Point contributors to the hacking docs in README.md.
Fixes
@@ -57,7 +57,8 @@ guide.
# Contributing
We welcome contributions in all forms. Please check out
-the [contributing guide](CONTRIBUTING.md) for more information.
+the [contributing guide](CONTRIBUTING.md) for more information, and
+the [hacking guide](docs/hacking.md) for some technical pointers.
One lightweight way you can contribute is
to
