Hi Barry, We continue to work on this issue, but have not yet succeeded in getting installation as a source dependency to work. We hope to get it resolved soon, but it's hard to say exactly how long it will take, so in the interest of allowing you to make progress I suggest using an alternate approach -- include mdtraj as an additional package in your bundle. In your bundle_info.xml you would use an AdditionalPackages tag with a child tag of "Package" which has a "name" attribute of "mdtraj" and a "folder" attribute of wherever mdtraj got installed. Since mdtraj is not pure Python, you would also have to use a "platform" attribute of mac/linux/windows. If you also built mdtraj on other platforms you could copy it over to the machine you're building the bundle on and include additional Package tags with different platform/folder values. You also have to have a DataFiles tag with a "package" attribute of "mdtraj" and an appropriate "platform" attribute, with child DataDir/DataFile tags enumerating what to copy from the installation. One thing to keep in mind is that the installation has to be compatible with the version of Python ChimeraX is using, which is Python 3.9 for ChimeraX 1.6.1 and Python 3.11 for the daily build. So you would want to include the corresponding dependency on ChimeraX-Core. Also, a binary version of mdtraj is available for Mac (Python 3.9) so you could conceivably include that directly as a dependency (i.e. in a Dependency tag rather than a Package tag) with a "mac" platform attribute and a ChimeraX-Core dependency of ==1.6.1. For reference, SEQCROW uses the AdditionalPackages tag in its bundle_info.xml, which you can see here. <https://github.com/QChASM/SEQCROW/blob/master/bundle_info.xml> --Eric Eric Pettersen UCSF Computer Graphics Lab

OK. So, we decided to wipe some computers and start fresh to install our plugin. And using the daily build from a couple days ago and a daily build from 7-15 and always on a freshly built linux 20.04 system we are unable to install my plugin. However, it somehow installed in the past on my coworker's system (using 7-15 chimerax) and my system (using 6-6 chimerax). He and I can both repeatedly install and uninstall my plugin. But any clean system will not "devel install" the plugin. Below is the latest log output using the daily build from 7-15 (because we have one user successfully using it). I am at a real loss as to what is going on. FWIW the clean systems do also have python 2.7. I know recently you fixed a problem of installing a plugin on a system that has python 2.7 on it. Please let me know what I can do. Our plugin is alpha ready and if I can't get it easily installable then our project is at a standstill.