## User's guide (experimental new interface) {#sec-language-texlive-user-guide-experimental}
Release 23.11 ships with a new interface that will eventually replace `texlive.combine`.
- For basic usage, use some of the prebuilt environments available at the top level, such as `texliveBasic`, `texliveSmall`. For the full list of prebuilt environments, inspect `texlive.schemes`.
- Packages cannot be used directly but must be assembled in an environment. To create or add packages to an environment, use
```nix
texliveSmall.withPackages (ps: with ps; [ collection-langkorean algorithms cm-super ])
```
The function `withPackages` can be called multiple times to add more packages.
- **Note.** Within Nixpkgs, packages should only use prebuilt environments as inputs, such as `texliveSmall` or `texliveInfraOnly`, and should not depend directly on `texlive`. Further dependencies should be added by calling `withPackages`. This is to ensure that there is a consistent and simple way to override the inputs.
-`texlive.withPackages` uses the same logic as `buildEnv`. Only parts of a package are installed in an environment: its 'runtime' files (`tex` output), binaries (`out` output), and support files (`tlpkg` output). Moreover, man and info pages are assembled into separate `man` and `info` outputs. To add only the TeX files of a package, or its documentation (`texdoc` output), just specify the outputs:
```nix
texlive.withPackages (ps: with ps; [
texdoc # recommended package to navigate the documentation
perlPackages.LaTeXML.tex # tex files of LaTeXML, omit binaries
cm-super
cm-super.texdoc # documentation of cm-super
])
```
- All packages distributed by TeX Live, which contains most of CTAN, are available and can be found under `texlive.pkgs`:
```ShellSession
$ nix repl
nix-repl> :l <nixpkgs>
nix-repl> texlive.pkgs.[TAB]
```
Note that the packages in `texlive.pkgs` are only provided for search purposes and must not be used directly.
- **Experimental and subject to change without notice:** to add the documentation for all packages in the environment, use
- It typically won't work to use separately installed packages together. Instead, you can build a custom set of packages like this. Most CTAN packages should be available:
- By default you only get executables and files needed during runtime, and a little documentation for the core packages. To change that, you need to add `pkgFilter` function to `combine`.
- Note that the wrapper assumes that the result has a chance to be useful. For example, the core executables should be present, as well as some core data files. The supported way of ensuring this is by including some scheme, for example `scheme-basic`, into the combination.
- TeX Live packages are also available under `texlive.pkgs` as derivations with outputs `out`, `tex`, `texdoc`, `texsource`, `tlpkg`, `man`, `info`. They cannot be installed outside of `texlive.combine` but are available for other uses. To repackage a font, for instance, use
You may find that you need to use an external TeX package. A derivation for such package has to provide the contents of the "texmf" directory in its output and provide the appropriate `tlType` attribute (one of `"run"`, `"bin"`, `"doc"`, `"source"`). Dependencies on other TeX packages can be listed in the attribute `tlDeps`.
Such derivation must then be listed in the attribute `pkgs` of an attribute set passed to `texlive.combine`, for instance by passing `extraPkgs = { pkgs = [ custom_package ]; };`. Within Nixpkgs, `pkgs` should be part of the derivation itself, allowing users to call `texlive.combine { inherit (texlive) scheme-small; inherit some_tex_package; }`.
Here is a (very verbose) example where the attribute `pkgs` is attached to the derivation itself, which requires creating a fixed point. See also the packages `auctex`, `eukleides`, `mftrace` for more examples.
