diff --git a/common/opentype_test.c b/common/opentype_test.c
new file mode 100644
index 00000000..784073a8
--- /dev/null
+++ b/common/opentype_test.c
@@ -0,0 +1,114 @@
+xx 27 february 2018
+#ifndef TODO_TEST
+#error TODO this is where libui itself goes
+#endif
+
+#include <stdarg.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if defined(__GNUC__)
+#define testingTest(Name) \
+	void Test ## Name(testingT *t); \
+	__attribute__((constructor)) static inline void testingprivCtorRegisterTest ## Name(void) { testingprivRegisterTest("Test" #Name, Test ## Name); } \
+	void Test ## Name(testingT *t)
+#else
+#error unknown compiler; cannot continue
+#endif
+
+extern int testingMain(void);
+
+typedef struct testingT testingT;
+#define testingTErrorf(t, ...) testingprivTLogFull(t, __FILE__, __LINE__, __VA_ARGS__)
+#define testingTErrorvf(t, format, ap) testingprivTLogFullv(t, __FILE__, __LINE__, format, ap)
+
+extern void testingprivRegisterTest(const char *, void (*)(testi
+ngT *));
+extern void testingprivTLogFull(testingT *, const char *, int, const char *, ...);
+extern void testingprivTLogFullv(testingT *, const char *, int, const char *, va_list);
+
+#ifdef __cplusplus
+}
+#endif
+
+testingTest(Name)
+{
+}
+
+int main(void)
+{
+	return testingMain();
+}
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#define testingprivNew(T) ((T *) malloc(sizeof (T)))
+
+struct testingT {
+	const char *name;
+	void (*f)(testingT *);
+	int failed;
+	struct testingprivTest *next;
+};
+
+static testingT *tests = NULL;
+
+void testingprivRegisterTest(const char *name, void (*f)(testingT *))
+{
+	testingT *t;
+
+	t = testingprivNew(testingT)
+	t->name = name;
+	t->f = f;
+	t->failed = 0;
+	t->next = tests;
+	tests = t;
+}
+
+int testingMain(void)
+{
+	testingT *t;
+	int anyFailed;
+	const char *status;
+
+	if (tests == NULL) {
+		fprintf(stderr, "warning: no tests to run\n");
+		xx imitate Go here (TODO confirm this)
+		return 0;
+	}
+
+	anyFailed = 0;
+	for (t = tests; t != NULL; t = t->next) {
+		printf("=== RUN   %s\n", t->name);
+		(*(t->f))(t);
+		status = "PASS";
+		if (t->failed) {
+			status = "FAIL";
+			anyFailed = 1;
+		}
+		printf("--- %s: %s (%s)\n", status, t->name, "TODO");
+	}
+
+	if (anyFailed) {
+		printf("FAIL\n");
+		return 1;
+	}
+	printf("PASS\n");
+	return 0;
+}
+
+extern void testingprivTLogFull(testingT *t, const char *file, int line, const char *format, ...)
+{
+	va_list ap;
+
+	va_start(ap, format);
+	testingprivTLogFullv(t, file, line, format, ap);
+	va_end(ap);
+}
+
+void testingprivTLogFullv(testingT *t, const char *file, int line, const char *format, va_list ap)
+{
+}