DeterminateSystems · cole-h · Jul 9, 2025 · May 23, 2025 · May 23, 2025 · May 23, 2025
diff --git a/.gitignore b/.gitignore
@@ -47,3 +47,6 @@ result-*
 .DS_Store
 
 flake-regressions
+
+# direnv
+.direnv/
diff --git a/.mergify.yml b/.mergify.yml
@@ -139,3 +139,14 @@ pull_request_rules:
         labels:
           - automatic backport
           - merge-queue
+
+  - name: backport patches to 2.29
+    conditions:
+      - label=backport 2.29-maintenance
+    actions:
+      backport:
+        branches:
+          - "2.29-maintenance"
+        labels:
+          - automatic backport
+          - merge-queue
diff --git a/.version b/.version
@@ -1 +1 @@
-2.29.1
+2.30.0
diff --git a/doc/manual/source/SUMMARY.md.in b/doc/manual/source/SUMMARY.md.in
@@ -52,6 +52,7 @@
   - [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)
+  - [Evaluation profiler](advanced-topics/eval-profiler.md)
 - [Command Reference](command-ref/index.md)
   - [Common Options](command-ref/opt-common.md)
   - [Common Environment Variables](command-ref/env-common.md)
@@ -147,6 +148,7 @@
   - [Release 3.0.0 (2025-03-04)](release-notes-determinate/rl-3.0.0.md)
 - [Nix Release Notes](release-notes/index.md)
 {{#include ./SUMMARY-rl-next.md}}
+  - [Release 2.30 (2025-07-07)](release-notes/rl-2.30.md)
   - [Release 2.29 (2025-05-14)](release-notes/rl-2.29.md)
   - [Release 2.28 (2025-04-02)](release-notes/rl-2.28.md)
   - [Release 2.27 (2025-03-03)](release-notes/rl-2.27.md)

diff --git a/doc/manual/source/advanced-topics/eval-profiler.md b/doc/manual/source/advanced-topics/eval-profiler.md
@@ -0,0 +1,33 @@
+# Using the `eval-profiler`
+
+Nix evaluator supports [evaluation](@docroot@/language/evaluation.md)
+[profiling](<https://en.wikipedia.org/wiki/Profiling_(computer_programming)>)
+compatible with `flamegraph.pl`. The profiler samples the nix
+function call stack at regular intervals. It can be enabled with the
+[`eval-profiler`](@docroot@/command-ref/conf-file.md#conf-eval-profiler)
+setting:
+
+```console
+$ nix-instantiate "<nixpkgs>" -A hello --eval-profiler flamegraph
+```
+
+Stack sampling frequency and the output file path can be configured with
+[`eval-profile-file`](@docroot@/command-ref/conf-file.md#conf-eval-profile-file)
+and [`eval-profiler-frequency`](@docroot@/command-ref/conf-file.md#conf-eval-profiler-frequency).
+By default the collected profile is saved to `nix.profile` file in the current working directory.
+
+The collected profile can be directly consumed by `flamegraph.pl`:
+
+```console
+$ flamegraph.pl nix.profile > flamegraph.svg
+```
+
+The line information in the profile contains the location of the [call
+site](https://en.wikipedia.org/wiki/Call_site) position and the name of the
+function being called (when available). For example:
+
+```
+/nix/store/x9wnkly3k1gkq580m90jjn32q9f05q2v-source/pkgs/top-level/default.nix:167:5:primop import
+```
+
+Here `import` primop is called at `/nix/store/x9wnkly3k1gkq580m90jjn32q9f05q2v-source/pkgs/top-level/default.nix:167:5`.
diff --git a/doc/manual/source/command-ref/nix-channel.md b/doc/manual/source/command-ref/nix-channel.md
@@ -59,6 +59,11 @@ This command has the following operations:
   Download the Nix expressions of subscribed channels and create a new generation.
   Update all channels if none is specified, and only those included in *names* otherwise.
 
+  > **Note**
+  >
+  > Downloaded channel contents are cached.
+  > Use `--tarball-ttl` or the [`tarball-ttl` configuration option](@docroot@/command-ref/conf-file.md#conf-tarball-ttl) to change the validity period of cached downloads.
+
 - `--list-generations`
 
   Prints a list of all the current existing generations for the

diff --git a/doc/manual/source/glossary.md b/doc/manual/source/glossary.md
@@ -31,9 +31,22 @@
 
   The industry term for storage and retrieval systems using [content addressing](#gloss-content-address). A Nix store also has [input addressing](#gloss-input-addressed-store-object), and metadata.
 
+- [derivation]{#gloss-derivation}
+
+  A derivation can be thought of as a [pure function](https://en.wikipedia.org/wiki/Pure_function) that produces new [store objects][store object] from existing store objects.
+
+  Derivations are implemented as [operating system processes that run in a sandbox](@docroot@/store/building.md#builder-execution).
+  This sandbox by default only allows reading from store objects specified as inputs, and only allows writing to designated [outputs][output] to be [captured as store objects](@docroot@/store/building.md#processing-outputs).
+
+  A derivation is typically specified as a [derivation expression] in the [Nix language], and [instantiated][instantiate] to a [store derivation].
+  There are multiple ways of obtaining store objects from store derivatons, collectively called [realisation][realise].
+
+  [derivation]: #gloss-derivation
+
 - [store derivation]{#gloss-store-derivation}
 
-  A single build task.
+  A [derivation] represented as a [store object].
+
   See [Store Derivation](@docroot@/store/derivation/index.md#store-derivation) for details.
 
   [store derivation]: #gloss-store-derivation
@@ -57,10 +70,7 @@
 
 - [derivation expression]{#gloss-derivation-expression}
 
-  A description of a [store derivation] in the Nix language.
-  The output(s) of a derivation are store objects.
-  Derivations are typically specified in Nix expressions using the [`derivation` primitive](./language/derivations.md).
-  These are translated into store layer *derivations* (implicitly by `nix-env` and `nix-build`, or explicitly by `nix-instantiate`).
+  A description of a [store derivation] using the [`derivation` primitive](./language/derivations.md) in the [Nix language].
 
   [derivation expression]: #gloss-derivation-expression
 

diff --git a/doc/manual/source/language/advanced-attributes.md b/doc/manual/source/language/advanced-attributes.md
@@ -53,23 +53,13 @@ Derivations can declare some infrequently used optional attributes.
 
   - [`__structuredAttrs`]{#adv-attr-structuredAttrs}\
     If the special attribute `__structuredAttrs` is set to `true`, the other derivation
-    attributes are serialised into a file in JSON format. The environment variable
-    `NIX_ATTRS_JSON_FILE` points to the exact location of that file both in a build
-    and a [`nix-shell`](../command-ref/nix-shell.md). This obviates the need for
-    [`passAsFile`](#adv-attr-passAsFile) since JSON files have no size restrictions,
-    unlike process environments.
-
-    It also makes it possible to tweak derivation settings in a structured way; see
-    [`outputChecks`](#adv-attr-outputChecks) for example.
-
-    As a convenience to Bash builders,
-    Nix writes a script that initialises shell variables
-    corresponding to all attributes that are representable in Bash. The
-    environment variable `NIX_ATTRS_SH_FILE` points to the exact
-    location of the script, both in a build and a
-    [`nix-shell`](../command-ref/nix-shell.md). This includes non-nested
-    (associative) arrays. For example, the attribute `hardening.format = true`
-    ends up as the Bash associative array element `${hardening[format]}`.
+    attributes are serialised into a file in JSON format.
+
+    This obviates the need for [`passAsFile`](#adv-attr-passAsFile) since JSON files have no size restrictions, unlike process environments.
+    It also makes it possible to tweak derivation settings in a structured way;
+    see [`outputChecks`](#adv-attr-outputChecks) for example.
+
+    See the [corresponding section in the derivation page](@docroot@/store/derivation/index.md#structured-attrs) for further details.
 
     > **Warning**
     >

diff --git a/doc/manual/source/language/index.md b/doc/manual/source/language/index.md
@@ -1,6 +1,6 @@
 # Nix Language
 
-The Nix language is designed for conveniently creating and composing *derivations* – precise descriptions of how contents of existing files are used to derive new files.
+The Nix language is designed for conveniently creating and composing [derivations](@docroot@/glossary.md#gloss-derivation) – precise descriptions of how contents of existing files are used to derive new files.
 
 > **Tip**
 >

diff --git a/doc/manual/source/language/operators.md b/doc/manual/source/language/operators.md
@@ -196,7 +196,7 @@ All comparison operators are implemented in terms of `<`, and the following equi
 
 ## Logical implication
 
-Equivalent to `!`*b1* `||` *b2*.
+Equivalent to `!`*b1* `||` *b2*  (or `if` *b1* `then` *b2* `else true`)
 
 [Logical implication]: #logical-implication
 

diff --git a/doc/manual/source/language/syntax.md b/doc/manual/source/language/syntax.md
@@ -225,8 +225,8 @@ passed in first , e.g.,
 
 ```nix
 let add = { __functor = self: x: x + self.x; };
-    inc = add // { x = 1; };
-in inc 1
+    inc = add // { x = 1; }; # inc is { x = 1; __functor = (...) }
+in inc 1 # equivalent of `add.__functor add 1` i.e. `1 + self.x`
 ```
 
 evaluates to `2`. This can be used to attach metadata to a function

diff --git a/doc/manual/source/protocols/json/derivation.md b/doc/manual/source/protocols/json/derivation.md
@@ -85,3 +85,7 @@ is a JSON object with the following fields:
 
 * `env`:
   The environment passed to the `builder`.
+
+* `structuredAttrs`:
+  [Strucutured Attributes](@docroot@/store/derivation/index.md#structured-attrs), only defined if the derivation contains them.
+  Structured attributes are JSON, and thus embedded as-is.
diff --git a/doc/manual/source/release-notes/rl-2.24.md b/doc/manual/source/release-notes/rl-2.24.md
@@ -284,7 +284,7 @@
 
   `<nix/fetchurl.nix>` is also known as the builtin derivation builder `builtin:fetchurl`. It's not to be confused with the evaluation-time function `builtins.fetchurl`, which was not affected by this issue.
 
-# Contributors
+## Contributors
 
 This release was made possible by the following 43 contributors:
 

diff --git a/doc/manual/source/release-notes/rl-2.25.md b/doc/manual/source/release-notes/rl-2.25.md
@@ -77,7 +77,7 @@
   `<nix/fetchurl.nix>` is also known as the builtin derivation builder `builtin:fetchurl`. It's not to be confused with the evaluation-time function `builtins.fetchurl`, which was not affected by this issue.
 
 
-# Contributors
+## Contributors
 
 This release was made possible by the following 58 contributors:
 

diff --git a/doc/manual/source/release-notes/rl-2.26.md b/doc/manual/source/release-notes/rl-2.26.md
@@ -76,7 +76,7 @@
 
 - Evaluation caching now works for dirty Git workdirs [#11992](https://github.com/NixOS/nix/pull/11992)
 
-# Contributors
+## Contributors
 
 This release was made possible by the following 45 contributors:
 

diff --git a/doc/manual/source/release-notes/rl-2.27.md b/doc/manual/source/release-notes/rl-2.27.md
@@ -47,7 +47,7 @@
   blake3-34P4p+iZXcbbyB1i4uoF7eWCGcZHjmaRn6Y7QdynLwU=
   ```
 
-# Contributors
+## Contributors
 
 This release was made possible by the following 21 contributors:
 

diff --git a/doc/manual/source/release-notes/rl-2.28.md b/doc/manual/source/release-notes/rl-2.28.md
@@ -82,7 +82,7 @@ This completes the infrastructure overhaul for the [RFC 132](https://github.com/
   Although this change is not as critical, we figured it would be good to do this API change at the same time, also.
   Also note that we try to keep the C API compatible, but we decided to break this function because it was young and likely not in widespread use yet. This frees up time to make important progress on the rest of the C API.
 
-# Contributors
+## Contributors
 
 This earlier-than-usual release was made possible by the following 16 contributors:
 

diff --git a/doc/manual/source/release-notes/rl-2.29.md b/doc/manual/source/release-notes/rl-2.29.md
@@ -111,7 +111,7 @@ This fact is counterbalanced by the fact that most of those changes are bug fixe
   This in particular prevents parts of GCC 14's diagnostics from being improperly filtered away.
 
 
-# Contributors
+## Contributors
 
 
 This release was made possible by the following 40 contributors: