Moonlight, an implementation of Microsoft's Silverlight rich Internet plug-in platform for non-Windows systems, is no more, the lead developer of the project said this week.

In an interview posted on InfoQ, developer Miguel de Icaza, CTO at Xamarin, acknowledged abandoning Moonlight, which had been a Novell project prior to Xamarin's formation in 2011. "Silverlight has not gained much adoption on the Web, so it did not become the must-have technology that I thought [it] would have to become," de Icaza said. "And Microsoft added artificial restrictions to Silverlight that made it useless for desktop programming."

Moonlight developers no longer believe Silverlight is a suitable platform for write-once, run-anywhere technology because it has too many limitations, de Icaza said. Rather, he said that in the C# realm, the best option is to split code along the lines of the presentation layer. Users would reuse a core part of their application across all platforms and write a new UI specifically for each platform targeted, said de Icaza, noting that applications are not write-once, run-everywhere, but can exploit native facilities.

De Icaza, who also has been the key proponent of the open source Mono runtime, a version of .Net for non-Windows systems, could not be reached for comment on Tuesday afternoon.

Moonlight 1 was first released in the late-2008 timeframe. Xamarin's abandonment comes at a time when questions remain about Microsoft's commitment to Silverlight. Version 5 shipped this past December, but it is uncertain where Microsoft is going with the technology, if anywhere. Proprietary plug-ins like Silverlight and Adobe Flash have been under siege by the standards-based HTML5, which many see as the future of multimedia for Web applications.