diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d7d897a1c..cad6e54b5 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -643,11 +643,14 @@ jobs:
           - name: clang+sanitize
             args: >-
               "-Db_sanitize=address,undefined"
+              "-Db_lundef=false"
             extra_envs:
               CC: clang
               CXX: clang++
           - name: clang+msan
-            args: -Db_sanitize=memory
+            args: >-
+              "-Db_sanitize=memory"
+              "-Db_lundef=false"
             extra_envs:
               CC: clang
               CXX: clang++
@@ -657,6 +660,7 @@ jobs:
           - name: clang-cl+sanitize
             args: >-
               "-Db_sanitize=address,undefined"
+              "-Db_lundef=false"
             extra_envs:
               CC: clang-cl
               CXX: clang-cl
diff --git a/CMakeLists.txt b/CMakeLists.txt
index cf6bf1754..5cc76bd04 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,6 +10,9 @@ set(CMAKE_C_STANDARD_REQUIRED ON)
 set(CMAKE_C_EXTENSIONS ON)
 set(CMAKE_C_STANDARD 11)
 
+# Used to properly define QJS_LIBC_EXTERN.
+add_compile_definitions(QUICKJS_NG_BUILD)
+
 # MINGW doesn't exist in older cmake versions, newer versions don't know
 # about CMAKE_COMPILER_IS_MINGW, and there is no unique CMAKE_C_COMPILER_ID
 # for mingw-based compilers...
@@ -232,7 +235,7 @@ endif()
 xoption(QJS_BUILD_LIBC "Build standard library modules as part of the library" OFF)
 macro(add_qjs_libc_if_needed target)
     if(NOT QJS_BUILD_LIBC)
-        target_sources(${target} PRIVATE quickjs-libc.c)
+        target_link_libraries(${target} PRIVATE qjs-libc)
     endif()
 endmacro()
 macro(add_static_if_needed target)
@@ -245,7 +248,6 @@ macro(add_static_if_needed target)
 endmacro()
 
 set(qjs_sources
-    cutils.c
     dtoa.c
     libregexp.c
     libunicode.c
@@ -254,6 +256,8 @@ set(qjs_sources
 
 if(QJS_BUILD_LIBC)
     list(APPEND qjs_sources quickjs-libc.c)
+    # The definition must be added to the entire project.
+    add_compile_definitions(QJS_BUILD_LIBC)
 endif()
 list(APPEND qjs_defines _GNU_SOURCE)
 if(WIN32)
@@ -278,13 +282,37 @@ if(M_LIBRARIES OR CMAKE_C_COMPILER_ID STREQUAL "TinyCC")
     list(APPEND qjs_libs m)
 endif()
 
+add_library(cutils STATIC cutils.c)
+target_compile_definitions(cutils PRIVATE ${qjs_defines})
+target_link_libraries(cutils PRIVATE ${qjs_libs})
+
 add_library(qjs ${qjs_sources})
-target_compile_definitions(qjs PRIVATE ${qjs_defines})
+target_compile_definitions(qjs PRIVATE ${qjs_defines} QUICKJS_NG_QJS_INTERNAL)
 target_include_directories(qjs PUBLIC
     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
     $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
 )
 target_link_libraries(qjs PUBLIC ${qjs_libs})
+target_link_libraries(qjs PRIVATE $<BUILD_INTERFACE:cutils>)
+if(QJS_BUILD_EXAMPLES)
+    # We shouldn't really support building examples with static qjs..
+    # Anyways, this is required for fib.so and point.so to link properly.
+    set_target_properties(qjs PROPERTIES POSITION_INDEPENDENT_CODE ON)
+endif()
+
+# Pass a compiler definition so that Windows gets its declspec's right.
+get_target_property(QJS_LIB_TYPE qjs TYPE)
+if(QJS_LIB_TYPE STREQUAL "SHARED_LIBRARY")
+    # We use PUBLIC here because we want the consumers to also have this
+    # definition.
+    target_compile_definitions(qjs PUBLIC QUICKJS_NG_DLL)
+endif()
+
+if(NOT QJS_BUILD_LIBC)
+    add_library(qjs-libc STATIC quickjs-libc.c)
+    target_compile_definitions(qjs-libc PRIVATE ${qjs_defines})
+    target_link_libraries(qjs-libc PRIVATE ${qjs_libs} qjs cutils)
+endif()
 
 if(EMSCRIPTEN)
     add_executable(qjs_wasm ${qjs_sources})
@@ -301,7 +329,7 @@ if(EMSCRIPTEN)
         -sEXPORTED_RUNTIME_METHODS=ccall,cwrap
     )
     target_compile_definitions(qjs_wasm PRIVATE ${qjs_defines})
-    target_link_libraries(qjs_wasm m)
+    target_link_libraries(qjs_wasm PRIVATE m)
 endif()
 
 
@@ -314,7 +342,7 @@ add_executable(qjsc
 add_qjs_libc_if_needed(qjsc)
 add_static_if_needed(qjsc)
 target_compile_definitions(qjsc PRIVATE ${qjs_defines})
-target_link_libraries(qjsc qjs)
+target_link_libraries(qjsc PRIVATE qjs cutils)
 
 
 # QuickJS CLI
@@ -331,7 +359,7 @@ set_target_properties(qjs_exe PROPERTIES
     OUTPUT_NAME "qjs"
 )
 target_compile_definitions(qjs_exe PRIVATE ${qjs_defines})
-target_link_libraries(qjs_exe qjs)
+target_link_libraries(qjs_exe PRIVATE qjs cutils)
 if(NOT WIN32)
     set_target_properties(qjs_exe PROPERTIES ENABLE_EXPORTS TRUE)
 endif()
@@ -339,9 +367,9 @@ if(QJS_BUILD_CLI_WITH_MIMALLOC OR QJS_BUILD_CLI_WITH_STATIC_MIMALLOC)
     find_package(mimalloc REQUIRED)
     # Upstream mimalloc doesn't provide a way to know if both libraries are supported.
     if(QJS_BUILD_CLI_WITH_STATIC_MIMALLOC)
-        target_link_libraries(qjs_exe mimalloc-static)
+        target_link_libraries(qjs_exe PRIVATE mimalloc-static)
     else()
-        target_link_libraries(qjs_exe mimalloc)
+        target_link_libraries(qjs_exe PRIVATE mimalloc)
     endif()
 endif()
 
@@ -354,7 +382,7 @@ if(NOT EMSCRIPTEN)
     )
     add_qjs_libc_if_needed(run-test262)
     target_compile_definitions(run-test262 PRIVATE ${qjs_defines})
-    target_link_libraries(run-test262 qjs)
+    target_link_libraries(run-test262 PRIVATE qjs cutils)
 endif()
 
 # Interrupt test
@@ -364,17 +392,17 @@ add_executable(api-test
     api-test.c
 )
 target_compile_definitions(api-test PRIVATE ${qjs_defines})
-target_link_libraries(api-test qjs)
+target_link_libraries(api-test PRIVATE qjs cutils)
 
 # Unicode generator
 #
 
 add_executable(unicode_gen EXCLUDE_FROM_ALL
-    cutils.c
     libunicode.c
     unicode_gen.c
 )
 target_compile_definitions(unicode_gen PRIVATE ${qjs_defines})
+target_link_libraries(unicode_gen PRIVATE cutils)
 
 add_executable(function_source
     gen/function_source.c
@@ -382,7 +410,7 @@ add_executable(function_source
 add_qjs_libc_if_needed(function_source)
 target_include_directories(function_source PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
 target_compile_definitions(function_source PRIVATE ${qjs_defines})
-target_link_libraries(function_source qjs)
+target_link_libraries(function_source PRIVATE qjs)
 
 # Examples
 #
@@ -394,7 +422,7 @@ if(QJS_BUILD_EXAMPLES)
     add_qjs_libc_if_needed(hello)
     target_include_directories(hello PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
     target_compile_definitions(hello PRIVATE ${qjs_defines})
-    target_link_libraries(hello qjs)
+    target_link_libraries(hello PRIVATE qjs)
 
     add_executable(hello_module
         gen/hello_module.c
@@ -402,17 +430,16 @@ if(QJS_BUILD_EXAMPLES)
     add_qjs_libc_if_needed(hello_module)
     target_include_directories(hello_module PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
     target_compile_definitions(hello_module PRIVATE ${qjs_defines})
-    target_link_libraries(hello_module qjs)
+    target_link_libraries(hello_module PRIVATE qjs)
 
     add_library(fib MODULE examples/fib.c)
     set_target_properties(fib PROPERTIES
         PREFIX ""
         C_VISIBILITY_PRESET default
     )
-    target_compile_definitions(fib PRIVATE JS_SHARED_LIBRARY)
-    if(WIN32)
-        target_link_libraries(fib qjs)
-    elseif(APPLE)
+    target_link_libraries(fib PRIVATE qjs)
+    target_compile_definitions(fib PRIVATE QUICKJS_NG_MODULE_BUILD)
+    if(APPLE)
         target_link_options(fib PRIVATE -undefined dynamic_lookup)
     endif()
 
@@ -421,10 +448,9 @@ if(QJS_BUILD_EXAMPLES)
         PREFIX ""
         C_VISIBILITY_PRESET default
     )
-    target_compile_definitions(point PRIVATE JS_SHARED_LIBRARY)
-    if(WIN32)
-        target_link_libraries(point qjs)
-    elseif(APPLE)
+    target_link_libraries(point PRIVATE qjs)
+    target_compile_definitions(point PRIVATE QUICKJS_NG_MODULE_BUILD)
+    if(APPLE)
         target_link_options(point PRIVATE -undefined dynamic_lookup)
     endif()
 
@@ -434,8 +460,8 @@ if(QJS_BUILD_EXAMPLES)
     )
     add_qjs_libc_if_needed(test_fib)
     target_include_directories(test_fib PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
-    target_compile_definitions(test_fib PRIVATE ${qjs_defines})
-    target_link_libraries(test_fib qjs)
+    target_compile_definitions(test_fib PRIVATE ${qjs_defines} QUICKJS_NG_MODULE_BUILD)
+    target_link_libraries(test_fib PRIVATE qjs)
 endif()
 
 # Install target
diff --git a/examples/fib.c b/examples/fib.c
index b965acc5b..a9eb29d92 100644
--- a/examples/fib.c
+++ b/examples/fib.c
@@ -21,7 +21,8 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-#include "../quickjs.h"
+
+#include <quickjs.h>
 
 #define countof(x) (sizeof(x) / sizeof((x)[0]))
 
@@ -55,21 +56,7 @@ static int js_fib_init(JSContext *ctx, JSModuleDef *m)
                                   countof(js_fib_funcs));
 }
 
-#ifdef JS_SHARED_LIBRARY
-#define JS_INIT_MODULE js_init_module
-#else
-#define JS_INIT_MODULE js_init_module_fib
-#endif
-
-#ifndef JS_EXTERN
-#ifdef _WIN32
-#define JS_EXTERN __declspec(dllexport)
-#else
-#define JS_EXTERN
-#endif
-#endif
-
-JS_EXTERN JSModuleDef *JS_INIT_MODULE(JSContext *ctx, const char *module_name)
+JS_MODULE_EXTERN JSModuleDef *js_init_module(JSContext *ctx, const char *module_name)
 {
     JSModuleDef *m;
     m = JS_NewCModule(ctx, module_name, js_fib_init);
diff --git a/examples/meson.build b/examples/meson.build
index 08c9d87b6..dc7512032 100644
--- a/examples/meson.build
+++ b/examples/meson.build
@@ -3,9 +3,9 @@ shared_module(
   'fib.c',
 
   name_prefix: '',
-  gnu_symbol_visibility: 'default',
-  c_args: ['-DJS_SHARED_LIBRARY'],
-  dependencies: host_system == 'windows' ? qjs_dep : [],
+  gnu_symbol_visibility: 'hidden',
+  c_args: qjs_module_args,
+  dependencies: qjs_dep,
 )
 
 shared_module(
@@ -13,7 +13,7 @@ shared_module(
   'point.c',
 
   name_prefix: '',
-  gnu_symbol_visibility: 'default',
-  c_args: ['-DJS_SHARED_LIBRARY'],
-  dependencies: host_system == 'windows' ? qjs_dep : [],
+  gnu_symbol_visibility: 'hidden',
+  c_args: qjs_module_args,
+  dependencies: qjs_dep,
 )
diff --git a/examples/point.c b/examples/point.c
index a82df1519..baa06388c 100644
--- a/examples/point.c
+++ b/examples/point.c
@@ -21,9 +21,11 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
-#include "../quickjs.h"
+
 #include <math.h>
 
+#include <quickjs.h>
+
 #define countof(x) (sizeof(x) / sizeof((x)[0]))
 
 /* Point Class */
@@ -141,15 +143,7 @@ static int js_point_init(JSContext *ctx, JSModuleDef *m)
     return 0;
 }
 
-#ifndef JS_EXTERN
-#ifdef _WIN32
-#define JS_EXTERN __declspec(dllexport)
-#else
-#define JS_EXTERN
-#endif
-#endif
-
-JS_EXTERN JSModuleDef *js_init_module(JSContext *ctx, const char *module_name)
+JS_MODULE_EXTERN JSModuleDef *js_init_module(JSContext *ctx, const char *module_name)
 {
     JSModuleDef *m;
     m = JS_NewCModule(ctx, module_name, js_point_init);
diff --git a/meson.build b/meson.build
index cf79060bc..fa80447ec 100644
--- a/meson.build
+++ b/meson.build
@@ -5,7 +5,6 @@ project(
   default_options: [
     'c_std=gnu11,c11',
     'warning_level=3',
-    'default_library=static',
   ],
   license: 'MIT',
   license_files: 'LICENSE',
@@ -15,6 +14,8 @@ project(
 host_system = host_machine.system()
 cc = meson.get_compiler('c')
 
+add_project_arguments('-DQUICKJS_NG_BUILD', language: 'c')
+
 qjs_gcc_warning_args = [
   '-Wno-unsafe-buffer-usage',
   '-Wno-sign-conversion',
@@ -133,7 +134,6 @@ qjs_sys_deps += dependency('threads', required: false)
 qjs_sys_deps += dependency('dl', required: false)
 
 qjs_srcs = files(
-  'cutils.c',
   'dtoa.c',
   'libregexp.c',
   'libunicode.c',
@@ -149,6 +149,10 @@ qjs_libc_hdrs = files('quickjs-libc.h')
 
 if qjs_libc
   qjs_hdrs += qjs_libc_hdrs
+  add_project_arguments(
+    '-DQJS_BUILD_LIBC',
+    language: 'c'
+  )
 endif
 
 qjs_parser = get_option('parser')
@@ -163,29 +167,25 @@ if not qjs_parser
   qjs_c_args += ['-DQJS_DISABLE_PARSER']
 endif
 
-qjs_libc_lib = static_library(
-  'quickjs-libc',
-  qjs_libc_srcs,
+qjs_module_args = ['-DQUICKJS_NG_MODULE_BUILD']
+
+cutils_lib = static_library(
+  'cutils',
+  'cutils.c',
 
   dependencies: qjs_sys_deps,
-  c_args: qjs_c_args,
-  gnu_symbol_visibility: 'hidden',
+  c_args: qjs_c_args
 )
 
 qjs_lib = library(
   'qjs',
   qjs_srcs,
-
-  # export public headers
-  generator(
-    find_program('cp', 'xcopy'),
-    output: ['@PLAINNAME@'],
-    arguments: ['@INPUT@', '@OUTPUT@'],
-  ).process(qjs_hdrs),
+  qjs_libc ? qjs_libc_srcs : [],
 
   dependencies: qjs_sys_deps,
-  link_whole: qjs_libc ? qjs_libc_lib : [],
-  c_args: qjs_c_args,
+  link_with: cutils_lib,
+  c_args: [qjs_c_args, '-DQUICKJS_NG_QJS_INTERNAL'],
+  c_shared_args: ['-DQUICKJS_NG_DLL'],
   gnu_symbol_visibility: 'hidden',
 
   install: true,
@@ -196,13 +196,41 @@ qjs_export_variables = [
   f'have_parser=@qjs_parser@'
 ]
 
+# Be conservative here: only pass -DQUICKJS_NG_DLL iff default_library ==
+# 'shared', thus qjs is guarranteed to be a DLL. Not passing -DQUICKJS_NG_DLL if
+# qjs is a DLL is not harmful, but passing the definition for DLL qjs is desired.
+# Alternatively, if -DQUICKJS_NG_DLL is passed for static qjs, the consumers
+# will not compile.
+qjs_dep_args = get_option('default_library') == 'shared' ? ['-DQUICKJS_NG_DLL'] : []
+
 qjs_dep = declare_dependency(
+  compile_args: qjs_dep_args,
   link_with: qjs_lib,
   dependencies: qjs_sys_deps,
-  include_directories: qjs_lib.private_dir_include(),
+  include_directories: include_directories('.'),
   variables: qjs_export_variables,
 )
 
+
+if qjs_libc
+  qjs_libc_dep = declare_dependency(
+    dependencies: qjs_dep
+  )
+else
+  qjs_libc_lib = static_library(
+    'quickjs-libc',
+    qjs_libc_srcs,
+
+    c_args: qjs_c_args,
+    link_with: cutils_lib,
+    dependencies: [qjs_sys_deps, qjs_dep],
+    gnu_symbol_visibility: 'hidden',
+  )
+  qjs_libc_dep = declare_dependency(
+    link_with: qjs_libc_lib
+  )
+endif
+
 if host_system == 'emscripten'
   qjs_wasm_export_name = 'getQuickJs'
   executable(
@@ -274,9 +302,8 @@ qjsc_exe = executable(
   qjsc_srcs,
 
   c_args: qjs_c_args,
-  link_with: qjs_libc ? [] : qjs_libc_lib,
-  dependencies: qjs_dep,
-
+  link_with: [cutils_lib],
+  dependencies: [qjs_dep, qjs_libc_dep],
   install: true,
 )
 
@@ -300,8 +327,8 @@ qjs_exe = executable(
   qjs_exe_srcs,
 
   c_args: qjs_c_args,
-  link_with: qjs_libc ? [] : qjs_libc_lib,
-  dependencies: [qjs_dep, mimalloc_dep],
+  link_with: [cutils_lib],
+  dependencies: [qjs_dep, qjs_libc_dep, mimalloc_dep],
   export_dynamic: true,
 
   install: true,
@@ -328,7 +355,7 @@ if meson.is_cross_build()
     qjs_libc_srcs,
 
     dependencies: qjs_sys_native_deps,
-    c_args: qjs_c_args,
+    c_args: [qjs_c_args, '-DQUICKJS_NG_QJS_INTERNAL'],
     gnu_symbol_visibility: 'hidden',
 
     build_by_default: false,
@@ -381,10 +408,10 @@ if tests.allowed()
     run262_exe = executable(
       'run-test262',
       'run-test262.c',
-      qjs_libc_srcs,
 
+      link_with: cutils_lib,
       c_args: qjs_c_args,
-      dependencies: qjs_dep,
+      dependencies: [qjs_dep, qjs_libc_dep]
     )
 
     test(
@@ -484,6 +511,7 @@ if tests.allowed()
       'api-test',
       'api-test.c',
 
+      link_with: cutils_lib,
       c_args: qjs_c_args,
       dependencies: qjs_dep,
       build_by_default: false,
@@ -496,10 +524,9 @@ if tests.allowed()
     executable(
       'function_source',
       'gen/function_source.c',
-      qjs_libc_srcs,
 
       c_args: qjs_c_args,
-      dependencies: qjs_dep,
+      dependencies: [qjs_dep, qjs_libc_dep],
       build_by_default: false,
     ),
   )
@@ -508,9 +535,9 @@ endif
 # Unicode generator
 unicode_gen = executable(
   'unicode_gen',
-  'cutils.c',
   'unicode_gen.c',
 
+  link_with: cutils_lib,
   c_args: qjs_c_args,
   build_by_default: false,
 )
@@ -607,19 +634,17 @@ if examples.allowed()
   executable(
     'hello',
     'gen/hello.c',
-    qjs_libc_srcs,
 
     c_args: qjs_c_args,
-    dependencies: qjs_dep,
+    dependencies: [qjs_dep, qjs_libc_dep]
   )
 
   executable(
     'hello_module',
     'gen/hello_module.c',
-    qjs_libc_srcs,
 
     c_args: qjs_c_args,
-    dependencies: qjs_dep,
+    dependencies: [qjs_dep, qjs_libc_dep]
   )
 
   subdir('examples')
@@ -628,10 +653,9 @@ if examples.allowed()
     'test_fib',
     'examples/fib.c',
     'gen/test_fib.c',
-    qjs_libc_srcs,
 
-    c_args: qjs_c_args,
-    dependencies: qjs_dep,
+    c_args: [qjs_c_args, qjs_module_args],
+    dependencies: [qjs_dep, qjs_libc_dep],
     export_dynamic: true,
   )
 endif
diff --git a/quickjs-libc.h b/quickjs-libc.h
index 58c2525bc..06aae5b83 100644
--- a/quickjs-libc.h
+++ b/quickjs-libc.h
@@ -34,49 +34,41 @@
 extern "C" {
 #endif
 
-#if defined(__GNUC__) || defined(__clang__)
-#define JS_EXTERN __attribute__((visibility("default")))
-#else
-#define JS_EXTERN /* nothing */
-#endif
-
-JS_EXTERN JSModuleDef *js_init_module_std(JSContext *ctx,
+JS_LIBC_EXTERN JSModuleDef *js_init_module_std(JSContext *ctx,
                                           const char *module_name);
-JS_EXTERN JSModuleDef *js_init_module_os(JSContext *ctx,
+JS_LIBC_EXTERN JSModuleDef *js_init_module_os(JSContext *ctx,
                                          const char *module_name);
-JS_EXTERN JSModuleDef *js_init_module_bjson(JSContext *ctx,
+JS_LIBC_EXTERN JSModuleDef *js_init_module_bjson(JSContext *ctx,
                                             const char *module_name);
-JS_EXTERN void js_std_add_helpers(JSContext *ctx, int argc, char **argv);
-JS_EXTERN int js_std_loop(JSContext *ctx);
-JS_EXTERN JSValue js_std_await(JSContext *ctx, JSValue obj);
-JS_EXTERN void js_std_init_handlers(JSRuntime *rt);
-JS_EXTERN void js_std_free_handlers(JSRuntime *rt);
-JS_EXTERN void js_std_dump_error(JSContext *ctx);
-JS_EXTERN uint8_t *js_load_file(JSContext *ctx, size_t *pbuf_len,
+JS_LIBC_EXTERN void js_std_add_helpers(JSContext *ctx, int argc, char **argv);
+JS_LIBC_EXTERN int js_std_loop(JSContext *ctx);
+JS_LIBC_EXTERN JSValue js_std_await(JSContext *ctx, JSValue obj);
+JS_LIBC_EXTERN void js_std_init_handlers(JSRuntime *rt);
+JS_LIBC_EXTERN void js_std_free_handlers(JSRuntime *rt);
+JS_LIBC_EXTERN void js_std_dump_error(JSContext *ctx);
+JS_LIBC_EXTERN uint8_t *js_load_file(JSContext *ctx, size_t *pbuf_len,
                                 const char *filename);
-JS_EXTERN int js_module_set_import_meta(JSContext *ctx, JSValueConst func_val,
+JS_LIBC_EXTERN int js_module_set_import_meta(JSContext *ctx, JSValueConst func_val,
                                         bool use_realpath, bool is_main);
-JS_EXTERN JSModuleDef *js_module_loader(JSContext *ctx,
+JS_LIBC_EXTERN JSModuleDef *js_module_loader(JSContext *ctx,
                                         const char *module_name, void *opaque,
                                         JSValueConst attributes);
-JS_EXTERN int js_module_check_attributes(JSContext *ctx, void *opaque,
+JS_LIBC_EXTERN int js_module_check_attributes(JSContext *ctx, void *opaque,
                                          JSValueConst attributes);
-JS_EXTERN int js_module_test_json(JSContext *ctx, JSValueConst attributes);
-JS_EXTERN void js_std_eval_binary(JSContext *ctx, const uint8_t *buf,
+JS_LIBC_EXTERN int js_module_test_json(JSContext *ctx, JSValueConst attributes);
+JS_LIBC_EXTERN void js_std_eval_binary(JSContext *ctx, const uint8_t *buf,
                                   size_t buf_len, int flags);
-JS_EXTERN void js_std_promise_rejection_tracker(JSContext *ctx,
+JS_LIBC_EXTERN void js_std_promise_rejection_tracker(JSContext *ctx,
                                                 JSValueConst promise,
                                                 JSValueConst reason,
                                                 bool is_handled,
                                                 void *opaque);
 // Defaults to JS_NewRuntime, no-op if compiled without worker support.
 // Call before creating the first worker thread.
-JS_EXTERN void js_std_set_worker_new_runtime_func(JSRuntime *(*func)(void));
+JS_LIBC_EXTERN void js_std_set_worker_new_runtime_func(JSRuntime *(*func)(void));
 // Defaults to JS_NewContext, no-op if compiled without worker support.
 // Call before creating the first worker thread.
-JS_EXTERN void js_std_set_worker_new_context_func(JSContext *(*func)(JSRuntime *rt));
-
-#undef JS_EXTERN
+JS_LIBC_EXTERN void js_std_set_worker_new_context_func(JSContext *(*func)(JSRuntime *rt));
 
 #ifdef __cplusplus
 } /* extern "C" { */
diff --git a/quickjs.h b/quickjs.h
index d66051324..2dd41e42b 100644
--- a/quickjs.h
+++ b/quickjs.h
@@ -39,14 +39,104 @@ extern "C" {
 
 #define QUICKJS_NG 1
 
+/* Helpers. */
+#if defined(_WIN32) || defined(__CYGWIN__)
+# define QUICKJS_NG_PLAT_WIN32 1
+#endif /* defined(_WIN32) || defined(__CYGWIN__) */
+
 #if defined(__GNUC__) || defined(__clang__)
-#define js_force_inline       inline __attribute__((always_inline))
-#define JS_EXTERN __attribute__((visibility("default")))
+# define QUICKJS_NG_CC_GNULIKE 1
+#endif /* defined(__GNUC__) || defined(__clang__) */
+
+/*
+ * `js_force_inline` -- helper macro forcing the inlining of a function.
+ */
+#ifdef QUICKJS_NG_PLAT_WIN32
+# ifdef QUICKJS_NG_CC_GNULIKE
+#  define js_force_inline inline __attribute__((always_inline))
+# else
+#  define js_force_inline __forceinline
+# endif
+#else
+# ifdef QUICKJS_NG_CC_GNULIKE
+#  define js_force_inline inline __attribute__((always_inline))
+# else
+#  define js_force_inline inline
+# endif
+#endif /* QUICKJS_NG_PLAT_WIN32 */
+
+/*
+ * `JS_EXTERN` -- helper macro that must be used to mark the external
+ * interfaces of libqjs.
+ *
+ * Explicitly undefine the macro first in case a previous header included this.
+ * This is done in order to avoid the redefinition warnings/errors upon a
+ * different definition of `JS_EXTERN`.
+ *
+ * Windows note: The `__declspec` syntax is supported by both Clang and GCC.
+ * The QUICKJS_NG_QJS_INTERNAL macro must be defined for libqjs (and only for
+ * it) to properly export symbols.
+ */
+#ifdef QUICKJS_NG_PLAT_WIN32
+/* Define QUICKJS_NG_DLL if building or using shared qjs. */
+# ifdef QUICKJS_NG_DLL
+#  ifdef QUICKJS_NG_QJS_INTERNAL
+#   define JS_EXTERN __declspec(dllexport)
+#  else
+#    define JS_EXTERN __declspec(dllimport)
+#  endif
+# else
+#  define JS_EXTERN /* nothing */
+# endif
+#else
+# ifdef QUICKJS_NG_CC_GNULIKE
+#  define JS_EXTERN __attribute__((visibility("default")))
+# else
+#  define JS_EXTERN /* nothing */
+# endif
+#endif /* QUICKJS_NG_PLAT_WIN32 */
+
+/*
+ * `JS_LIBC_EXTERN` -- helper macro that must be used to mark the extern
+ * interfaces of quickjs-libc specifically.
+ */
+#if defined(QUICKJS_NG_BUILD) && !defined(QJS_BUILD_LIBC) && defined(QUICKJS_NG_PLAT_WIN32)
+/*
+ * We are building QuickJS-NG, quickjs-libc is a static library and we are on
+ * Windows. Then, make sure to not export any interfaces.
+ */
+# define JS_LIBC_EXTERN /* nothing */
 #else
-#define js_force_inline  inline
-#define JS_EXTERN /* nothing */
+/*
+ * Otherwise, if we are either (1) not building QuickJS-NG, (2) libc is built as
+ * a part of libqjs, or (3) we are not on Windows, define JS_LIBC_EXTERN to
+ * JS_EXTERN.
+ */
+# define JS_LIBC_EXTERN JS_EXTERN
 #endif
 
+/*
+ * `JS_MODULE_EXTERN` -- helper macro that must be used to mark `js_init_module`
+ * and other public functions of the binary modules. See examples/ for examples
+ * of the usage.
+ *
+ * Windows note: -DQUICKJS_NG_MODULE_BUILD must be set when building a binary
+ * module to properly set __declspec.
+ */
+#ifdef QUICKJS_NG_PLAT_WIN32
+# ifdef QUICKJS_NG_MODULE_BUILD
+#  define JS_MODULE_EXTERN __declspec(dllexport)
+# else
+#  define JS_MODULE_EXTERN __declspec(dllimport)
+# endif
+#else
+# ifdef QUICKJS_NG_CC_GNULIKE
+#  define JS_MODULE_EXTERN __attribute__((visibility("default")))
+# else
+#  define JS_MODULE_EXTERN /* nothing */
+# endif
+#endif /* QUICKJS_NG_PLAT_WIN32 */
+
 /* Borrowed from Folly */
 #ifndef JS_PRINTF_FORMAT
 #ifdef _MSC_VER
@@ -65,6 +155,9 @@ extern "C" {
 #endif
 #endif
 
+#undef QUICKJS_NG_CC_GNULIKE
+#undef QUICKJS_NG_PLAT_WIN32
+
 typedef struct JSRuntime JSRuntime;
 typedef struct JSContext JSContext;
 typedef struct JSObject JSObject;
@@ -1325,7 +1418,6 @@ JS_EXTERN const char* JS_GetVersion(void);
 /* Integration point for quickjs-libc.c, not for public use. */
 JS_EXTERN uintptr_t js_std_cmd(int cmd, ...);
 
-#undef JS_EXTERN
 #undef js_force_inline
 
 #ifdef __cplusplus