Hi Gabriel

Thanks for your post. If I'm understanding your use case correctly I think you might find our article on Creating Custom Shapes useful. I hope this helps! Please let me know if you have further questions. 

This is exactly what I needed. To help others with search term hits I'll mention that I searched: reuse instance and custom symbol.

UPDATE: It's not quite what I hoped for. What I wanted was something that would allow me to have live connections with the library by which I mean I can change a line style or color in the library and all instances will reflect the change. The current functionality as I understand it is no different than copying and pasting. All copies are independent.

I think Gabriel R and Andre V are talking about component concept from front-end-engineering.

Hey everyone 

Thank you all for the input and dedication to make Lucidchart as great as it can possibly be! We do have the ability to import shapes however they would be imported as an image and would not reflect any line/color fill changes that you would make. This does however seem like a great idea and we would love to hear more. Would you mind expressing your ideas here--this will allow our devs to take a look and see if it is something we can implement in the future. 

Again thank you all so much for sharing your ideas that will help your workflow! Firm handshakes all around