packages `sqlite` and `libX11`:

```console
$ nix-shell --expr 'with import <nixpkgs> { }; runCommand "dummy" { buildInputs = [ sqlite xorg.libX11 ]; } ""'
```

A shorter way to do the same is:

```console
$ nix-shell --packages sqlite xorg.libX11
[nix-shell]$ echo $NIX_LDFLAGS
… -L/nix/store/j1zg5v…-sqlite-3.8.0.2/lib -L/nix/store/0gmcz9…-libX11-1.6.1/lib …
```

Note that `-p` accepts multiple full nix expressions that are valid in
the `buildInputs = [ ... ]` shown above, not only package names. So the
following is also legal:

```console
$ nix-shell --packages sqlite 'git.override { withManual = false; }'
```

The `-p` flag looks up Nixpkgs in the Nix search path. You can override
it by passing `-I` or setting `NIX_PATH`. For example, the following
gives you a shell containing the Pan package from a specific revision of
Nixpkgs:

```console
$ nix-shell --packages pan -I nixpkgs=https://github.com/NixOS/nixpkgs/archive/8a3eea054838b55aca962c3fbde9c83c102b8bf2.tar.gz

[nix-shell:~]$ pan --version
Pan 0.139
```

# Use as a `#!`-interpreter

You can use `nix-shell` as a script interpreter to allow scripts written
in arbitrary languages to obtain their own dependencies via Nix. This is
done by starting the script with the following lines:

```bash
#! /usr/bin/env nix-shell
#! nix-shell -i real-interpreter --packages packages
```

where *real-interpreter* is the “real” script interpreter that will be
invoked by `nix-shell` after it has obtained the dependencies and
initialised the environment, and *packages* are the attribute names of
the dependencies in Nixpkgs.

The lines starting with `#! nix-shell` specify `nix-shell` options (see
above). Note that you cannot write `#! /usr/bin/env nix-shell -i ...`
because many operating systems only allow one argument in `#!` lines.

For example, here is a Python script that depends on Python and the
`prettytable` package:

```python
#! /usr/bin/env nix-shell
#! nix-shell -i python3 --packages python3 python3Packages.prettytable

import prettytable

# Print a simple table.
t = prettytable.PrettyTable(["N", "N^2"])
for n in range(1, 10): t.add_row([n, n * n])
print(t)
```

Similarly, the following is a Perl script that specifies that it
requires Perl and the `HTML::TokeParser::Simple`, `LWP` and
`LWP::Protocol::Https` packages:

```perl
#! /usr/bin/env nix-shell
#! nix-shell -i perl 
#! nix-shell --packages perl 
#! nix-shell --packages perlPackages.HTMLTokeParserSimple 
#! nix-shell --packages perlPackages.LWP
#! nix-shell --packages perlPackages.LWPProtocolHttps