This is a good initiate!
But:
1. Isn't the problem not so much that there isn't an open source bit software, but rather instagram shutting down API access?
How are we going to solve the API access problem? Having thousands of folks submitting the same OSS app to get API approval is not gonna work, I fear. Or are we okay with just using the API in sandbox mode, is that enough rate limits? Or is this software not gonna use the API at all?
2. Golang? Really? I know it's a new code-de-jour but if we're looking for codes/contributors we shouldn't limit ourselves, python/php/JavaScript should be enough imo. It's not like we need to worry about scaling and concurrency for a self hosted app, better to focus on fast code iteration etc.
Anyways, nice idea gl