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- Typescript - There is already an existing java wrapper for typescript compilation (typescript4j). I've played around with it in the demo project and managed to get it to compile a ts file, although compilation was painfully slow. The typescript4j project uses rhino to execute typescript compilation, which is known to be slow. However, JDK8 includes a brand new javascript engine called nashorn which is a complete rewrite, and it appears that the Oracle guys are using the typescript compiler as a benchmark to improve its performance. According to this very recent article, they made considerable progress in achieving near native performance. Furthermore, they are going to open source nashorn typescript for everyone to use.
- SCSS - there is an existing wrapper of the SCSS sass compiler that uses JRuby and includes all the Gems necessary to run it. I haven't tested it's performance, but from looking around, JRuby performance is generally considered similar to using native ruby.
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