diff --git a/README.md b/README.md
index e74d51a..2384c00 100644
--- a/README.md
+++ b/README.md
@@ -8,3 +8,16 @@ and capabilities, and capnproto-java is a pure Java implementation.
 [Read more here.](https://dwrensha.github.io/capnproto-java/index.html)
 
 This repository clone adds an implementation of the RPC framework for Java.
+
+Promise pipelining is provided via java.util.concurrent.CompletableFuture. Unlike the KJ asynchronous model, which completes promises
+only when they are waited upon, a CompletableFuture can complete immediately. This may break E-ordering, as the C++ implementation
+relies on kj::evalLater() to defer method calls, and there is no obvious (to me, anyway) way to replicate the behaviour of
+kj::evalLater() with CompletableFutures.
+
+Most of the C++ RPC test cases have been ported to this implementation, which gives me some comfort that the implementation logic is 
+correct, but more extensive testing is required. 
+
+This implementation does not support generic interfaces. Extending the schema compiler to output code for generic interfaces is an
+exercise I leave to the reader.
+
+