A warning for those who build a livelihood on proprietary systems and services:
Cloud9 (cloud IDE, deployment, and hosting) was bought by Amazon a few years ago, and is now shutting down its original service this December, leaving users scrambling who don't want to migrate to AWS.
https://community.c9.io/t/is-cloud9-being-replaced-with-aws-cloud-9/20910
* One user has 147 Cloud9 projects that he doesn't know what to do with;
* Another spent countless hours building course-ware and video tutorials that are now completely useless.