Move docker command and provision to its own folder.
Install mercurial for Go.
Prepare a go tester service.
Render windowless.
Close browser once the source code has been retrieved.
Answer with a response with the correct error code when the page doesn't load correctly.
Close the process correctly when there are no pending requests when the exit is requested (throw the close in the UI thread)
Return an error response in case of a name resolution error.
Don't fail when a frame is aborted (in a blacklisted iframe for example)
Let the handler instantiate its dependencies.
Organize code better to have each handler instance with its dependencies and initializers in the correct places.