You're supposed to use setImmediate in node >=0.10 instead of process.nextTick. The test cases were only passing because none of them tested on more documents than process.maxTickDepth (by default 1000). If you run on more documents than that, it crashes with RangeError: maximum call stack size exceeded.
RangeError: maximum call stack size exceeded
I artificially lowered process.maxTickDepth in one of the test cases to generate a failing test case, then changed all instances of process.nextTick to use setImmediate where available and verified that the test cases are passing again.
I didn't submit any of the compiled js because my version of coffee-script is different than your's so there were a lot of diffs that were just white noise.
setImmediate instead of nextTick for node >=0.10
Excellent catch and thanks for the clean commit
Generate js code from issue #122
A new version is published with your changes