I think it's safe to say that the protocol is now in feature freeze for
version v1.0 and we are limiting changes to bug fixes and clarifications.
In order to locate things that we might have interpreted differently and
show how far we are when it comes to interoperability I've been testing the
three implementations that are most active in the spec against each other.
The result is the lightning integration test suite . It is still under
construction but has already found a few bugs/inconsistencies among
implementations. I also took the liberty of publishing some of the test
runs (annotated with enough metadata to reproduce them)  and will soon
add a nicer log view so that the cause of eventual failures is easier to
spot, and add some more tests for various scenarios.
I hope that this is a useful tool to check compatibility between
implementations, and I welcome any feedback or suggestions :-)
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