AWS IoT Integration: one for each application?

Short version: does each Application on TTN require a separate AWS Integration instance?

I have added another application to my (Community) console and I am receiving messages. I already have an existing application that connects to an AWS IoT integration and it is working perfectly. I need to add the new application to AWS IoT but I am not clear whether it is necessary to create an entirely new AWS integration instance for this new application, or if I can use the same CloudFormation stack and Role ARN with both applications simultaneously.

Since the integration is responsible for creating and deleting AWS IoT objects (for each end node on TTN) I thought there might be a conflict if two separate TTN Applications access the same AWS Integration instance. If, however, the AWS integration is “smart enough” to manage multiple TTN Applications then a second instance is not necessary.

It’s not completely clear, but it may not affect the cost since the AWS integration appears mostly to run in Lambda functions (on an as-needed basis), so creating another instance from the cloudformation template may not cost more than using the existing one.

Is the source code for the integration available on GitHub or elsewhere? I’m happy to dig through and find out the answer myself and post the results here. Either way I’ll post what I learn.

Anyone else out there using AWS that can comment on this? Sounds like the AWS integration isn’t getting a lot of use based on the lack of activity here on this question, but the integration otherwise seems to run well and appears to be quite stable and well written. Perhaps the integration just runs so well that nobody has any questions about it. =-)