Hello there,
I am the main developer of the new Microdevt development toolkit basically made for micro controllers www.kw-net.com
If you are an AVR enthusiast and are tired of the high lever Arduino IDE, you can check out this powerful low-level toolkit and start developing quickly your applications.
The toolkit features timers, task schedulers, a zero-copy, event-based TCP/IP stack and many other tools. A documentation is available as well as a few example projects (see projects page).
The source code can be found here: https://www.kw-net.com/en/download/
Feel free to report any bugs here: https://www.kw-net.com/en/contact/
The whole project is open sourced (GPL licensed).