nixpkgsFor.${system}.native.nixComponents.nix-perl-bindings);
+  perlBindings = forAllSystems (system: nixpkgsFor.${system}.native.nixComponents2.nix-perl-bindings);
 
   # Binary tarball for various platforms, containing a Nix store
   # with the closure of 'nix' package, and the second half of
@@ -145,13 +145,13 @@ in
   # };
 
   # Nix's manual
-  manual = nixpkgsFor.x86_64-linux.native.nixComponents.nix-manual;
+  manual = nixpkgsFor.x86_64-linux.native.nixComponents2.nix-manual;
 
   # API docs for Nix's unstable internal C++ interfaces.
-  internal-api-docs = nixpkgsFor.x86_64-linux.native.nixComponents.nix-internal-api-docs;
+  internal-api-docs = nixpkgsFor.x86_64-linux.native.nixComponents2.nix-internal-api-docs;
 
   # API docs for Nix's C bindings.
-  external-api-docs = nixpkgsFor.x86_64-linux.native.nixComponents.nix-external-api-docs;
+  external-api-docs = nixpkgsFor.x86_64-linux.native.nixComponents2.nix-external-api-docs;
 
   # System tests.
   tests =

src/libcmd/include/nix/cmd/command.hh

@@ -214,6 +214,8 @@ struct InstallableCommand : virtual Args, SourceExprCommand
 {
     InstallableCommand();
 
+    virtual void preRun(ref<Store> store);
+
     virtual void run(ref<Store> store, ref<Installable> installable) = 0;
 
     void run(ref<Store> store) override;

src/libcmd/installables.cc

@@ -40,7 +40,7 @@ void completeFlakeInputAttrPath(
     std::string_view prefix)
 {
     for (auto & flakeRef : flakeRefs) {
-        auto flake = flake::getFlake(*evalState, flakeRef, true);
+        auto flake = flake::getFlake(*evalState, flakeRef, fetchers::UseRegistries::All);
         for (auto & input : flake.inputs)
             if (hasPrefix(input.first, prefix))
                 completions.add(input.first);
@@ -903,8 +903,13 @@ InstallableCommand::InstallableCommand()
     });
 }
 
+void InstallableCommand::preRun(ref<Store> store)
+{
+}
+
 void InstallableCommand::run(ref<Store> store)
 {
+    preRun(store);
     auto installable = parseInstallable(store, _installable);
     run(store, std::move(installable));
 }

src/libexpr/eval-settings.cc

@@ -84,9 +84,17 @@ bool EvalSettings::isPseudoUrl(std::string_view s)
 
 std::string EvalSettings::resolvePseudoUrl(std::string_view url)
 {
-    if (hasPrefix(url, "channel:"))
+    if (hasPrefix(url, "channel:")) {
-        return "https://nixos.org/channels/" + std::string(url.substr(8)) + "/nixexprs.tar.xz";
+        auto realUrl = "https://nixos.org/channels/" + std::string(url.substr(8)) + "/nixexprs.tar.xz";
-    else
+        static bool haveWarned = false;
+        warnOnce(haveWarned,
+            "Channels are deprecated in favor of flakes in Determinate Nix. "
+            "Instead of '%s', use '%s'. "
+            "See https://zero-to-nix.com for a guide to Nix flakes. "
+            "For details and to offer feedback on the deprecation process, see: https://github.com/DeterminateSystems/nix-src/issues/34.",
+            url, realUrl);
+        return realUrl;
+    } else
         return std::string(url);
 }
 
@@ -103,4 +111,4 @@ Path getNixDefExpr()
         : getHome() + "/.nix-defexpr";
 }
 
-} // namespace nix
+} // namespace nix

src/libexpr/primops/fetchTree.cc

@@ -179,7 +179,7 @@ static void fetchTree(
     }
 
     if (!state.settings.pureEval && !input.isDirect())
-        input = lookupInRegistries(state.store, input).first;
+        input = lookupInRegistries(state.store, input, fetchers::UseRegistries::Limited).first;
 
     if (state.settings.pureEval && !input.isLocked()) {
         if (input.getNarHash())
@@ -202,7 +202,7 @@ static void fetchTree(
             throw Error("input '%s' is not allowed to use the '__final' attribute", input.to_string());
     }
 
-    auto cachedInput = state.inputCache->getAccessor(state.store, input, false);
+    auto cachedInput = state.inputCache->getAccessor(state.store, input, fetchers::UseRegistries::No);
 
     auto storePath = state.mountInput(cachedInput.lockedInput, input, cachedInput.accessor, true);
 

src/libfetchers/git.cc

@@ -393,10 +393,10 @@ struct GitInputScheme : InputScheme
         {
             if (workdirInfo.isDirty) {
                 if (!settings.allowDirty)
-                    throw Error("Git tree '%s' is dirty", locationToArg());
+                    throw Error("Git tree '%s' has uncommitted changes", locationToArg());
 
                 if (settings.warnDirty)
-                    warn("Git tree '%s' is dirty", locationToArg());
+                    warn("Git tree '%s' has uncommitted changes", locationToArg());
             }
         }
 

src/libfetchers/include/nix/fetchers/input-cache.hh

@@ -2,6 +2,8 @@
 
 namespace nix::fetchers {
 
+enum class UseRegistries : int;
+
 struct InputCache
 {
     struct CachedResult
@@ -11,7 +13,7 @@ struct InputCache
         Input lockedInput;
     };
 
-    CachedResult getAccessor(ref<Store> store, const Input & originalInput, bool useRegistries);
+    CachedResult getAccessor(ref<Store> store, const Input & originalInput, UseRegistries useRegistries);
 
     struct CachedInput
     {
@@ -26,6 +28,8 @@ struct InputCache
     virtual void clear() = 0;
 
     static ref<InputCache> create();
+
+    virtual ~InputCache() = default;
 };
 
 }

src/libfetchers/include/nix/fetchers/registry.hh

@@ -65,7 +65,11 @@ void overrideRegistry(
     const Input & to,
     const Attrs & extraAttrs);
 
-using RegistryFilter = std::function<bool(Registry::RegistryType)>;
+enum class UseRegistries : int {
+    No,
+    All,
+    Limited, // global and flag registry only
+};
 
 /**
  * Rewrite a flakeref using the registries. If `filter` is set, only
@@ -74,6 +78,6 @@ using RegistryFilter = std::function<bool(Registry::RegistryType)>;
 std::pair<Input, Attrs> lookupInRegistries(
     ref<Store> store,
     const Input & input,
-    const RegistryFilter & filter = {});
+    UseRegistries useRegistries);
 
 }

src/libfetchers/input-cache.cc

@@ -5,7 +5,8 @@
 
 namespace nix::fetchers {
 
-InputCache::CachedResult InputCache::getAccessor(ref<Store> store, const Input & originalInput, bool useRegistries)
+InputCache::CachedResult
+InputCache::getAccessor(ref<Store> store, const Input & originalInput, UseRegistries useRegistries)
 {
     auto fetched = lookup(originalInput);
     Input resolvedInput = originalInput;
@@ -15,13 +16,8 @@ InputCache::CachedResult InputCache::getAccessor(ref<Store> store, const Input &
             auto [accessor, lockedInput] = originalInput.getAccessor(store);
             fetched.emplace(CachedInput{.lockedInput = lockedInput, .accessor = accessor});
         } else {
-            if (useRegistries) {
+            if (useRegistries != fetchers::UseRegistries::No) {
-                auto [res, extraAttrs] =
+                auto [res, extraAttrs] = lookupInRegistries(store, originalInput, useRegistries);
-                    lookupInRegistries(store, originalInput, [](fetchers::Registry::RegistryType type) {
-                        /* Only use the global registry and CLI flags
-                           to resolve indirect flakerefs. */
-                        return type == fetchers::Registry::Flag || type == fetchers::Registry::Global;
-                    });
                 resolvedInput = std::move(res);
                 fetched = lookup(resolvedInput);
                 if (!fetched) {

src/libfetchers/registry.cc

@@ -14,6 +14,8 @@ std::shared_ptr<Registry> Registry::read(
     const Settings & settings,
     const Path & path, RegistryType type)
 {
+    debug("reading registry '%s'", path);
+
     auto registry = std::make_shared<Registry>(settings, type);
 
     if (!pathExists(path))
@@ -179,29 +181,36 @@ Registries getRegistries(const Settings & settings, ref<Store> store)
 std::pair<Input, Attrs> lookupInRegistries(
     ref<Store> store,
     const Input & _input,
-    const RegistryFilter & filter)
+    UseRegistries useRegistries)
 {
     Attrs extraAttrs;
     int n = 0;
     Input input(_input);
 
+    if (useRegistries == UseRegistries::No)
+        return {input, extraAttrs};
+
  restart:
 
     n++;
     if (n > 100) throw Error("cycle detected in flake registry for '%s'", input.to_string());
 
     for (auto & registry : getRegistries(*input.settings, store)) {
-        if (filter && !filter(registry->type)) continue;
+        if (useRegistries == UseRegistries::Limited
+            && !(registry->type == fetchers::Registry::Flag || registry->type == fetchers::Registry::Global))
+            continue;
         // FIXME: O(n)
         for (auto & entry : registry->entries) {
             if (entry.exact) {
                 if (entry.from == input) {
+                    debug("resolved flakeref '%s' against registry %d exactly", input.to_string(), registry->type);
                     input = entry.to;
                     extraAttrs = entry.extraAttrs;
                     goto restart;
                 }
             } else {
                 if (entry.from.contains(input)) {
+                    debug("resolved flakeref '%s' against registry %d", input.to_string(), registry->type);
                     input = entry.to.applyOverrides(
                         !entry.from.getRef() && input.getRef() ? input.getRef() : std::optional<std::string>(),
                         !entry.from.getRev() && input.getRev() ? input.getRev() : std::optional<Hash>());

src/libflake/flake.cc

@@ -321,7 +321,7 @@ static FlakeRef applySelfAttrs(
 static Flake getFlake(
     EvalState & state,
     const FlakeRef & originalRef,
-    bool useRegistries,
+    fetchers::UseRegistries useRegistries,
     const InputAttrPath & lockRootAttrPath,
     bool requireLockable)
 {
@@ -341,7 +341,7 @@ static Flake getFlake(
         debug("refetching input '%s' due to self attribute", newLockedRef);
         // FIXME: need to remove attrs that are invalidated by the changed input attrs, such as 'narHash'.
         newLockedRef.input.attrs.erase("narHash");
-        auto cachedInput2 = state.inputCache->getAccessor(state.store, newLockedRef.input, useRegistries);
+        auto cachedInput2 = state.inputCache->getAccessor(state.store, newLockedRef.input, fetchers::UseRegistries::No);
         cachedInput.accessor = cachedInput2.accessor;
         lockedRef = FlakeRef(std::move(cachedInput2.lockedInput), newLockedRef.subdir);
     }
@@ -353,7 +353,7 @@ static Flake getFlake(
         lockRootAttrPath);
 }
 
-Flake getFlake(EvalState & state, const FlakeRef & originalRef, bool useRegistries, bool requireLockable)
+Flake getFlake(EvalState & state, const FlakeRef & originalRef, fetchers::UseRegistries useRegistries, bool requireLockable)
 {
     return getFlake(state, originalRef, useRegistries, {}, requireLockable);
 }
@@ -376,8 +376,15 @@ LockedFlake lockFlake(
     const LockFlags & lockFlags)
 {
     auto useRegistries = lockFlags.useRegistries.value_or(settings.useRegistries);
+    auto useRegistriesTop = useRegistries ? fetchers::UseRegistries::All : fetchers::UseRegistries::No;
+    auto useRegistriesInputs = useRegistries ? fetchers::UseRegistries::Limited : fetchers::UseRegistries::No;
 
-    auto flake = getFlake(state, topRef, useRegistries, {}, lockFlags.requireLockable);
+    auto flake = getFlake(
+        state,
+        topRef,
+        useRegistriesTop,
+        {},
+        lockFlags.requireLockable);
 
     if (lockFlags.applyNixConfig) {
         flake.config.apply(settings);
@@ -552,7 +559,12 @@ LockedFlake lockFlake(
                         if (auto resolvedPath = resolveRelativePath()) {
                             return readFlake(state, ref, ref, ref, *resolvedPath, inputAttrPath);
                         } else {
-                            return getFlake(state, ref, useRegistries, inputAttrPath, true);
+                            return getFlake(
+                                state,
+                                ref,
+                                useRegistriesInputs,
+                                inputAttrPath,
+                                true);
                         }
                     };
 
@@ -660,6 +672,29 @@ LockedFlake lockFlake(
                             use --no-write-lock-file. */
                         auto ref = (input2.ref && explicitCliOverrides.contains(inputAttrPath)) ? *input2.ref : *input.ref;
 
+                        /* Warn against the use of indirect flakerefs
+                           (but only at top-level since we don't want
+                           to annoy users about flakes that are not
+                           under their control). */
+                        auto warnRegistry = [&](const FlakeRef & resolvedRef)
+                        {
+                            if (inputAttrPath.size() == 1 && !input.ref->input.isDirect()) {
+                                std::ostringstream s;
+                                printLiteralString(s, resolvedRef.to_string());
+                                warn(
+                                    "Flake input '%1%' uses the flake registry. "
+                                    "Using the registry in flake inputs is deprecated in Determinate Nix. "
+                                    "To make your flake future-proof, add the following to '%2%':\n"
+                                    "\n"
+                                    "  inputs.%1%.url = %3%;\n"
+                                    "\n"
+                                    "For more information, see: https://github.com/DeterminateSystems/nix-src/issues/37",
+                                    inputAttrPathS,
+                                    flake.path,
+                                    s.str());
+                            }
+                        };
+
                         if (input.isFlake) {
                             auto inputFlake = getInputFlake(*input.ref);
 
@@ -691,6 +726,8 @@ LockedFlake lockFlake(
                                 oldLock ? followsPrefix : inputAttrPath,
                                 inputFlake.path,
                                 false);
+
+                            warnRegistry(inputFlake.resolvedRef);
                         }
 
                         else {
@@ -700,10 +737,13 @@ LockedFlake lockFlake(
                                 if (auto resolvedPath = resolveRelativePath()) {
                                     return {*resolvedPath, *input.ref};
                                 } else {
-                                    auto cachedInput = state.inputCache->getAccessor(state.store, input.ref->input, useRegistries);
+                                    auto cachedInput = state.inputCache->getAccessor(state.store, input.ref->input, useRegistriesTop);
 
+                                    auto resolvedRef = FlakeRef(std::move(cachedInput.resolvedInput), input.ref->subdir);
                                     auto lockedRef = FlakeRef(std::move(cachedInput.lockedInput), input.ref->subdir);
 
+                                    warnRegistry(resolvedRef);
+
                                     return {
                                         state.storePath(state.mountInput(lockedRef.input, input.ref->input, cachedInput.accessor, true)),
                                         lockedRef
@@ -817,7 +857,11 @@ LockedFlake lockFlake(
                            repo, so we should re-read it. FIXME: we could
                            also just clear the 'rev' field... */
                         auto prevLockedRef = flake.lockedRef;
-                        flake = getFlake(state, topRef, useRegistries, lockFlags.requireLockable);
+                        flake = getFlake(
+                            state,
+                            topRef,
+                            useRegistriesTop,
+                            lockFlags.requireLockable);
 
                         if (lockFlags.commitLockFile &&
                             flake.lockedRef.input.getRev() &&

src/libflake/flakeref.cc

@@ -37,9 +37,9 @@ std::ostream & operator << (std::ostream & str, const FlakeRef & flakeRef)
 
 FlakeRef FlakeRef::resolve(
     ref<Store> store,
-    const fetchers::RegistryFilter & filter) const
+    fetchers::UseRegistries useRegistries) const
 {
-    auto [input2, extraAttrs] = lookupInRegistries(store, input, filter);
+    auto [input2, extraAttrs] = lookupInRegistries(store, input, useRegistries);
     return FlakeRef(std::move(input2), fetchers::maybeGetStrAttr(extraAttrs, "dir").value_or(subdir));
 }
 

src/libflake/include/nix/flake/flake.hh

@@ -118,7 +118,7 @@ struct Flake
 Flake getFlake(
     EvalState & state,
     const FlakeRef & flakeRef,
-    bool useRegistries,
+    fetchers::UseRegistries useRegistries,
     bool requireLockable = true);
 
 /**

src/libflake/include/nix/flake/flakeref.hh

@@ -65,7 +65,7 @@ struct FlakeRef
 
     FlakeRef resolve(
         ref<Store> store,
-        const fetchers::RegistryFilter & filter = {}) const;
+        fetchers::UseRegistries useRegistries = fetchers::UseRegistries::All) const;
 
     static FlakeRef fromAttrs(
         const fetchers::Settings & fetchSettings,

src/libflake/meson.build

@@ -39,13 +39,13 @@ foreach header : [
 endforeach
 
 sources = files(
-  'flake/config.cc',
+  'config.cc',
-  'flake/flake.cc',
+  'flake.cc',
-  'flake/flakeref.cc',
+  'flakeref.cc',
-  'flake/lockfile.cc',
+  'lockfile.cc',
-  'flake/flake-primops.cc',
+  'flake-primops.cc',
-  'flake/settings.cc',
+  'settings.cc',
-  'flake/url-name.cc',
+  'url-name.cc',
 )
 
 subdir('include/nix/flake')

src/libutil-tests/file-content-address.cc

@@ -1,3 +1,4 @@
+#include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
 #include "nix/util/file-content-address.hh"
@@ -26,8 +27,11 @@ TEST(FileSerialisationMethod, testRoundTripPrintParse_2) {
     }
 }
 
-TEST(FileSerialisationMethod, testParseFileSerialisationMethodOptException) {
+TEST(FileSerialisationMethod, testParseFileSerialisationMethodOptException)
-    EXPECT_THROW(parseFileSerialisationMethod("narwhal"), UsageError);
+{
+    EXPECT_THAT(
+        []() { parseFileSerialisationMethod("narwhal"); },
+        testing::ThrowsMessage<UsageError>(testing::HasSubstr("narwhal")));
 }
 
 /* ----------------------------------------------------------------------------
@@ -54,8 +58,11 @@ TEST(FileIngestionMethod, testRoundTripPrintParse_2) {
     }
 }
 
-TEST(FileIngestionMethod, testParseFileIngestionMethodOptException) {
+TEST(FileIngestionMethod, testParseFileIngestionMethodOptException)
-    EXPECT_THROW(parseFileIngestionMethod("narwhal"), UsageError);
+{
+    EXPECT_THAT(
+        []() { parseFileIngestionMethod("narwhal"); },
+        testing::ThrowsMessage<UsageError>(testing::HasSubstr("narwhal")));
 }
 
 }

src/libutil-tests/monitorfdhup.cc

@@ -1,8 +1,10 @@
-#include "nix/util/util.hh"
+#ifndef _WIN32
-#include "nix/util/monitor-fd.hh"
 
-#include <sys/file.h>
+#  include "nix/util/util.hh"
-#include <gtest/gtest.h>
+#  include "nix/util/monitor-fd.hh"
+
+#  include <sys/file.h>
+#  include <gtest/gtest.h>
 
 namespace nix {
 TEST(MonitorFdHup, shouldNotBlock)
@@ -16,3 +18,5 @@ TEST(MonitorFdHup, shouldNotBlock)
     }
 }
 }
+
+#endif

src/libutil/file-content-address.cc

@@ -22,7 +22,7 @@ FileSerialisationMethod parseFileSerialisationMethod(std::string_view input)
     if (ret)
         return *ret;
     else
-        throw UsageError("Unknown file serialiation method '%s', expect `flat` or `nar`");
+        throw UsageError("Unknown file serialiation method '%s', expect `flat` or `nar`", input);
 }
 
 
@@ -35,7 +35,7 @@ FileIngestionMethod parseFileIngestionMethod(std::string_view input)
         if (ret)
             return static_cast<FileIngestionMethod>(*ret);
         else
-            throw UsageError("Unknown file ingestion method '%s', expect `flat`, `nar`, or `git`");
+            throw UsageError("Unknown file ingestion method '%s', expect `flat`, `nar`, or `git`", input);
     }
 }
 

src/libutil/file-system.cc

@@ -111,7 +111,7 @@ Path canonPath(PathView path, bool resolveSymlinks)
         (std::string & result, std::string_view & remaining) {
             if (resolveSymlinks && fs::is_symlink(result)) {
                 if (++followCount >= maxFollow)
-                    throw Error("infinite symlink recursion in path '%0%'", remaining);
+                    throw Error("infinite symlink recursion in path '%1%'", remaining);
                 remaining = (temp = concatStrings(readLink(result), remaining));
                 if (isAbsolute(remaining)) {
                     /* restart for symlinks pointing to absolute path */

src/libutil/git.cc

@@ -134,7 +134,7 @@ void parseTree(
         RawMode rawMode = std::stoi(perms, 0, 8);
         auto modeOpt = decodeMode(rawMode);
         if (!modeOpt)
-            throw Error("Unknown Git permission: %o", perms);
+            throw Error("Unknown Git permission: %o", rawMode);
         auto mode = std::move(*modeOpt);
 
         std::string name = getStringUntil(source, '\0');

src/libutil/unix/processes.cc

@@ -202,6 +202,7 @@ static int childEntry(void * arg)
 
 pid_t startProcess(std::function<void()> fun, const ProcessOptions & options)
 {
+    auto newLogger = makeSimpleLogger();
     ChildWrapperFunction wrapper = [&] {
         if (!options.allowVfork) {
             /* Set a simple logger, while releasing (not destroying)
@@ -210,7 +211,7 @@ pid_t startProcess(std::function<void()> fun, const ProcessOptions & options)
                ~ProgressBar() tries to join a thread that doesn't
                exist. */
             logger.release();
-            logger = makeSimpleLogger();
+            logger = std::move(newLogger);
         }
         try {
 #ifdef __linux__

src/nix-channel/nix-channel.cc

@@ -164,6 +164,11 @@ static void update(const StringSet & channelNames)
 
 static int main_nix_channel(int argc, char ** argv)
 {
+    warn(
+        "nix-channel is deprecated in favor of flakes in Determinate Nix. \
+See https://zero-to-nix.com for a guide to Nix flakes. \
+For details and to offer feedback on the deprecation process, see: https://github.com/DeterminateSystems/nix-src/issues/34.");
+
     {
         // Figure out the name of the `.nix-channels' file to use
         auto home = getHome();

src/nix/develop.cc

@@ -1,5 +1,6 @@
 #include "nix/util/config-global.hh"
 #include "nix/expr/eval.hh"
+#include "nix/fetchers/fetch-settings.hh"
 #include "nix/cmd/installable-flake.hh"
 #include "nix/cmd/command-installable-value.hh"
 #include "nix/main/common-args.hh"
@@ -583,6 +584,11 @@ struct CmdDevelop : Common, MixEnvironment
           ;
     }
 
+    void preRun(ref<Store> store) override
+    {
+        fetchSettings.warnDirty = false;
+    }
+
     void run(ref<Store> store, ref<Installable> installable) override
     {
         auto [buildEnvironment, gcroot] = getBuildEnvironment(store, installable);

src/nix/package.nix

@@ -1,4 +1,5 @@
 {
+  stdenv,
   lib,
   mkMesonExecutable,
 
@@ -94,6 +95,11 @@ mkMesonExecutable (finalAttrs: {
   mesonFlags = [
   ];
 
+  postInstall = lib.optionalString stdenv.hostPlatform.isStatic ''
+    mkdir -p $out/nix-support
+    echo "file binary-dist $out/bin/nix" >> $out/nix-support/hydra-build-products
+  '';
+
   meta = {
     mainProgram = "nix";
     platforms = lib.platforms.unix ++ lib.platforms.windows;

tests/functional/flakes/flakes.sh

@@ -223,7 +223,7 @@ mv "$registry.tmp" "$registry"
 # Ensure that locking ignores the user registry.
 mkdir -p "$TEST_HOME/.config/nix"
 ln -sfn "$registry" "$TEST_HOME/.config/nix/registry.json"
-nix flake metadata flake1
+nix flake metadata --flake-registry '' flake1
 expectStderr 1 nix flake update --flake-registry '' --flake "$flake3Dir" | grepQuiet "cannot find flake 'flake:flake1' in the flake registries"
 rm "$TEST_HOME/.config/nix/registry.json"
 
@@ -266,6 +266,7 @@ nix registry add user-flake2 "git+file://$percentEncodedFlake2Dir"
 [[ $(nix --flake-registry "" registry list | wc -l) == 2 ]]
 nix --flake-registry "" registry list | grepQuietInverse '^global' # nothing in global registry
 nix --flake-registry "" registry list | grepQuiet '^user'
+nix flake metadata --flake-registry "" user-flake1 | grepQuiet 'URL:.*flake1.*'
 nix registry remove user-flake1
 nix registry remove user-flake2
 [[ $(nix registry list | wc -l) == 4 ]]

tests/nixos/default.nix

@@ -31,7 +31,7 @@ let
         nixpkgs.pkgs = nixpkgsFor.${system}.native;
         nix.checkAllErrors = false;
         # TODO: decide which packaging stage to use. `nix-cli` is efficient, but not the same as the user-facing `everything.nix` package (`default`). Perhaps a good compromise is `everything.nix` + `noTests` defined above?
-        nix.package = nixpkgsFor.${system}.native.nixComponents.nix-cli;
+        nix.package = nixpkgsFor.${system}.native.nixComponents2.nix-cli;
 
         # Evaluate VMs faster
         documentation.enable = false;

tests/nixos/functional/common.nix

@@ -49,11 +49,11 @@ in
 
               cd ~
 
-              cp -r ${pkgs.nixComponents.nix-functional-tests.src} nix
+              cp -r ${pkgs.nixComponents2.nix-functional-tests.src} nix
               chmod -R +w nix
 
               chmod u+w nix/.version
-              echo ${pkgs.nixComponents.version} > nix/.version
+              echo ${pkgs.nixComponents2.version} > nix/.version
 
               export isTestOnNixOS=1