diff --git a/zig-impl/crystal/some-crystal-app/src/test-messages.cr b/zig-impl/crystal/some-crystal-app/src/test-messages.cr
new file mode 100644
index 0000000..5472246
--- /dev/null
+++ b/zig-impl/crystal/some-crystal-app/src/test-messages.cr
@@ -0,0 +1,82 @@
+require "./main.cr"
+require "./json.cr"
+require "baguette-crystal-base"
+
+# Context class, so the variables are available everywhere.
+class Context
+	class_property requests  = [] of IPC::JSON.class
+	class_property responses = [] of IPC::JSON.class
+end
+
+class IPC::JSON
+	def handle
+		raise "unimplemented"
+	end
+end
+
+IPC::JSON.message Message, 10 do
+	property content     : String?
+	property some_number : Int32?
+	def initialize(@content = nil, @some_number = nil)
+	end
+
+	def handle
+		Baguette::Log.info "message received: #{@content}, number: #{@some_number}"
+		if number = @some_number
+			::MessageReceived.new number - 1
+		else
+			::MessageReceived.new
+		end
+	end
+end
+Context.requests << Message
+
+
+IPC::JSON.message Error, 0 do
+	property reason : String
+	def initialize(@reason)
+	end
+end
+Context.responses << Error
+
+IPC::JSON.message MessageReceived, 20 do
+	property minus_one : Int32?
+	def initialize(@minus_one = nil)
+	end
+
+	def handle
+		Baguette::Log.info "<< MessageReceived (#{@minus_one})"
+	end
+end
+Context.responses << MessageReceived
+
+pp! Context.requests
+pp! Context.responses
+
+request = ::Message.new "hello this is a request", 30
+pp! request
+pp! request.to_json
+response = request.handle
+pp! response
+response.handle
+
+received_raw_message = Bytes[0x0a, 0x68, 0x65, 0x6c, 0x6c, 0x6f]
+received_message = IPCMessage::TypedMessage.deserialize received_raw_message
+pp! received_message
+if received_message.nil?
+	puts "received message: nil!!!"
+else
+	s = String.new received_message.payload.not_nil!
+	pp! s
+
+	jpayload = "{\"content\":\"hello this is a request\",\"some_number\":30}"
+	payload = Bytes.new jpayload.to_unsafe, jpayload.size
+	received_message.payload = payload
+
+	begin
+		r = Context.requests.parse_ipc_json(received_message)
+		pp! r
+	rescue e
+		puts "error while parsing JSON: #{e}"
+	end
+end