···

       
29
       
 
       
    4.  If needed you can also run `make menuconfig`:

     

       
30
       
 
       


     

       
31
       
 
       
        ```ShellSession

     

       
32
       
-
       
        $ nix-env -i ncurses

     

       
33
       
 
       
        $ export NIX_CFLAGS_LINK=-lncurses

     

       
34
       
 
       
        $ make menuconfig ARCH=arch

     

       
35
       
 
       
        ```

     

···

       
29
       
 
       
    4.  If needed you can also run `make menuconfig`:

     

       
30
       
 
       


     

       
31
       
 
       
        ```ShellSession

     

       
32
       
+
       
        $ nix-env -f "<nixpkgs>" -iA ncurses

     

       
33
       
 
       
        $ export NIX_CFLAGS_LINK=-lncurses

     

       
34
       
 
       
        $ make menuconfig ARCH=arch

     

       
35
       
 
       
        ```

     

···

       
43
       
 
       
  - nixpkgs:

     

       
44
       
 
       


     

       
45
       
 
       
    - update pkg

     

       
46
       
-
       
      - `nix-env -i pkg-name -f <path to your local nixpkgs folder>`

     

       
47
       
 
       
    - add pkg

     

       
48
       
 
       
      - Make sure it’s in `pkgs/top-level/all-packages.nix`

     

       
49
       
-
       
      - `nix-env -i pkg-name -f <path to your local nixpkgs folder>`

     

       
50
       
 
       
    - _If you don’t want to install pkg in you profile_.

     

       
51
       
-
       
      - `nix-build -A pkg-attribute-name <path to your local nixpkgs folder>/default.nix` and check results in the folder `result`. It will appear in the same directory where you did `nix-build`.

     

       
52
       
-
       
    - If you did `nix-env -i pkg-name` you can do `nix-env -e pkg-name` to uninstall it from your system.

     

       
53
       
 
       


     

       
54
       
 
       
  - NixOS and its modules:

     

       
55
       
 
       
    - You can add new module to your NixOS configuration file (usually it’s `/etc/nixos/configuration.nix`). And do `sudo nixos-rebuild test -I nixpkgs=<path to your local nixpkgs folder> --fast`.

     

···

       
43
       
 
       
  - nixpkgs:

     

       
44
       
 
       


     

       
45
       
 
       
    - update pkg

     

       
46
       
+
       
      - `nix-env -iA pkg-attribute-name -f <path to your local nixpkgs folder>`

     

       
47
       
 
       
    - add pkg

     

       
48
       
 
       
      - Make sure it’s in `pkgs/top-level/all-packages.nix`

     

       
49
       
+
       
      - `nix-env -iA pkg-attribute-name -f <path to your local nixpkgs folder>`

     

       
50
       
 
       
    - _If you don’t want to install pkg in you profile_.

     

       
51
       
+
       
      - `nix-build -A pkg-attribute-name <path to your local nixpkgs folder>` and check results in the folder `result`. It will appear in the same directory where you did `nix-build`.

     

       
52
       
+
       
    - If you installed your package with `nix-env`, you can run `nix-env -e pkg-name` where `pkg-name` is as reported by `nix-env -q` to uninstall it from your system.

     

       
53
       
 
       


     

       
54
       
 
       
  - NixOS and its modules:

     

       
55
       
 
       
    - You can add new module to your NixOS configuration file (usually it’s `/etc/nixos/configuration.nix`). And do `sudo nixos-rebuild test -I nixpkgs=<path to your local nixpkgs folder> --fast`.

     

···

       
15
       
 
       


     

       
16
       
 
       
   If you want to work with `emcc`, `emconfigure` and `emmake` as you are used to from Ubuntu and similar distributions you can use these commands:

     

       
17
       
 
       


     

       
18
       
-
       
    * `nix-env -i emscripten`

     

       
19
       
 
       
    * `nix-shell -p emscripten`

     

       
20
       
 
       


     

       
21
       
 
       
* **Declarative usage**:

     

       
22
       
 
       


     

       
23
       
-
       
    This mode is far more power full since this makes use of `nix` for dependency management of emscripten libraries and targets by using the `mkDerivation` which is implemented by `pkgs.emscriptenStdenv` and `pkgs.buildEmscriptenPackage`. The source for the packages is in `pkgs/top-level/emscripten-packages.nix` and the abstraction behind it in `pkgs/development/em-modules/generic/default.nix`.

     

       
24
       
 
       
    * build and install all packages:

     

       
25
       
 
       
        * `nix-env -iA emscriptenPackages`

     

       
26
       
 
       


     

···

       
15
       
 
       


     

       
16
       
 
       
   If you want to work with `emcc`, `emconfigure` and `emmake` as you are used to from Ubuntu and similar distributions you can use these commands:

     

       
17
       
 
       


     

       
18
       
+
       
    * `nix-env -f "<nixpkgs>" -iA emscripten`

     

       
19
       
 
       
    * `nix-shell -p emscripten`

     

       
20
       
 
       


     

       
21
       
 
       
* **Declarative usage**:

     

       
22
       
 
       


     

       
23
       
+
       
    This mode is far more power full since this makes use of `nix` for dependency management of emscripten libraries and targets by using the `mkDerivation` which is implemented by `pkgs.emscriptenStdenv` and `pkgs.buildEmscriptenPackage`. The source for the packages is in `pkgs/top-level/emscripten-packages.nix` and the abstraction behind it in `pkgs/development/em-modules/generic/default.nix`. From the root of the nixpkgs repository:

     

       
24
       
 
       
    * build and install all packages:

     

       
25
       
 
       
        * `nix-env -iA emscriptenPackages`

     

       
26
       
 
       


     

···

       
5
       
 
       
The easiest way to get a working idris version is to install the `idris` attribute:

     

       
6
       
 
       


     

       
7
       
 
       
```ShellSession

     

       
8
       
-
       
$ # On NixOS

     

       
9
       
-
       
$ nix-env -i nixos.idris

     

       
10
       
-
       
$ # On non-NixOS

     

       
11
       
-
       
$ nix-env -i nixpkgs.idris

     

       
12
       
 
       
```

     

       
13
       
 
       


     

       
14
       
 
       
This however only provides the `prelude` and `base` libraries. To install idris with additional libraries, you can use the `idrisPackages.with-packages` function, e.g. in an overlay in `~/.config/nixpkgs/overlays/my-idris.nix`:

     

···

       
5
       
 
       
The easiest way to get a working idris version is to install the `idris` attribute:

     

       
6
       
 
       


     

       
7
       
 
       
```ShellSession

     

       
8
       
+
       
$ nix-env -f "<nixpkgs>" -iA idris

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
9
       
 
       
```

     

       
10
       
 
       


     

       
11
       
 
       
This however only provides the `prelude` and `base` libraries. To install idris with additional libraries, you can use the `idrisPackages.with-packages` function, e.g. in an overlay in `~/.config/nixpkgs/overlays/my-idris.nix`:

     

···

       
24
       
 
       
$ nix-build -A octavePackages.symbolic

     

       
25
       
 
       
```

     

       
26
       
 
       


     

       
27
       
-
       
When building Octave packages with `nix-build`, the `buildOctavePackage` function adds `octave-octaveVersion` to; the start of the package's name attribute.

     

       
28
       
-
       


     

       
29
       
-
       
This can be required when installing the package using `nix-env`:

     

       
30
       
-
       


     

       
31
       
-
       
```ShellSession

     

       
32
       
-
       
$ nix-env -i octave-6.2.0-symbolic

     

       
33
       
-
       
```

     

       
34
       
-
       


     

       
35
       
-
       
Although, you can also install it using the attribute name:

     

       
36
       
 
       


     

       
37
       
 
       
```ShellSession

     

       
38
       
-
       
$ nix-env -i -A octavePackages.symbolic

     

       
39
       
 
       
```

     

       
40
       
 
       


     

       
41
       
 
       
You can build Octave with packages by using the `withPackages` passed-through function.

     

···

       
24
       
 
       
$ nix-build -A octavePackages.symbolic

     

       
25
       
 
       
```

     

       
26
       
 
       


     

       
27
       
+
       
To install it into your user profile, run this command from the root of the repository:

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
28
       
 
       


     

       
29
       
 
       
```ShellSession

     

       
30
       
+
       
$ nix-env -f. -iA octavePackages.symbolic

     

       
31
       
 
       
```

     

       
32
       
 
       


     

       
33
       
 
       
You can build Octave with packages by using the `withPackages` passed-through function.

     

···

       
58
       
 
       
$ nix-build -A perlPackages.ClassC3

     

       
59
       
 
       
```

     

       
60
       
 
       


     

       
61
       
-
       
`buildPerlPackage` adds `perl-` to the start of the name attribute, so the package above is actually called `perl-Class-C3-0.21`. So to install it, you can say:

     

       
62
       
-
       


     

       
63
       
-
       
```ShellSession

     

       
64
       
-
       
$ nix-env -i perl-Class-C3

     

       
65
       
-
       
```

     

       
66
       
-
       


     

       
67
       
-
       
(Of course you can also install using the attribute name: `nix-env -i -A perlPackages.ClassC3`.)

     

       
68
       
 
       


     

       
69
       
 
       
So what does `buildPerlPackage` do? It does the following:

     

       
70
       
 
       


     
···

       
135
       
 
       
Nix expressions for Perl packages can be generated (almost) automatically from CPAN. This is done by the program `nix-generate-from-cpan`, which can be installed as follows:

     

       
136
       
 
       


     

       
137
       
 
       
```ShellSession

     

       
138
       
-
       
$ nix-env -i nix-generate-from-cpan

     

       
139
       
 
       
```

     

       
0
       
 
       

     

       
0
       
 
       

     

       
140
       
 
       


     

       
141
       
 
       
This program takes a Perl module name, looks it up on CPAN, fetches and unpacks the corresponding package, and prints a Nix expression on standard output. For example:

     

       
142
       
 
       


     

···

       
58
       
 
       
$ nix-build -A perlPackages.ClassC3

     

       
59
       
 
       
```

     

       
60
       
 
       


     

       
61
       
+
       
To install it with `nix-env` instead: `nix-env -f. -iA perlPackages.ClassC3`.

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
0
       
 
       

     

       
62
       
 
       


     

       
63
       
 
       
So what does `buildPerlPackage` do? It does the following:

     

       
64
       
 
       


     
···

       
129
       
 
       
Nix expressions for Perl packages can be generated (almost) automatically from CPAN. This is done by the program `nix-generate-from-cpan`, which can be installed as follows:

     

       
130
       
 
       


     

       
131
       
 
       
```ShellSession

     

       
132
       
+
       
$ nix-env -f "<nixpkgs>" -iA nix-generate-from-cpan

     

       
133
       
 
       
```

     

       
134
       
+
       


     

       
135
       
+
       
Substitute `<nixpkgs>` by the path of a nixpkgs clone to use the latest version.

     

       
136
       
 
       


     

       
137
       
 
       
This program takes a Perl module name, looks it up on CPAN, fetches and unpacks the corresponding package, and prints a Nix expression on standard output. For example:

     

       
138