The London Perl and Raku Workshop takes place on 26th Oct 2024. If your company depends on Perl, please consider sponsoring and/or attending.


Dancer::Plugin::NYTProf - easy Devel::NYTProf profiling for Dancer apps


    package MyApp;
    use Dancer ':syntax';

    # enables profiling and "/nytprof"
    use Dancer::Plugin::NYTProf;

Or, if you want to enable it only under development environment (as you should!), you can do something like:

    package MyApp;
    use Dancer ':syntax';

    # enables profiling and "/nytprof"
    if (setting('environment') eq 'development') {
        eval 'use Dancer::Plugin::NYTProf';


A plugin to provide easy profiling for Dancer applications, using the venerable Devel::NYTProf.

By simply loading this plugin, you'll have the detailed, helpful profiling provided by Devel::NYTProf.

Each individual request to your app is profiled. Going to the URL /nytprof in your app will present a list of profiles; selecting one will invoke nytprofhtml to generate the HTML reports (unless they already exist), then serve them up.

WARNING This is an early version of this code which is still in development. In general this isn't a plugin I'd advise to use in a production environment anyway, but in particular, it uses system to execute nytprofhtml, and I need to very carefully re-examine the code to make sure that user input cannot be used to nefarious effect. You are recommended to only use this in your development environment.


The plugin will work by default without any configuration required - it will default to writing profiling data into a dir named profdir within your Dancer application's appdir, present profiling output at /nytprof (not yet configurable), and profile all requests.

Below is an example of the options you can configure:

            enabled: 1
            profiling_enabled: 1
            profdir: '/tmp/profiledata'
            nytprofhtml_path: '/usr/local/bin/nytprofhtml'
            show_durations: 1


Where to store profiling data. Defaults to: $appdir/nytprof


Path to the nytprofhtml script that comes with Devel::NYTProf. Defaults to the first one we can find in your PATH environment. You should only need to change this in very specific environments, where nytprofhtml can't be found by this plugin.


Whether the plugin as a whole is enabled; disabling this setting will disable profiling route executions, and also disable the route which serves up the results at /nytprof. Enabled by default, so you only have to provide this setting if you wish to set it to a false value.


Whether route executions are profiled or not; if this is set to a false value, the before hook which would usually cause Devel::NYTProf to profile that route execution will not do so. This allows you to disable profiling but still be able to browse the results of existing profiled executions. Enabled by default, so you only have to provide this setting if you wish to set it to a false value.


When listing profile runs, show the duration of each run, extracted from the profiling data. If you have a lot of profiled runs, this might get slow, so this option is provided if you don't need the profile durations displayed when listing profiles, preferring a faster list. Defaults to 1.

More configuration (such as the URL at which output is produced, and options to control which requests get profiled) will be added in a future version. (If there's something you'd like to see soon, do contact me and let me know - it'll likely get done a lot quicker then!)


David Precious, <davidp at>


Stefan Hornburg (racke)

Neil Hooey (nhooey)

J. Bobby Lopez (jbobbylopez)


Breno G. de Oliveira (garu)


Please report any bugs or feature requests at


This module is developed on GitHub:

Bug reports, suggestions and pull requests all welcomed!






Copyright 2011-2014 David Precious.

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See for more information.