I just published a new bit of open source code, a small Rack microservice for generating branded QR codes with a logo. For example, this page can be found with this QR-code:
It's simple to use, and to configure, at least for a Ruby programmer - just set up the base URL and the logo, and then call the service with whatever you want appended to the base URL. It returns a PNG image, cached with Redis for speed. Clear instructions are available on the repository.
... or you can deploy directly to Heroku with one click. Just click this button, pick out a server name, fill in your own values for
SIZE, and you'll be up and running in seconds!