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diff --git a/src/nix/nix.md b/src/nix/nix.md
index 14407428e..5da146fc6 100644
--- a/src/nix/nix.md
+++ b/src/nix/nix.md
@@ -48,22 +48,26 @@ manual](https://nixos.org/manual/nix/stable/).
# Installables
-Many `nix` subcommands operate on one or more *installables*. These are
-command line arguments that represent something that can be built in
-the Nix store.
+Many `nix` subcommands operate on one or more *installables*.
+These are command line arguments that represent something that can be realised in the Nix store.
-For most commands, if no installable is specified, the default is `.`,
-i.e. Nix will operate on the default flake output attribute of the
-flake in the current directory.
+The following types of installable are supported by most commands:
-Here are the recognised types of installables:
+- [Flake output attribute](#flake-output-attribute)
+- [Store path](#store-path)
+- [Store derivation](#store-derivation)
+- [Nix file](#nix-file), optionally qualified by an attribute path
+- [Nix expression](#nix-expression), optionally qualified by an attribute path
-## Flake output attributes
+For most commands, if no installable is specified, `.` as assumed.
+That is, Nix will operate on the default flake output attribute of the flake in the current directory.
+
+### Flake output attribute
Example: `nixpkgs#hello`
These have the form *flakeref*[`#`*attrpath*], where *flakeref* is a
-flake reference and *attrpath* is an optional attribute path. For
+[flake reference](./nix3-flake.md#flake-references) and *attrpath* is an optional attribute path. For
more information on flakes, see [the `nix flake` manual
page](./nix3-flake.md). Flake references are most commonly a flake
identifier in the flake registry (e.g. `nixpkgs`), or a raw path
@@ -116,46 +120,46 @@ subcommands, these are `packages.`*system*,
attributes `packages.x86_64-linux.hello`,
`legacyPackages.x86_64-linux.hello` and `hello`.
-## Store paths
+### Store path
Example: `/nix/store/v5sv61sszx301i0x6xysaqzla09nksnd-hello-2.10`
-These are paths inside the Nix store, or symlinks that resolve to a
-path in the Nix store.
+These are paths inside the Nix store, or symlinks that resolve to a path in the Nix store.
-## Store derivations
+### Store derivation
Example: `/nix/store/p7gp6lxdg32h4ka1q398wd9r2zkbbz2v-hello-2.10.drv`
-By default, if you pass a [store derivation] path to a `nix` subcommand, the command will operate on the [output path]s of the derivation.
+By default, if you pass a [store derivation] path to a `nix` subcommand other than [`show-derivation`](./nix3-show-derivation.md), the command will operate on the [output path]s of the derivation.
[output path]: ../../glossary.md#gloss-output-path
-For example, `nix path-info` prints information about the output paths:
+For example, [`nix path-info`](./nix3-path-info.md) prints information about the output paths:
```console
# nix path-info --json /nix/store/p7gp6lxdg32h4ka1q398wd9r2zkbbz2v-hello-2.10.drv
[{"path":"/nix/store/v5sv61sszx301i0x6xysaqzla09nksnd-hello-2.10",…}]
```
-If you want to operate on the store derivation itself, pass the
-`--derivation` flag.
+If you want to operate on the store derivation itself, pass the `--derivation` flag.
-## Nix attributes
+### Nix file
Example: `--file /path/to/nixpkgs hello`
-When the `-f` / `--file` *path* option is given, installables are
-interpreted as attribute paths referencing a value returned by
-evaluating the Nix file *path*.
+When the option `-f` / `--file` *path* \[*attrpath*...\] is given, installables are interpreted as the value of the expression in the Nix file at *path*.
+If attribute paths are provided, commands will operate on the corresponding values accessible at these paths.
+The Nix expression in that file, or any selected attribute, must evaluate to a derivation.
+
+### Nix expression
-## Nix expressions
+Example: `--expr 'import <nixpkgs> {}' hello`
-Example: `--expr '(import <nixpkgs> {}).hello.overrideDerivation (prev: { name = "my-hello"; })'`.
+When the option `--expr` *expression* \[*attrpath*...\] is given, installables are interpreted as the value of the of the Nix expression.
+If attribute paths are provided, commands will operate on the corresponding values accessible at these paths.
+The Nix expression, or any selected attribute, must evaluate to a derivation.
-When the `--expr` option is given, all installables are interpreted
-as Nix expressions. You may need to specify `--impure` if the
-expression references impure inputs (such as `<nixpkgs>`).
+You may need to specify `--impure` if the expression references impure inputs (such as `<nixpkgs>`).
## Derivation output selection