diff --git a/2019/09.cpp b/2019/09.cpp
index fa17471..c25f2c7 100644
--- a/2019/09.cpp
+++ b/2019/09.cpp
@@ -1,6 +1,8 @@
 #include <iostream>
 #include <utility>
 
+#include <doctest.h>
+
 #include <aocpp/Startup.hpp>
 #include <intcode/intcode.hpp>
 using namespace intcode;
@@ -17,6 +19,16 @@ auto Compute(Machine machine, ValueType d) -> ValueType {
 
 } // namespace
 
+TEST_SUITE("documented examples") {
+  TEST_CASE("part 1") {
+    std::vector<ValueType> pgm {109,1,204,-1,1001,100,1,100,1008,100,16,101,1006,101,0,99};
+    std::vector<ValueType> output;
+    Machine machine {pgm};
+    Run(machine, []() -> ValueType{ REQUIRE(false); return 0; }, [&](ValueType o){ output.push_back(o);});
+    REQUIRE(pgm == output);
+  }
+}
+
 auto main(int argc, char** argv) -> int {
   auto machine = Machine{ParseStream(aocpp::Startup(argc, argv))};
   std::cout << "Part 1: " << Compute(machine, 1) << std::endl;