diff --git a/.obj-rt/cutils.bytecode.lto.o b/.obj-rt/cutils.bytecode.lto.o
new file mode 100644
index 000000000..e3de041bd
Binary files /dev/null and b/.obj-rt/cutils.bytecode.lto.o differ
diff --git a/.obj-rt/cutils.bytecode.lto.o.d b/.obj-rt/cutils.bytecode.lto.o.d
new file mode 100644
index 000000000..4025fc9e8
--- /dev/null
+++ b/.obj-rt/cutils.bytecode.lto.o.d
@@ -0,0 +1 @@
+.obj-rt/cutils.bytecode.lto.o: cutils.c cutils.h
diff --git a/.obj-rt/dtoa.bytecode.lto.o b/.obj-rt/dtoa.bytecode.lto.o
new file mode 100644
index 000000000..439d135ca
Binary files /dev/null and b/.obj-rt/dtoa.bytecode.lto.o differ
diff --git a/.obj-rt/dtoa.bytecode.lto.o.d b/.obj-rt/dtoa.bytecode.lto.o.d
new file mode 100644
index 000000000..18ab15d87
--- /dev/null
+++ b/.obj-rt/dtoa.bytecode.lto.o.d
@@ -0,0 +1 @@
+.obj-rt/dtoa.bytecode.lto.o: dtoa.c cutils.h dtoa.h
diff --git a/.obj-rt/libregexp.bytecode.lto.o b/.obj-rt/libregexp.bytecode.lto.o
new file mode 100644
index 000000000..54b8e05cd
Binary files /dev/null and b/.obj-rt/libregexp.bytecode.lto.o differ
diff --git a/.obj-rt/libregexp.bytecode.lto.o.d b/.obj-rt/libregexp.bytecode.lto.o.d
new file mode 100644
index 000000000..27ad3a9ef
--- /dev/null
+++ b/.obj-rt/libregexp.bytecode.lto.o.d
@@ -0,0 +1,2 @@
+.obj-rt/libregexp.bytecode.lto.o: libregexp.c cutils.h libregexp.h \
+ libunicode.h libregexp-opcode.h
diff --git a/.obj-rt/libunicode.bytecode.lto.o b/.obj-rt/libunicode.bytecode.lto.o
new file mode 100644
index 000000000..bb5ebfddf
Binary files /dev/null and b/.obj-rt/libunicode.bytecode.lto.o differ
diff --git a/.obj-rt/libunicode.bytecode.lto.o.d b/.obj-rt/libunicode.bytecode.lto.o.d
new file mode 100644
index 000000000..a5c5103dc
--- /dev/null
+++ b/.obj-rt/libunicode.bytecode.lto.o.d
@@ -0,0 +1,2 @@
+.obj-rt/libunicode.bytecode.lto.o: libunicode.c cutils.h libunicode.h \
+ libunicode-table.h
diff --git a/.obj-rt/quickjs-libc.bytecode.lto.o b/.obj-rt/quickjs-libc.bytecode.lto.o
new file mode 100644
index 000000000..ed6ef0664
Binary files /dev/null and b/.obj-rt/quickjs-libc.bytecode.lto.o differ
diff --git a/.obj-rt/quickjs-libc.bytecode.lto.o.d b/.obj-rt/quickjs-libc.bytecode.lto.o.d
new file mode 100644
index 000000000..6851cf8d7
--- /dev/null
+++ b/.obj-rt/quickjs-libc.bytecode.lto.o.d
@@ -0,0 +1,2 @@
+.obj-rt/quickjs-libc.bytecode.lto.o: quickjs-libc.c cutils.h list.h \
+ quickjs-libc.h quickjs.h
diff --git a/.obj-rt/quickjs.bytecode.lto.o b/.obj-rt/quickjs.bytecode.lto.o
new file mode 100644
index 000000000..e8c32aceb
Binary files /dev/null and b/.obj-rt/quickjs.bytecode.lto.o differ
diff --git a/.obj-rt/quickjs.bytecode.lto.o.d b/.obj-rt/quickjs.bytecode.lto.o.d
new file mode 100644
index 000000000..2a5d905e1
--- /dev/null
+++ b/.obj-rt/quickjs.bytecode.lto.o.d
@@ -0,0 +1,2 @@
+.obj-rt/quickjs.bytecode.lto.o: quickjs.c cutils.h list.h quickjs.h \
+ libregexp.h libunicode.h dtoa.h quickjs-atom.h quickjs-opcode.h
diff --git a/Makefile b/Makefile
index 95885e374..ade95402d 100644
--- a/Makefile
+++ b/Makefile
@@ -59,6 +59,7 @@ TEST262_COMMIT?=5c8206929d81b2d3d727ca6aac56c18358c8d790
 TEST262_SINCE?=2025-09-01
 
 OBJDIR=.obj
+OBJDIR_RT=.obj-rt
 
 ifdef CONFIG_ASAN
 OBJDIR:=$(OBJDIR)/asan
@@ -257,6 +258,10 @@ LIBS+=$(EXTRA_LIBS)
 $(OBJDIR):
 	mkdir -p $(OBJDIR) $(OBJDIR)/examples $(OBJDIR)/tests
 
+$(OBJDIR_RT):
+	mkdir -p $(OBJDIR_RT)
+	mkdir -p $(OBJDIR_RT)/examples $(OBJDIR_RT)/tests
+
 qjs$(EXE): $(QJS_OBJS)
 	$(CC) $(LDFLAGS) $(LDEXPORT) -o $@ $^ $(LIBS)
 
@@ -311,6 +316,15 @@ endif # CONFIG_LTO
 libquickjs.fuzz.a: $(patsubst %.o, %.fuzz.o, $(QJS_LIB_OBJS))
 	$(AR) rcs $@ $^
 
+QJS_BYTECODE_OBJS=$(patsubst $(OBJDIR)/%.o, $(OBJDIR_RT)/%.bytecode.o, $(QJS_LIB_OBJS))
+QJS_BYTECODE_LTO_OBJS=$(patsubst $(OBJDIR)/%.o, $(OBJDIR_RT)/%.bytecode.lto.o, $(QJS_LIB_OBJS))
+
+libquickjs-bytecode.a: $(QJS_BYTECODE_OBJS)
+	$(AR) rcs $@ $^
+
+libquickjs-bytecode.lto.a: $(QJS_BYTECODE_LTO_OBJS)
+	$(AR) rcs $@ $^
+
 repl.c: $(QJSC) repl.js
 	$(QJSC) -s -c -o $@ -m repl.js
 
@@ -353,6 +367,12 @@ $(OBJDIR)/%.fuzz.o: %.c | $(OBJDIR)
 $(OBJDIR)/%.check.o: %.c | $(OBJDIR)
 	$(CC) $(CFLAGS) -DCONFIG_CHECK_JSVALUE -c -o $@ $<
 
+$(OBJDIR_RT)/%.bytecode.o: %.c | $(OBJDIR_RT)
+	$(CC) $(CFLAGS_NOLTO) -DCONFIG_BYTECODE_ONLY_RUNTIME -MMD -MF $(OBJDIR_RT)/$(@F).d -c -o $@ $<
+
+$(OBJDIR_RT)/%.bytecode.lto.o: %.c | $(OBJDIR_RT)
+	$(CC) $(CFLAGS_OPT) -DCONFIG_BYTECODE_ONLY_RUNTIME -MMD -MF $(OBJDIR_RT)/$(@F).d -c -o $@ $<
+
 regexp_test: libregexp.c libunicode.c cutils.c
 	$(CC) $(LDFLAGS) $(CFLAGS) -DTEST -o $@ libregexp.c libunicode.c cutils.c $(LIBS)
 
@@ -374,8 +394,10 @@ install: all
 	install -m755 qjs$(EXE) qjsc$(EXE) "$(DESTDIR)$(PREFIX)/bin"
 	mkdir -p "$(DESTDIR)$(PREFIX)/lib/quickjs"
 	install -m644 libquickjs.a "$(DESTDIR)$(PREFIX)/lib/quickjs"
+	install -m644 libquickjs-bytecode.a "$(DESTDIR)$(PREFIX)/lib/quickjs"
 ifdef CONFIG_LTO
 	install -m644 libquickjs.lto.a "$(DESTDIR)$(PREFIX)/lib/quickjs"
+	install -m644 libquickjs-bytecode.lto.a "$(DESTDIR)$(PREFIX)/lib/quickjs"
 endif
 	mkdir -p "$(DESTDIR)$(PREFIX)/include/quickjs"
 	install -m644 quickjs.h quickjs-libc.h "$(DESTDIR)$(PREFIX)/include/quickjs"
@@ -511,6 +533,18 @@ testall: all test microbench test2o test2
 
 testall-complete: testall
 
+test-bytecode-runtime: libquickjs-bytecode.lto.a qjsc$(EXE) qjs$(EXE)
+	$(QJSC) -fno-eval -fno-regexp -fno-json -fno-module-loader \
+	        -o /tmp/test-bytecode-rt tests/test_bytecode_runtime.js
+	@nm /tmp/test-bytecode-rt | grep -E ' T (__JS_EvalInternal|js_parse_|js_compile_|js_evalScript|js_loadScript|js_std_parseExtJSON|js_worker_ctor)' \
+	    && (echo "FAIL: forbidden symbols found in bytecode-only binary" && exit 1) \
+	    || echo "PASS: no forbidden symbols"
+	@/tmp/test-bytecode-rt > /tmp/test-bytecode-rt.out
+	@./qjs$(EXE) tests/test_bytecode_runtime.js > /tmp/test-bytecode-rt.expected
+	@diff /tmp/test-bytecode-rt.out /tmp/test-bytecode-rt.expected \
+	    && echo "PASS: bytecode round-trip equivalence" \
+	    || (echo "FAIL: bytecode round-trip equivalence" && exit 1)
+
 node-test:
 	node tests/test_closure.js
 	node tests/test_language.js
diff --git a/qjsc.c b/qjsc.c
index e55ca61ce..4d1a13b3d 100644
--- a/qjsc.c
+++ b/qjsc.c
@@ -21,6 +21,10 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+#ifdef CONFIG_BYTECODE_ONLY_RUNTIME
+#error "qjsc must be built with the full QuickJS engine"
+#endif
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdarg.h>
@@ -79,6 +83,15 @@ static const FeatureEntry feature_list[] = {
     { "weakref", "WeakRef" },
 };
 
+#define FE_MASK(i) ((uint64_t)1 << (i))
+#define BYTECODE_ONLY_TRIGGER_MASK \
+    (FE_MASK(1) | FE_MASK(3) | FE_MASK(4) | FE_MASK(FE_MODULE_LOADER))
+
+static BOOL runtime_needs_parser(void)
+{
+    return (feature_bitmap & BYTECODE_ONLY_TRIGGER_MASK) != 0;
+}
+
 void namelist_add(namelist_t *lp, const char *name, const char *short_name,
                   int flags)
 {
@@ -476,7 +489,10 @@ static int output_executable(const char *out_filename, const char *cfilename,
     }
 
     lto_suffix = "";
-    bn_suffix = "";
+    if (runtime_needs_parser())
+        bn_suffix = "";
+    else
+        bn_suffix = "-bytecode";
 
     arg = argv;
     *arg++ = CONFIG_CC;
diff --git a/quickjs-libc.c b/quickjs-libc.c
index c24b6d53e..c33fdae21 100644
--- a/quickjs-libc.c
+++ b/quickjs-libc.c
@@ -431,6 +431,7 @@ uint8_t *js_load_file(JSContext *ctx, size_t *pbuf_len, const char *filename)
 }
 
 /* load and evaluate a file */
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
 static JSValue js_loadScript(JSContext *ctx, JSValueConst this_val,
                              int argc, JSValueConst *argv)
 {
@@ -454,6 +455,7 @@ static JSValue js_loadScript(JSContext *ctx, JSValueConst this_val,
     JS_FreeCString(ctx, filename);
     return ret;
 }
+#endif
 
 /* load a file as a UTF-8 encoded string */
 static JSValue js_std_loadFile(JSContext *ctx, JSValueConst this_val,
@@ -694,6 +696,7 @@ JSModuleDef *js_module_loader(JSContext *ctx,
             return NULL;
         }
         res = js_module_test_json(ctx, attributes);
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
         if (has_suffix(module_name, ".json") || res > 0) {
             /* compile as JSON or JSON5 depending on "type" */
             JSValue val;
@@ -723,6 +726,12 @@ JSModuleDef *js_module_loader(JSContext *ctx,
             m = JS_VALUE_GET_PTR(func_val);
             JS_FreeValue(ctx, func_val);
         }
+#else
+        js_free(ctx, buf);
+        JS_ThrowReferenceError(ctx, "could not load module filename '%s' (bytecode only runtime)",
+                               module_name);
+        return NULL;
+#endif
     }
     return m;
 }
@@ -870,6 +879,7 @@ static int get_bool_option(JSContext *ctx, BOOL *pbool,
     return 0;
 }
 
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
 static JSValue js_evalScript(JSContext *ctx, JSValueConst this_val,
                              int argc, JSValueConst *argv)
 {
@@ -918,6 +928,7 @@ static JSValue js_evalScript(JSContext *ctx, JSValueConst this_val,
     }
     return ret;
 }
+#endif
 
 static JSClassID js_std_file_class_id;
 
@@ -957,6 +968,7 @@ static JSValue js_std_strerror(JSContext *ctx, JSValueConst this_val,
     return JS_NewString(ctx, strerror(err));
 }
 
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
 static JSValue js_std_parseExtJSON(JSContext *ctx, JSValueConst this_val,
                                    int argc, JSValueConst *argv)
 {
@@ -971,6 +983,7 @@ static JSValue js_std_parseExtJSON(JSContext *ctx, JSValueConst this_val,
     JS_FreeCString(ctx, str);
     return obj;
 }
+#endif
 
 static JSValue js_new_std_file(JSContext *ctx, FILE *f,
                                BOOL close_in_finalizer,
@@ -1640,8 +1653,10 @@ static const JSCFunctionListEntry js_std_error_props[] = {
 static const JSCFunctionListEntry js_std_funcs[] = {
     JS_CFUNC_DEF("exit", 1, js_std_exit ),
     JS_CFUNC_DEF("gc", 0, js_std_gc ),
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
     JS_CFUNC_DEF("evalScript", 1, js_evalScript ),
     JS_CFUNC_DEF("loadScript", 1, js_loadScript ),
+#endif
     JS_CFUNC_DEF("getenv", 1, js_std_getenv ),
     JS_CFUNC_DEF("setenv", 1, js_std_setenv ),
     JS_CFUNC_DEF("unsetenv", 1, js_std_unsetenv ),
@@ -1649,7 +1664,9 @@ static const JSCFunctionListEntry js_std_funcs[] = {
     JS_CFUNC_DEF("urlGet", 1, js_std_urlGet ),
     JS_CFUNC_DEF("loadFile", 1, js_std_loadFile ),
     JS_CFUNC_DEF("strerror", 1, js_std_strerror ),
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
     JS_CFUNC_DEF("parseExtJSON", 1, js_std_parseExtJSON ),
+#endif
 
     /* FILE I/O */
     JS_CFUNC_DEF("open", 2, js_std_open ),
@@ -3578,6 +3595,7 @@ static JSClassDef js_worker_class = {
     .gc_mark = js_worker_mark,
 };
 
+#if defined(USE_WORKER) && !defined(CONFIG_BYTECODE_ONLY_RUNTIME)
 static void *worker_func(void *opaque)
 {
     WorkerFuncArgs *args = opaque;
@@ -3743,6 +3761,7 @@ static JSValue js_worker_ctor(JSContext *ctx, JSValueConst new_target,
     JS_FreeValue(ctx, obj);
     return JS_EXCEPTION;
 }
+#endif
 
 static JSValue js_worker_postMessage(JSContext *ctx, JSValueConst this_val,
                                      int argc, JSValueConst *argv)
@@ -3976,7 +3995,7 @@ static int js_os_init(JSContext *ctx, JSModuleDef *m)
 {
     os_poll_func = js_os_poll;
 
-#ifdef USE_WORKER
+#if defined(USE_WORKER) && !defined(CONFIG_BYTECODE_ONLY_RUNTIME)
     {
         JSRuntime *rt = JS_GetRuntime(ctx);
         JSThreadState *ts = JS_GetRuntimeOpaque(rt);
@@ -4002,7 +4021,7 @@ static int js_os_init(JSContext *ctx, JSModuleDef *m)
 
         JS_SetModuleExport(ctx, m, "Worker", obj);
     }
-#endif /* USE_WORKER */
+#endif /* USE_WORKER && !CONFIG_BYTECODE_ONLY_RUNTIME */
 
     return JS_SetModuleExportList(ctx, m, js_os_funcs,
                                   countof(js_os_funcs));
@@ -4015,7 +4034,7 @@ JSModuleDef *js_init_module_os(JSContext *ctx, const char *module_name)
     if (!m)
         return NULL;
     JS_AddModuleExportList(ctx, m, js_os_funcs, countof(js_os_funcs));
-#ifdef USE_WORKER
+#if defined(USE_WORKER) && !defined(CONFIG_BYTECODE_ONLY_RUNTIME)
     JS_AddModuleExport(ctx, m, "Worker");
 #endif
     return m;
@@ -4087,8 +4106,10 @@ void js_std_add_helpers(JSContext *ctx, int argc, char **argv)
 
     JS_SetPropertyStr(ctx, global_obj, "print",
                       JS_NewCFunction(ctx, js_print, "print", 1));
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
     JS_SetPropertyStr(ctx, global_obj, "__loadScript",
                       JS_NewCFunction(ctx, js_loadScript, "__loadScript", 1));
+#endif
 
     JS_FreeValue(ctx, global_obj);
 }
diff --git a/quickjs.c b/quickjs.c
index 2b33bfa5f..16c6bf96f 100644
--- a/quickjs.c
+++ b/quickjs.c
@@ -1195,8 +1195,10 @@ static int JS_ToInt32Free(JSContext *ctx, int32_t *pres, JSValue val);
 static int JS_ToFloat64Free(JSContext *ctx, double *pres, JSValue val);
 static int JS_ToUint8ClampFree(JSContext *ctx, int32_t *pres, JSValue val);
 static JSValue js_new_string8_len(JSContext *ctx, const char *buf, int len);
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
 static JSValue js_compile_regexp(JSContext *ctx, JSValueConst pattern,
                                  JSValueConst flags);
+#endif
 static JSValue JS_NewRegexp(JSContext *ctx, JSValue pattern, JSValue bc);
 static void gc_decref(JSRuntime *rt);
 static int JS_NewClass1(JSRuntime *rt, JSClassID class_id,
@@ -35439,6 +35441,7 @@ static int add_global_variables(JSContext *ctx, JSFunctionDef *fd)
 /* create a function object from a function definition. The function
    definition is freed. All the child functions are also created. It
    must be done this way to resolve all the variables. */
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
 static JSValue js_create_function(JSContext *ctx, JSFunctionDef *fd)
 {
     JSValue func_obj;
@@ -35697,6 +35700,7 @@ static JSValue js_create_function(JSContext *ctx, JSFunctionDef *fd)
     js_free_function_def(ctx, fd);
     return JS_EXCEPTION;
 }
+#endif
 
 static void free_function_bytecode(JSRuntime *rt, JSFunctionBytecode *b)
 {
@@ -36493,6 +36497,7 @@ static __exception int js_parse_function_decl(JSParseState *s,
                                    JS_PARSE_EXPORT_NONE, NULL);
 }
 
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
 static __exception int js_parse_program(JSParseState *s)
 {
     JSFunctionDef *fd = s->cur_func;
@@ -36544,6 +36549,7 @@ static __exception int js_parse_program(JSParseState *s)
 
     return 0;
 }
+#endif
 
 static void js_parse_init(JSContext *ctx, JSParseState *s,
                           const char *input, size_t input_len,
@@ -36603,6 +36609,7 @@ JSValue JS_EvalFunction(JSContext *ctx, JSValue fun_obj)
 }
 
 /* 'input' must be zero terminated i.e. input[input_len] = '\0'. */
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
 static JSValue __JS_EvalInternal(JSContext *ctx, JSValueConst this_obj,
                                  const char *input, size_t input_len,
                                  const char *filename, int flags, int scope_idx)
@@ -36717,6 +36724,7 @@ static JSValue __JS_EvalInternal(JSContext *ctx, JSValueConst this_obj,
         JS_FreeValue(ctx, JS_MKPTR(JS_TAG_MODULE, m));
     return JS_EXCEPTION;
 }
+#endif
 
 /* the indirection is needed to make 'eval' optional */
 static JSValue JS_EvalInternal(JSContext *ctx, JSValueConst this_obj,
@@ -46870,6 +46878,7 @@ static void js_regexp_finalizer(JSRuntime *rt, JSValue val)
 }
 
 /* create a string containing the RegExp bytecode */
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
 static JSValue js_compile_regexp(JSContext *ctx, JSValueConst pattern,
                                  JSValueConst flags)
 {
@@ -46947,6 +46956,7 @@ static JSValue js_compile_regexp(JSContext *ctx, JSValueConst pattern,
     js_free(ctx, re_bytecode_buf);
     return ret;
 }
+#endif
 
 /* fast regexp creation */
 static JSValue JS_NewRegexp(JSContext *ctx, JSValue pattern, JSValue bc)
@@ -47103,7 +47113,11 @@ static JSValue js_regexp_constructor(JSContext *ctx, JSValueConst new_target,
     obj = js_create_from_ctor(ctx, new_target, JS_CLASS_REGEXP);
     if (JS_IsException(obj))
         goto fail;
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
     bc = js_compile_regexp(ctx, pattern, flags);
+#else
+    bc = JS_UNDEFINED;
+#endif
     if (JS_IsException(bc))
         goto fail;
     JS_FreeValue(ctx, flags);
@@ -47142,7 +47156,11 @@ static JSValue js_regexp_compile(JSContext *ctx, JSValueConst this_val,
             pattern = JS_ToString(ctx, pattern1);
         if (JS_IsException(pattern))
             goto fail;
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
         bc = js_compile_regexp(ctx, pattern, flags1);
+#else
+        bc = JS_UNDEFINED;
+#endif
         if (JS_IsException(bc))
             goto fail;
     }
@@ -48566,7 +48584,9 @@ static const JSCFunctionListEntry js_regexp_string_iterator_proto_funcs[] = {
 
 void JS_AddIntrinsicRegExpCompiler(JSContext *ctx)
 {
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
     ctx->compile_regexp = js_compile_regexp;
+#endif
 }
 
 int JS_AddIntrinsicRegExp(JSContext *ctx)
@@ -55479,7 +55499,9 @@ int JS_AddIntrinsicDate(JSContext *ctx)
 
 int JS_AddIntrinsicEval(JSContext *ctx)
 {
+#ifndef CONFIG_BYTECODE_ONLY_RUNTIME
     ctx->eval_internal = __JS_EvalInternal;
+#endif
     return 0;
 }
 
diff --git a/tests/test_bytecode_runtime.js b/tests/test_bytecode_runtime.js
new file mode 100644
index 000000000..660ea3fc7
--- /dev/null
+++ b/tests/test_bytecode_runtime.js
@@ -0,0 +1,35 @@
+
+console.log("Hello from bytecode runtime!");
+
+function fib(n) {
+    if (n <= 1) return n;
+    return fib(n - 1) + fib(n - 2);
+}
+
+console.log("fib(10) =", fib(10));
+
+const obj = {
+    a: 1,
+    b: [1, 2, 3],
+    c: { d: "hello" }
+};
+
+console.log("obj.c.d =", obj.c.d);
+
+// test Function.prototype.toString
+function testFunc() { return 42; }
+console.log("testFunc.toString().length > 0:", testFunc.toString().length > 0);
+
+// test class
+class Point {
+    constructor(x, y) {
+        this.x = x;
+        this.y = y;
+    }
+    toString() {
+        return `(${this.x}, ${this.y})`;
+    }
+}
+
+const p = new Point(10, 20);
+console.log("p.toString() =", p.toString());