there is a mention of open-source SDK on this page: viewtopic.php?f=50&t=87
ESP8266 software is open source now, you can get it in the Downloads forum here.
However, I haven't found any source code in the latest SDK downloaded from the page mentioned above — there are only binaries for static linking. Am I missing something? Was the source available before? Are there any plans to release the source later?
Thank you,
Vlad