WIP.

diff --git a/benchmarks/BUILD b/benchmarks/BUILD
index 87315a3..20d28dd 100644
--- a/benchmarks/BUILD
+++ b/benchmarks/BUILD

@@ -51,3 +51,35 @@
         "@com_google_protobuf//:protobuf",
     ],
 )
+
+# Size benchmarks.
+
+upb_proto_library(
+    name = "empty_upb_proto",
+    deps = ["@com_google_protobuf//:empty_proto"],
+)
+
+cc_proto_library(
+    name = "empty_cc_proto",
+    deps = ["@com_google_protobuf//:empty_proto"],
+)
+
+cc_binary(
+    name = "upb_binary",
+    testonly = 1,
+    srcs = ["upb_binary.c"],
+    deps = [
+        ":empty_upb_proto",
+    ],
+    #features = ["fully_static_link"],
+)
+
+cc_binary(
+    name = "protobuf_binary",
+    testonly = 1,
+    srcs = ["protobuf_binary.cc"],
+    deps = [
+        ":empty_cc_proto",
+    ],
+    #features = ["fully_static_link"],
+)

diff --git a/benchmarks/protobuf_binary.cc b/benchmarks/protobuf_binary.cc
new file mode 100644
index 0000000..b585aa6
--- /dev/null
+++ b/benchmarks/protobuf_binary.cc

@@ -0,0 +1,10 @@
+
+#include "google/protobuf/empty.pb.h"
+
+char buf[1];
+
+int main() {
+  google::protobuf::Empty proto;
+  proto.ParseFromArray(buf, 1);
+  proto.SerializeToArray(buf, 1);
+}

diff --git a/benchmarks/small.proto b/benchmarks/small.proto
new file mode 100644
index 0000000..cfc59c2
--- /dev/null
+++ b/benchmarks/small.proto

@@ -0,0 +1,35 @@
+// A small proto, for measuring the overhead of a minimal use of
+// protocol buffers.
+
+syntax = "proto3";
+
+option optimize_for = LITE_RUNTIME;
+option cc_enable_arenas = true;
+
+package upb_benchmark;
+
+message Person {
+  string name = 1;
+  int32 id = 2;  // Unique ID number for this person.
+  string email = 3;
+
+  enum PhoneType {
+    MOBILE = 0;
+    HOME = 1;
+    WORK = 2;
+  }
+
+  message PhoneNumber {
+    string number = 1;
+    PhoneType type = 2;
+  }
+
+  repeated PhoneNumber phones = 4;
+
+  int64 last_updated = 5;
+}
+
+// Our address book file is just one of these.
+message AddressBook {
+  repeated Person people = 1;
+}

diff --git a/benchmarks/upb_binary.c b/benchmarks/upb_binary.c
new file mode 100644
index 0000000..8e2d86b
--- /dev/null
+++ b/benchmarks/upb_binary.c

@@ -0,0 +1,12 @@
+
+#include "google/protobuf/empty.upb.h"
+
+char buf[1];
+
+int main() {
+  upb_arena *arena = upb_arena_new();
+  size_t size;
+  google_protobuf_Empty *proto = google_protobuf_Empty_parse(buf, 1, arena);
+  google_protobuf_Empty_serialize(proto, arena, &size);
+  return 0;
+}