diff --git a/test/Makefile b/test/Makefile
index 780993c..3a474cf 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -54,6 +54,10 @@ TESTPROD += testput
 testput_SRCS += testput.cpp
 TESTS += testput
 
+TESTPROD += testrpc
+testrpc_SRCS += testrpc.cpp
+TESTS += testrpc
+
 TESTPROD += dummyserv
 dummyserv_SRCS += dummyserv.cpp
 # not a unittest
diff --git a/test/testrpc.cpp b/test/testrpc.cpp
new file mode 100644
index 0000000..77a6568
--- /dev/null
+++ b/test/testrpc.cpp
@@ -0,0 +1,173 @@
+/**
+ * Copyright - See the COPYRIGHT that is included with this distribution.
+ * pvxs is distributed subject to a Software License Agreement found
+ * in file LICENSE that is included with this distribution.
+ */
+
+#include <atomic>
+
+#include <testMain.h>
+
+#include <epicsUnitTest.h>
+
+#include <epicsEvent.h>
+
+#include <pvxs/unittest.h>
+#include <pvxs/log.h>
+#include <pvxs/client.h>
+#include <pvxs/server.h>
+#include <pvxs/sharedpv.h>
+#include <pvxs/source.h>
+#include <pvxs/nt.h>
+
+namespace {
+using namespace pvxs;
+
+struct Tester {
+    client::Result actual;
+    epicsEvent done;
+    Value initial;
+    server::SharedPV mbox;
+    server::Server serv;
+    client::Context cli;
+    bool fail = false;
+
+    Tester()
+        :initial(nt::NTScalar{TypeCode::Int32}.create())
+        ,mbox(server::SharedPV::buildMailbox())
+        ,serv(server::Config::localhost()
+              .build()
+              .addPV("mailbox", mbox))
+        ,cli(serv.clientConfig().build())
+    {
+        testShow()<<"Server:\n"<<serv.config()
+                  <<"Client:\n"<<cli.config();
+
+        initial["value"] = 1;
+
+        mbox.onRPC([this](server::SharedPV& pv, std::unique_ptr<server::ExecOp>&& op, Value&& arg) {
+            if(fail)
+                op->error("oops");
+            else
+                op->reply(arg); // echo
+        });
+    }
+
+    std::shared_ptr<client::Operation> doCall(Value&& arg)
+    {
+
+        auto op = cli.rpc("mailbox", std::move(arg))
+                .result([this](client::Result&& result) {
+                    actual = std::move(result);
+                    done.trigger();
+                })
+                .exec();
+
+        cli.hurryUp();
+
+        return op;
+    }
+
+    Value testWaitOk()
+    {
+        if(testOk1(done.wait(5.0))) {
+            try {
+                auto ret = actual();
+                testPass("RPC success");
+                return ret;
+            }catch(std::exception& e){
+                testFail("RPC error %s : %s", typeid (e).name(), e.what());
+            }
+        } else {
+            testSkip(1, "timeout");
+        }
+        return Value();
+    }
+
+    void echo()
+    {
+        mbox.open(initial);
+        serv.start();
+
+        auto arg = initial.cloneEmpty();
+        arg["value"] = 42;
+        auto op = doCall(std::move(arg));
+        if(auto ret = testWaitOk()) {
+
+            int32_t v=0;
+            testOk1(!!ret["value"].as(v));
+            testEq(v, 42);
+        }
+    }
+
+    void lazy()
+    {
+        // mbox not open
+        serv.start();
+
+        auto arg = initial.cloneEmpty();
+        arg["value"] = 42;
+        auto op = doCall(std::move(arg));
+        if(auto ret = testWaitOk()) {
+
+            int32_t v=0;
+            testOk1(!!ret["value"].as(v));
+            testEq(v, 42);
+        }
+    }
+
+    void timeout()
+    {
+        // server not started
+
+        auto arg = initial.cloneEmpty();
+        arg["value"] = 42;
+        auto op = doCall(std::move(arg));
+        testOk1(!done.wait(2.1));
+    }
+
+    void cancel()
+    {
+        mbox.open(initial);
+        serv.start();
+
+        auto arg = initial.cloneEmpty();
+        arg["value"] = 42;
+        (void)doCall(std::move(arg));
+        testOk1(!done.wait(2.1));
+
+    }
+
+    void error()
+    {
+        mbox.open(initial);
+        serv.start();
+        fail=true;
+
+        auto arg = initial.cloneEmpty();
+        arg["value"] = 42;
+        auto op = doCall(std::move(arg));
+
+        if(testOk1(done.wait(5.0))) {
+            testThrows<client::RemoteError>([this](){
+                actual();
+            });
+        } else {
+            testSkip(1, "timeout");
+        }
+    }
+};
+
+} // namespace
+
+MAIN(testrpc)
+{
+    testPlan(12);
+    Tester().echo();
+    Tester().lazy();
+    Tester().timeout();
+    Tester().cancel();
+    Tester().error();
+    cleanup_for_valgrind();
+    return testDone();
+}