diff --git a/lib/quickjs/quickjs.c b/lib/quickjs/quickjs.c
index af7ea852..427b36df 100644
--- a/lib/quickjs/quickjs.c
+++ b/lib/quickjs/quickjs.c
@@ -306,6 +306,7 @@ struct JSRuntime {
     uint32_t operator_count;
 #endif
     void *user_opaque;
+    JSRuntimeCleanUpFunc *user_cleanup;
 };
 
 struct JSClass {
@@ -1703,6 +1704,11 @@ void JS_SetRuntimeOpaque(JSRuntime *rt, void *opaque)
     rt->user_opaque = opaque;
 }
 
+void JS_SetRuntimeCleanUpFunc(JSRuntime *rt, JSRuntimeCleanUpFunc cleanup_func)
+{
+    rt->user_cleanup = cleanup_func;
+}
+
 /* default memory allocation functions with memory limitation */
 static size_t js_def_malloc_usable_size(const void *ptr)
 {
@@ -1960,6 +1966,8 @@ void JS_FreeRuntime(JSRuntime *rt)
 
     JS_RunGC(rt);
 
+    rt->user_cleanup(rt);
+
 #ifdef DUMP_LEAKS
     /* leaking objects */
     {
diff --git a/lib/quickjs/quickjs.h b/lib/quickjs/quickjs.h
index 8c81be47..366f341b 100644
--- a/lib/quickjs/quickjs.h
+++ b/lib/quickjs/quickjs.h
@@ -331,6 +331,8 @@ typedef struct JSMallocFunctions {
 
 typedef struct JSGCObjectHeader JSGCObjectHeader;
 
+typedef void JSRuntimeCleanUpFunc(JSRuntime *rt);
+
 JSRuntime *JS_NewRuntime(void);
 /* info lifetime must exceed that of rt */
 void JS_SetRuntimeInfo(JSRuntime *rt, const char *info);
@@ -345,6 +347,7 @@ JSRuntime *JS_NewRuntime2(const JSMallocFunctions *mf, void *opaque);
 void JS_FreeRuntime(JSRuntime *rt);
 void *JS_GetRuntimeOpaque(JSRuntime *rt);
 void JS_SetRuntimeOpaque(JSRuntime *rt, void *opaque);
+void JS_SetRuntimeCleanUpFunc(JSRuntime *rt, JSRuntimeCleanUpFunc cleanup_func);
 typedef void JS_MarkFunc(JSRuntime *rt, JSGCObjectHeader *gp);
 void JS_MarkValue(JSRuntime *rt, JSValueConst val, JS_MarkFunc *mark_func);
 void JS_RunGC(JSRuntime *rt);
diff --git a/src/bindings/quickjs.nim b/src/bindings/quickjs.nim
index 836bedac..20dd048b 100644
--- a/src/bindings/quickjs.nim
+++ b/src/bindings/quickjs.nim
@@ -132,6 +132,8 @@ type
   JSClassExoticMethodsConst* {.importc: "const JSClassExoticMethods *",
     header: qjsheader.} = ptr JSClassExoticMethods
 
+  JSRuntimeCleanUpFunc* {.importc.} = proc(rt: JSRuntime) {.cdecl.}
+
   JSClassDef* {.importc, header: qjsheader.} = object
     class_name*: cstring
     finalizer*: JSClassFinalizer
@@ -555,6 +557,8 @@ proc JS_ExecutePendingJob*(rt: JSRuntime; pctx: ptr JSContext): cint
 
 proc JS_GetRuntimeOpaque*(rt: JSRuntime): pointer
 proc JS_SetRuntimeOpaque*(rt: JSRuntime; p: pointer)
+proc JS_SetRuntimeCleanUpFunc*(rt: JSRuntime;
+  cleanup_func: JSRuntimeCleanUpFunc)
 
 proc JS_SetContextOpaque*(ctx: JSContext; opaque: pointer)
 proc JS_GetContextOpaque*(ctx: JSContext): pointer
diff --git a/src/js/javascript.nim b/src/js/javascript.nim
index e2e91a4f..39330361 100644
--- a/src/js/javascript.nim
+++ b/src/js/javascript.nim
@@ -121,6 +121,27 @@ proc bindRealloc(s: ptr JSMallocState; p: pointer; size: csize_t): pointer
     {.cdecl.} =
   return realloc(p, size)
 
+proc jsRuntimeCleanUp(rt: JSRuntime) {.cdecl.} =
+  let rtOpaque = rt.getOpaque()
+  GC_unref(rtOpaque)
+  assert rtOpaque.destroying == nil
+  var ps: seq[pointer] = @[]
+  for p in rtOpaque.plist.values:
+    ps.add(p)
+  rtOpaque.plist.clear()
+  var unrefs: seq[proc() {.closure.}] = @[]
+  for (_, unref) in rtOpaque.refmap.values:
+    unrefs.add(unref)
+  rtOpaque.refmap.clear()
+  for unref in unrefs:
+    unref()
+  for p in ps:
+    #TODO maybe finalize?
+    let val = JS_MKPTR(JS_TAG_OBJECT, p)
+    JS_SetOpaque(val, nil)
+    JS_FreeValueRT(rt, val)
+  JS_RunGC(rt)
+
 proc newJSRuntime*(): JSRuntime =
   var mf {.global.} = JSMallocFunctions(
     js_malloc: bindMalloc,
@@ -132,6 +153,7 @@ proc newJSRuntime*(): JSRuntime =
   let opaque = JSRuntimeOpaque()
   GC_ref(opaque)
   JS_SetRuntimeOpaque(rt, cast[pointer](opaque))
+  JS_SetRuntimeCleanUpFunc(rt, jsRuntimeCleanUp)
   # Must be added after opaque is set, or there is a chance of
   # nim_finalize_for_js dereferencing it (at the new call).
   runtimes.add(rt)
@@ -170,17 +192,6 @@ proc free*(ctx: JSContext) =
   JS_FreeContext(ctx)
 
 proc free*(rt: JSRuntime) =
-  let opaque = rt.getOpaque()
-  GC_unref(opaque)
-  var ps: seq[pointer] = @[]
-  for p in opaque.plist.values:
-    ps.add(p)
-  opaque.plist.clear()
-  for p in ps:
-    #TODO maybe finalize?
-    let val = JS_MKPTR(JS_TAG_OBJECT, p)
-    JS_SetOpaque(val, nil)
-    JS_FreeValueRT(rt, val)
   JS_FreeRuntime(rt)
   runtimes.del(runtimes.find(rt))
 
@@ -1503,8 +1514,8 @@ proc bindGetSet(stmts: NimNode; info: RegistryInfo) =
         JS_CGETSET_DEF_NOCONF(`k`, `get`, `set`))
 
 proc bindExtraGetSet(stmts: NimNode; info: var RegistryInfo;
-    extra_getset: openArray[TabGetSet]) =
-  for x in extra_getset:
+    extraGetSet: openArray[TabGetSet]) =
+  for x in extraGetSet:
     let k = x.name
     let g = x.get
     let s = x.set
@@ -1604,8 +1615,8 @@ proc bindEndStmts(endstmts: NimNode; info: RegistryInfo) =
 macro registerType*(ctx: JSContext; t: typed; parent: JSClassID = 0;
     asglobal: static bool = false; globalparent: static bool = false;
     nointerface = false; name: static string = "";
-    has_extra_getset: static bool = false;
-    extra_getset: static openArray[TabGetSet] = []; namespace = JS_NULL;
+    hasExtraGetSet: static bool = false;
+    extraGetSet: static openArray[TabGetSet] = []; namespace = JS_NULL;
     errid = opt(JSErrorEnum); ishtmldda = false): JSClassID =
   var stmts = newStmtList()
   var info = newRegistryInfo(t, name)
@@ -1622,11 +1633,11 @@ macro registerType*(ctx: JSContext; t: typed; parent: JSClassID = 0;
   stmts.registerSetters(info, pragmas.jsset)
   stmts.bindFunctions(info)
   stmts.bindGetSet(info)
-  if has_extra_getset:
-    #HACK: for some reason, extra_getset gets weird contents when nothing is
+  if hasExtraGetSet:
+    #HACK: for some reason, extraGetSet gets weird contents when nothing is
     # passed to it. So we need an extra flag to signal if anything has
     # been passed to it at all.
-    stmts.bindExtraGetSet(info, extra_getset)
+    stmts.bindExtraGetSet(info, extraGetSet)
   let sctr = stmts.bindConstructor(info)
   if not asglobal:
     stmts.bindCheckDestroy(info)