$c->stash->{drvAvailable} = isValidPath $build->drvpath;

    error($c, "Product " . $product->path . " has disappeared.") unless -e $product->path;

    notFound($c, "Product " . $product->path . " has disappeared.") unless -e $product->path;

sub runtimedeps : Chained('build') PathPart('runtime-deps') {
    my ($self, $c) = @_;
    
    my $build = $c->stash->{build};
    
    notFound($c, "Path " . $build->outpath . " is no longer available.")
        unless isValidPath($build->outpath);
    
    $c->stash->{current_view} = 'Hydra::View::NixDepGraph';
    $c->stash->{storePaths} = [$build->outpath];
    
    $c->response->content_type('image/png'); # !!!
}
sub buildtimedeps : Chained('build') PathPart('buildtime-deps') {
    my ($self, $c) = @_;
    
    my $build = $c->stash->{build};
    
    notFound($c, "Path " . $build->drvpath . " is no longer available.")
        unless isValidPath($build->drvpath);
    
    $c->stash->{current_view} = 'Hydra::View::NixDepGraph';
    $c->stash->{storePaths} = [$build->drvpath];
    
    $c->response->content_type('image/png'); # !!!
}

package Hydra::View::NixDepGraph;
use strict;
use base qw/Catalyst::View/;
use IO::Pipe;
sub process {
    my ($self, $c) = @_;
    
    $c->response->content_type('image/png');
    my @storePaths = @{$c->stash->{storePaths}};
    open(OUTPUT, "nix-store --query --graph @storePaths | dot -Tpng -Gbgcolor=transparent |");
    my $fh = new IO::Handle;
    $fh->fdopen(fileno(OUTPUT), "r") or die;
    $c->response->body($fh);
    
    return 1;
}
1;

    <td><tt>[% build.drvpath %]</tt></td>

    <td>
      <tt>[% build.drvpath %]</tt>
      [% IF drvAvailable %]
        (<a href="[% c.uri_for('/build' build.id 'buildtime-deps') %]">build-time dependencies</a>)
      [% END %]
    </td>

    <td><tt>[% build.outpath %]</tt></td>

    <td>
      <tt>[% build.outpath %]</tt>
      [% IF available %]
        (<a href="[% c.uri_for('/build' build.id 'runtime-deps') %]">runtime dependencies</a>)
      [% END %]
    </td>