# Fixing an 'unknown source' issue preventing Eclipse debugging within a custom Processing library

**URL:** <https://discourse.processing.org/t/fixing-an-unknown-source-issue-preventing-eclipse-debugging-within-a-custom-processing-library/23432>\
**Category:** Development\
**Created:** [August 23, 2020, 3:03am UTC](https://discourse.processing.org/t/fixing-an-unknown-source-issue-preventing-eclipse-debugging-within-a-custom-processing-library/23432 "2020-08-23T03:03:04Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![colinpt](https://avatars.discourse-cdn.com/v4/letter/c/59ef9b/32.png) [@colinpt](https://discourse.processing.org/u/colinpt)\
**Post date:** [August 23, 2020, 3:03am UTC](https://discourse.processing.org/t/fixing-an-unknown-source-issue-preventing-eclipse-debugging-within-a-custom-processing-library/23432/1 "2020-08-23T03:03:04Z")

</div>

I’m building myself a processing library, and I would like to be able to step into my library methods fro my Proclipsing sketch in order to properly debug. However, after trying numerous fixes, I am unable to get this functionality.

I am using [the Processing library template](https://github.com/processing/processing-library-template), and its built-in .xml + ant to compile my .jar

Everything runs well, but if I attempt to step into a library method I end up on [this screen.](http://blob:https://imgur.com/1a4d0b2a-a53d-4df0-8efc-04b584a8889e) I have tried attaching the source, but that does not seem to change anything.

I have also tried [all the suggestions on this page](https://forum.processing.org/two/discussion/6258/how-to-attach-a-debugger-to-my-library) to no avail.

EDIT:  
[This is how my source is attached to the .jar](https://i.imgur.com/c7qyyWq.png)