via Kirill Sheynkman:
Open source popularized the idea of creating public projects and actively soliciting community feedback and involvement. Tens of thousands of open source projects have been created, but only those projects that built sizable communities have thrived. Most of the large infrastructure software categories were eventually filled by strong open source projects and some spawned successful commercial software companies, like RedHat, XenSource, Sourcefire, MySQL, and JBoss. These companies span a broad range — from operating systems/hypervisors to security to middleware and database/content management.
Coders now expect the same instant gratification as end users. Instead of having to download, configure and manage all the associated software components, more and more of these capabilities need to be packaged “as-a-service” — hence, the move to cloud services. It is also important to remember that software development is an art, not a science, and programmers want a very simple and elegant programming interface.
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