Last covered at the end of 2017, WP Internals is a tool that lets you flash images 'to order' to your Lumia phone - and is strictly for those who know exactly what they're doing (it's beyond me!) Anyway, it just went Open Source. Which either means that it'll never be updated again, or that some keen souls can take the tool forward to greater heights. Who knows?

The developer has now posted:

I uploaded all the source-code of Windows Phone Internals to Github. I also created some tooling which helped me developing Windows Phone Internals. I will upload this to Github too somewhere soon. I will still do some development, but don't have much time for it lately. So I hope other developers and hackers can contribute too. If Microsoft will ever release a Surface phone, I will have a new challenge and work on that. Maybe I will try to hack an iPhone in the meantime, LOL. The source of Windows Phone Internals can be found here: https://github.com/ReneLergner/WPinternals

Happy coding!
René

Back when this project started, there was hope of Lumias being unlocked and then flashed beyond the current 'feature2_rs3' OS branches. Which should, in theory, be possible, because of the shared Windows 10 code with the Desktop. But we haven't currently seen any builds which are usable in a mainstream context.

Still, who knows? If you're a good coder and looking for a rainy day project then why not get involved?