Yeah, if it builds in `src`, it should be removed from the repo and ignored. Ideally, it would build into a build directory -- because now you'll need to remove `src/natives.coffee` as part of `make clean`. I can see *why* you did this, though -- not doing this would break our development build, which expects to run `coffee` on `src/natives.coffee`.

It's not dramatic, I just don't see the advantage. We've added a dependency on a tool for concatenation, when we already concatenate in the Makefile. Our build process is already really crazy.

You could add the following to the `Makefile` for the same result (note: untested!):

```
# Get list of native sources in alphabetical order.
NATIVE_SRCS := $(wildcard src/natives/*.coffee)

src/natives.coffee: $(NATIVE_SRCS)
  for src in $(NATIVE_SRCS); do \
    cat $(src) \
  done > src/natives.coffee
```

Provided that the various `Makefile` targets (`release`, `dev`, etc) correctly depend on their source files, this should automagically trigger appropriately.