1. ArsonEfficient encoder and decoder for arbitrary objects
2. OptimismComposable reactive caching with efficient invalidation.
3. Immutable TupleImmutable finite list objects with constant-time equality testing (===) and no memory leaks.
4. Ast TypesEsprima-compatible implementation of the Mozilla JS Parser API
5. ReifyEnable ECMAScript 2015 modules in Node today. No caveats. Full stop.
6. RecastJavaScript syntax tree transformer, nondestructive pretty-printer, and automatic source map generator
8. privateUtility for associating truly private state with any JavaScript object
9. jsnext-skeletonSkeleton project demonstrating best practices for authoring and publishing the latest version of JavaScript to NPM.
10. es7-async-awaitTransformer that converts async functions and await expressions into ECMAScript 6 generator functions and yield expressions
12. wrywareA collection of packages that are probably a little too clever. Use at your own wrisk.