t.Errorf("%d bytes left over after Skip(): %q", len(left), left)
	}
	if !reflect.DeepEqual(v, v2) {
		t.Errorf("MSS: %v != %v", v, v2)
	}
}

func TestMarshalUnmarshalMSSNil(t *testing.T) {
	v := MSS(nil)
	bts, err := v.MarshalMsg(nil)
	if err != nil {
		t.Fatal(err)
	}
	v2 := MSS(make(map[string]string, 1))
	left, err := v2.UnmarshalMsg(bts)
	if err != nil {
		t.Fatal(err)
	}
	if len(left) != 0 {

        final MavenSession ms = nonNull(getMavenSession());
        final MavenSession mss;
        if (repoSession != ms.getRepositorySession()) {
            mss = new MavenSession(repoSession, ms.getRequest(), ms.getResult());
        } else {
            mss = ms;
        }
        return newSession(mss, repositories);
    }

	// If the context contains a TraceParamsKey, add it to the trace path.
	v := ctx.Value(TraceParamsKey{})
	// Should match SingleHandler.Call checks.
	switch typed := v.(type) {
	case *MSS:
		trace.Path += typed.ToQuery()
	case map[string]string:
		m := MSS(typed)
		trace.Path += m.ToQuery()
	case *URLValues:
		trace.Path += typed.Values().Encode()
	case *NoPayload, *Bytes:

These must provide `msgp` serialization and deserialization.

In the examples we use a `MSS` type, which is a `map[string]string` that is `msgp` serializable.

```go
    handler := func(request *grid.MSS) (*grid.MSS, *grid.RemoteErr) {
        fmt.Println("Got request with field", request["myfield"])
        // Do something with payload

	}
	scfg.CmdLines = cmdLines
	return scfg
}

func (s *bootstrapRESTServer) VerifyHandler(params *grid.MSS) (*ServerSystemConfig, *grid.RemoteErr) {
	return getServerSystemCfg(), nil
}

var serverVerifyHandler = grid.NewSingleHandler[*grid.MSS, *ServerSystemConfig](grid.HandlerServerVerify, grid.NewMSS, func() *ServerSystemConfig { return &ServerSystemConfig{} })