diff --git a/packages/babel-helpers/src/helpers-generated.ts b/packages/babel-helpers/src/helpers-generated.ts
index b0006a32171d..0d92c3f65de6 100644
--- a/packages/babel-helpers/src/helpers-generated.ts
+++ b/packages/babel-helpers/src/helpers-generated.ts
@@ -15,7 +15,7 @@ function helper(minVersion, source) {
 export default Object.freeze({
   applyDecs: helper(
     "7.17.0",
-    'function createMetadataMethodsForProperty(metadataMap,kind,property){return{getMetadata:function(key){if("symbol"!=typeof key)throw new TypeError("Metadata keys must be symbols, received: "+key);var metadataForKey=metadataMap[key];if(void 0!==metadataForKey)if(1===kind){var pub=metadataForKey.public;if(void 0!==pub)return pub[property]}else if(2===kind){var priv=metadataForKey.private;if(void 0!==priv)return priv.get(property)}else if(Object.hasOwnProperty.call(metadataForKey,"constructor"))return metadataForKey.constructor},setMetadata:function(key,value){if("symbol"!=typeof key)throw new TypeError("Metadata keys must be symbols, received: "+key);var metadataForKey=metadataMap[key];if(void 0===metadataForKey&&(metadataForKey=metadataMap[key]={}),1===kind){var pub=metadataForKey.public;void 0===pub&&(pub=metadataForKey.public={}),pub[property]=value}else if(2===kind){var priv=metadataForKey.priv;void 0===priv&&(priv=metadataForKey.private=new Map),priv.set(property,value)}else metadataForKey.constructor=value}}}function convertMetadataMapToFinal(obj,metadataMap){var parentMetadataMap=obj[Symbol.metadata||Symbol.for("Symbol.metadata")],metadataKeys=Object.getOwnPropertySymbols(metadataMap);if(0!==metadataKeys.length){for(var i=0;i<metadataKeys.length;i++){var key=metadataKeys[i],metaForKey=metadataMap[key],parentMetaForKey=parentMetadataMap?parentMetadataMap[key]:null,pub=metaForKey.public,parentPub=parentMetaForKey?parentMetaForKey.public:null;pub&&parentPub&&Object.setPrototypeOf(pub,parentPub);var priv=metaForKey.private;if(priv){var privArr=Array.from(priv.values()),parentPriv=parentMetaForKey?parentMetaForKey.private:null;parentPriv&&(privArr=privArr.concat(parentPriv)),metaForKey.private=privArr}parentMetaForKey&&Object.setPrototypeOf(metaForKey,parentMetaForKey)}parentMetadataMap&&Object.setPrototypeOf(metadataMap,parentMetadataMap),obj[Symbol.metadata||Symbol.for("Symbol.metadata")]=metadataMap}}function createAddInitializerMethod(initializers){return function(initializer){assertCallable(initializer,"An initializer"),initializers.push(initializer)}}function memberDecCtx(name,desc,metadataMap,initializers,kind,isStatic,isPrivate){var kindStr;switch(kind){case 1:kindStr="accessor";break;case 2:kindStr="method";break;case 3:kindStr="getter";break;case 4:kindStr="setter";break;default:kindStr="field"}var metadataKind,metadataName,ctx={kind:kindStr,name:isPrivate?"#"+name:name,isStatic:isStatic,isPrivate:isPrivate};if(0!==kind&&(ctx.addInitializer=createAddInitializerMethod(initializers)),isPrivate){metadataKind=2,metadataName=Symbol(name);var access={};0===kind?(access.get=desc.get,access.set=desc.set):2===kind?access.get=function(){return desc.value}:(1!==kind&&3!==kind||(access.get=function(){return desc.get.call(this)}),1!==kind&&4!==kind||(access.set=function(v){desc.set.call(this,v)})),ctx.access=access}else metadataKind=1,metadataName=name;return Object.assign(ctx,createMetadataMethodsForProperty(metadataMap,metadataKind,metadataName))}function assertCallable(fn,hint){if("function"!=typeof fn)throw new TypeError(hint+" must be a function")}function assertValidReturnValue(kind,value){var type=typeof value;if(1===kind){if("object"!==type||null===value)throw new TypeError("accessor decorators must return an object with get, set, or initializer properties or void 0");void 0!==value.get&&assertCallable(value.get,"accessor.get"),void 0!==value.set&&assertCallable(value.set,"accessor.set"),void 0!==value.initialize&&assertCallable(value.initialize,"accessor.initialize")}else if("function"!==type){var hint;throw hint=0===kind?"field":10===kind?"class":"method",new TypeError(hint+" decorators must return a function or void 0")}}function applyMemberDec(ret,base,decInfo,name,kind,isStatic,isPrivate,metadataMap,initializers){var desc,initializer,value,decs=decInfo[0];isPrivate?desc=0===kind||1===kind?{get:decInfo[3],set:decInfo[4]}:3===kind?{get:decInfo[3]}:4===kind?{set:decInfo[3]}:{value:decInfo[3]}:0!==kind&&(desc=Object.getOwnPropertyDescriptor(base,name)),1===kind?value={get:desc.get,set:desc.set}:2===kind?value=desc.value:3===kind?value=desc.get:4===kind&&(value=desc.set);var newValue,get,set,ctx=memberDecCtx(name,desc,metadataMap,initializers,kind,isStatic,isPrivate);if("function"==typeof decs)void 0!==(newValue=decs(value,ctx))&&(assertValidReturnValue(kind,newValue),0===kind?initializer=newValue:1===kind?(initializer=newValue.initialize,get=newValue.get||value.get,set=newValue.set||value.set,value={get:get,set:set}):value=newValue);else for(var i=decs.length-1;i>=0;i--){var newInit;if(void 0!==(newValue=(0,decs[i])(value,ctx)))assertValidReturnValue(kind,newValue),0===kind?newInit=newValue:1===kind?(newInit=newValue.initialize,get=newValue.get||value.get,set=newValue.set||value.set,value={get:get,set:set}):value=newValue,void 0!==newInit&&(void 0===initializer?initializer=newInit:"function"==typeof initializer?initializer=[initializer,newInit]:initializer.push(newInit))}if(0===kind||1===kind){if(void 0===initializer)initializer=function(instance,init){return init};else if("function"!=typeof initializer){var ownInitializers=initializer;initializer=function(instance,init){for(var value=init,i=0;i<ownInitializers.length;i++)value=ownInitializers[i].call(instance,value);return value}}else{var originalInitializer=initializer;initializer=function(instance,init){return originalInitializer.call(instance,init)}}ret.push(initializer)}0!==kind&&(1===kind?(desc.get=value.get,desc.set=value.set):2===kind?desc.value=value:3===kind?desc.get=value:4===kind&&(desc.set=value),isPrivate?1===kind?(ret.push((function(instance,args){return value.get.call(instance,args)})),ret.push((function(instance,args){return value.set.call(instance,args)}))):2===kind?ret.push(value):ret.push((function(instance,args){return value.call(instance,args)})):Object.defineProperty(base,name,desc))}function applyMemberDecs(ret,Class,protoMetadataMap,staticMetadataMap,decInfos){for(var protoInitializers,staticInitializers,existingProtoNonFields=new Map,existingStaticNonFields=new Map,i=0;i<decInfos.length;i++){var decInfo=decInfos[i];if(Array.isArray(decInfo)){var base,metadataMap,initializers,kind=decInfo[1],name=decInfo[2],isPrivate=decInfo.length>3,isStatic=kind>=5;if(isStatic?(base=Class,metadataMap=staticMetadataMap,0!==(kind-=5)&&(initializers=staticInitializers=staticInitializers||[])):(base=Class.prototype,metadataMap=protoMetadataMap,0!==kind&&(initializers=protoInitializers=protoInitializers||[])),0!==kind&&!isPrivate){var existingNonFields=isStatic?existingStaticNonFields:existingProtoNonFields,existingKind=existingNonFields.get(name)||0;if(!0===existingKind||3===existingKind&&4!==kind||4===existingKind&&3!==kind)throw new Error("Attempted to decorate a public method/accessor that has the same name as a previously decorated public method/accessor. This is not currently supported by the decorators plugin. Property name was: "+name);!existingKind&&kind>2?existingNonFields.set(name,kind):existingNonFields.set(name,!0)}applyMemberDec(ret,base,decInfo,name,kind,isStatic,isPrivate,metadataMap,initializers)}}pushInitializers(ret,protoInitializers),pushInitializers(ret,staticInitializers)}function pushInitializers(ret,initializers){initializers&&(initializers.length>0?(initializers=initializers.slice(),ret.push((function(instance){for(var i=0;i<initializers.length;i++)initializers[i].call(instance);return instance}))):ret.push((function(instance){return instance})))}function applyClassDecs(ret,targetClass,metadataMap,classDecs){if(classDecs.length>0){for(var initializers=[],newClass=targetClass,name=targetClass.name,ctx=Object.assign({kind:"class",name:name,addInitializer:createAddInitializerMethod(initializers)},createMetadataMethodsForProperty(metadataMap,0,name)),i=classDecs.length-1;i>=0;i--){var nextNewClass=classDecs[i](newClass,ctx);void 0!==nextNewClass&&(assertValidReturnValue(10,nextNewClass),newClass=nextNewClass)}ret.push(newClass),initializers.length>0?ret.push((function(){for(var i=0;i<initializers.length;i++)initializers[i].call(newClass)})):ret.push((function(){}))}}export default function applyDecs(targetClass,memberDecs,classDecs){var ret=[],staticMetadataMap={},protoMetadataMap={};return applyMemberDecs(ret,targetClass,protoMetadataMap,staticMetadataMap,memberDecs),convertMetadataMapToFinal(targetClass.prototype,protoMetadataMap),applyClassDecs(ret,targetClass,staticMetadataMap,classDecs),convertMetadataMapToFinal(targetClass,staticMetadataMap),ret}',
+    'function createMetadataMethodsForProperty(metadataMap,kind,property,decorationState){return{getMetadata:function(key){if(decorationState.finished)throw new Error("attempted to call getMetadata after decoration was finished");if("symbol"!=typeof key)throw new TypeError("Metadata keys must be symbols, received: "+key);var metadataForKey=metadataMap[key];if(void 0!==metadataForKey)if(1===kind){var pub=metadataForKey.public;if(void 0!==pub)return pub[property]}else if(2===kind){var priv=metadataForKey.private;if(void 0!==priv)return priv.get(property)}else if(Object.hasOwnProperty.call(metadataForKey,"constructor"))return metadataForKey.constructor},setMetadata:function(key,value){if(decorationState.finished)throw new Error("attempted to call setMetadata after decoration was finished");if("symbol"!=typeof key)throw new TypeError("Metadata keys must be symbols, received: "+key);var metadataForKey=metadataMap[key];if(void 0===metadataForKey&&(metadataForKey=metadataMap[key]={}),1===kind){var pub=metadataForKey.public;void 0===pub&&(pub=metadataForKey.public={}),pub[property]=value}else if(2===kind){var priv=metadataForKey.priv;void 0===priv&&(priv=metadataForKey.private=new Map),priv.set(property,value)}else metadataForKey.constructor=value}}}function convertMetadataMapToFinal(obj,metadataMap){var parentMetadataMap=obj[Symbol.metadata||Symbol.for("Symbol.metadata")],metadataKeys=Object.getOwnPropertySymbols(metadataMap);if(0!==metadataKeys.length){for(var i=0;i<metadataKeys.length;i++){var key=metadataKeys[i],metaForKey=metadataMap[key],parentMetaForKey=parentMetadataMap?parentMetadataMap[key]:null,pub=metaForKey.public,parentPub=parentMetaForKey?parentMetaForKey.public:null;pub&&parentPub&&Object.setPrototypeOf(pub,parentPub);var priv=metaForKey.private;if(priv){var privArr=Array.from(priv.values()),parentPriv=parentMetaForKey?parentMetaForKey.private:null;parentPriv&&(privArr=privArr.concat(parentPriv)),metaForKey.private=privArr}parentMetaForKey&&Object.setPrototypeOf(metaForKey,parentMetaForKey)}parentMetadataMap&&Object.setPrototypeOf(metadataMap,parentMetadataMap),obj[Symbol.metadata||Symbol.for("Symbol.metadata")]=metadataMap}}function createAddInitializerMethod(initializers,decorationState){return function(initializer){if(decorationState.finished)throw new Error("attempted to call addInitializer after decoration was finished");assertCallable(initializer,"An initializer"),initializers.push(initializer)}}function memberDecCtx(name,desc,metadataMap,initializers,kind,isStatic,isPrivate,decorationState){var kindStr;switch(kind){case 1:kindStr="accessor";break;case 2:kindStr="method";break;case 3:kindStr="getter";break;case 4:kindStr="setter";break;default:kindStr="field"}var metadataKind,metadataName,ctx={kind:kindStr,name:isPrivate?"#"+name:name,isStatic:isStatic,isPrivate:isPrivate};if(0!==kind&&(ctx.addInitializer=createAddInitializerMethod(initializers,decorationState)),isPrivate){metadataKind=2,metadataName=Symbol(name);var access={};0===kind?(access.get=desc.get,access.set=desc.set):2===kind?access.get=function(){return desc.value}:(1!==kind&&3!==kind||(access.get=function(){return desc.get.call(this)}),1!==kind&&4!==kind||(access.set=function(v){desc.set.call(this,v)})),ctx.access=access}else metadataKind=1,metadataName=name;return Object.assign(ctx,createMetadataMethodsForProperty(metadataMap,metadataKind,metadataName,decorationState))}function assertCallable(fn,hint){if("function"!=typeof fn)throw new TypeError(hint+" must be a function")}function assertValidReturnValue(kind,value){var type=typeof value;if(1===kind){if("object"!==type||null===value)throw new TypeError("accessor decorators must return an object with get, set, or init properties or void 0");void 0!==value.get&&assertCallable(value.get,"accessor.get"),void 0!==value.set&&assertCallable(value.set,"accessor.set"),void 0!==value.init&&assertCallable(value.init,"accessor.init")}else if("function"!==type){var hint;throw hint=0===kind?"field":10===kind?"class":"method",new TypeError(hint+" decorators must return a function or void 0")}}function applyMemberDec(ret,base,decInfo,name,kind,isStatic,isPrivate,metadataMap,initializers){var desc,initializer,value,newValue,get,set,decorationState,ctx,decs=decInfo[0];if(isPrivate?desc=0===kind||1===kind?{get:decInfo[3],set:decInfo[4]}:3===kind?{get:decInfo[3]}:4===kind?{set:decInfo[3]}:{value:decInfo[3]}:0!==kind&&(desc=Object.getOwnPropertyDescriptor(base,name)),1===kind?value={get:desc.get,set:desc.set}:2===kind?value=desc.value:3===kind?value=desc.get:4===kind&&(value=desc.set),"function"==typeof decs)ctx=memberDecCtx(name,desc,metadataMap,initializers,kind,isStatic,isPrivate,decorationState={finished:!1}),newValue=decs(value,ctx),decorationState.finished=!0,void 0!==newValue&&(assertValidReturnValue(kind,newValue),0===kind?initializer=newValue:1===kind?(initializer=newValue.init,get=newValue.get||value.get,set=newValue.set||value.set,value={get:get,set:set}):value=newValue);else for(var i=decs.length-1;i>=0;i--){var newInit,dec=decs[i];if(ctx=memberDecCtx(name,desc,metadataMap,initializers,kind,isStatic,isPrivate,decorationState={finished:!1}),newValue=dec(value,ctx),decorationState.finished=!0,void 0!==newValue)assertValidReturnValue(kind,newValue),0===kind?newInit=newValue:1===kind?(newInit=newValue.init,get=newValue.get||value.get,set=newValue.set||value.set,value={get:get,set:set}):value=newValue,void 0!==newInit&&(void 0===initializer?initializer=newInit:"function"==typeof initializer?initializer=[initializer,newInit]:initializer.push(newInit))}if(0===kind||1===kind){if(void 0===initializer)initializer=function(instance,init){return init};else if("function"!=typeof initializer){var ownInitializers=initializer;initializer=function(instance,init){for(var value=init,i=0;i<ownInitializers.length;i++)value=ownInitializers[i].call(instance,value);return value}}else{var originalInitializer=initializer;initializer=function(instance,init){return originalInitializer.call(instance,init)}}ret.push(initializer)}0!==kind&&(1===kind?(desc.get=value.get,desc.set=value.set):2===kind?desc.value=value:3===kind?desc.get=value:4===kind&&(desc.set=value),isPrivate?1===kind?(ret.push((function(instance,args){return value.get.call(instance,args)})),ret.push((function(instance,args){return value.set.call(instance,args)}))):2===kind?ret.push(value):ret.push((function(instance,args){return value.call(instance,args)})):Object.defineProperty(base,name,desc))}function applyMemberDecs(ret,Class,protoMetadataMap,staticMetadataMap,decInfos){for(var protoInitializers,staticInitializers,existingProtoNonFields=new Map,existingStaticNonFields=new Map,i=0;i<decInfos.length;i++){var decInfo=decInfos[i];if(Array.isArray(decInfo)){var base,metadataMap,initializers,kind=decInfo[1],name=decInfo[2],isPrivate=decInfo.length>3,isStatic=kind>=5;if(isStatic?(base=Class,metadataMap=staticMetadataMap,0!==(kind-=5)&&(initializers=staticInitializers=staticInitializers||[])):(base=Class.prototype,metadataMap=protoMetadataMap,0!==kind&&(initializers=protoInitializers=protoInitializers||[])),0!==kind&&!isPrivate){var existingNonFields=isStatic?existingStaticNonFields:existingProtoNonFields,existingKind=existingNonFields.get(name)||0;if(!0===existingKind||3===existingKind&&4!==kind||4===existingKind&&3!==kind)throw new Error("Attempted to decorate a public method/accessor that has the same name as a previously decorated public method/accessor. This is not currently supported by the decorators plugin. Property name was: "+name);!existingKind&&kind>2?existingNonFields.set(name,kind):existingNonFields.set(name,!0)}applyMemberDec(ret,base,decInfo,name,kind,isStatic,isPrivate,metadataMap,initializers)}}pushInitializers(ret,protoInitializers),pushInitializers(ret,staticInitializers)}function pushInitializers(ret,initializers){initializers&&(initializers.length>0?(initializers=initializers.slice(),ret.push((function(instance){for(var i=0;i<initializers.length;i++)initializers[i].call(instance);return instance}))):ret.push((function(instance){return instance})))}function applyClassDecs(ret,targetClass,metadataMap,classDecs){if(classDecs.length>0){for(var initializers=[],newClass=targetClass,name=targetClass.name,i=classDecs.length-1;i>=0;i--){var decorationState={finished:!1},ctx=Object.assign({kind:"class",name:name,addInitializer:createAddInitializerMethod(initializers,decorationState)},createMetadataMethodsForProperty(metadataMap,0,name,decorationState)),nextNewClass=classDecs[i](newClass,ctx);void 0!==nextNewClass&&(assertValidReturnValue(10,nextNewClass),newClass=nextNewClass),decorationState.finished=!0}ret.push(newClass),initializers.length>0?ret.push((function(){for(var i=0;i<initializers.length;i++)initializers[i].call(newClass)})):ret.push((function(){}))}}export default function applyDecs(targetClass,memberDecs,classDecs){var ret=[],staticMetadataMap={},protoMetadataMap={};return applyMemberDecs(ret,targetClass,protoMetadataMap,staticMetadataMap,memberDecs),convertMetadataMapToFinal(targetClass.prototype,protoMetadataMap),applyClassDecs(ret,targetClass,staticMetadataMap,classDecs),convertMetadataMapToFinal(targetClass,staticMetadataMap),ret}',
   ),
   asyncIterator: helper(
     "7.15.9",
diff --git a/packages/babel-helpers/src/helpers/applyDecs.js b/packages/babel-helpers/src/helpers/applyDecs.js
index 376206d3844b..e352b8afcc3b 100644
--- a/packages/babel-helpers/src/helpers/applyDecs.js
+++ b/packages/babel-helpers/src/helpers/applyDecs.js
@@ -18,9 +18,20 @@
   CLASS = 10; // only used in assertValidReturnValue
 */
 
-function createMetadataMethodsForProperty(metadataMap, kind, property) {
+function createMetadataMethodsForProperty(
+  metadataMap,
+  kind,
+  property,
+  decorationState
+) {
   return {
     getMetadata: function (key) {
+      if (decorationState.finished) {
+        throw new Error(
+          "attempted to call getMetadata after decoration was finished"
+        );
+      }
+
       if (typeof key !== "symbol") {
         throw new TypeError("Metadata keys must be symbols, received: " + key);
       }
@@ -44,6 +55,12 @@ function createMetadataMethodsForProperty(metadataMap, kind, property) {
       }
     },
     setMetadata: function (key, value) {
+      if (decorationState.finished) {
+        throw new Error(
+          "attempted to call setMetadata after decoration was finished"
+        );
+      }
+
       if (typeof key !== "symbol") {
         throw new TypeError("Metadata keys must be symbols, received: " + key);
       }
@@ -120,8 +137,14 @@ function convertMetadataMapToFinal(obj, metadataMap) {
   obj[Symbol.metadata || Symbol.for("Symbol.metadata")] = metadataMap;
 }
 
-function createAddInitializerMethod(initializers) {
+function createAddInitializerMethod(initializers, decorationState) {
   return function addInitializer(initializer) {
+    if (decorationState.finished) {
+      throw new Error(
+        "attempted to call addInitializer after decoration was finished"
+      );
+    }
+
     assertCallable(initializer, "An initializer");
     initializers.push(initializer);
   };
@@ -134,7 +157,8 @@ function memberDecCtx(
   initializers,
   kind,
   isStatic,
-  isPrivate
+  isPrivate,
+  decorationState
 ) {
   var kindStr;
 
@@ -163,7 +187,10 @@ function memberDecCtx(
   };
 
   if (kind !== 0 /* FIELD */) {
-    ctx.addInitializer = createAddInitializerMethod(initializers);
+    ctx.addInitializer = createAddInitializerMethod(
+      initializers,
+      decorationState
+    );
   }
 
   var metadataKind, metadataName;
@@ -204,7 +231,12 @@ function memberDecCtx(
 
   return Object.assign(
     ctx,
-    createMetadataMethodsForProperty(metadataMap, metadataKind, metadataName)
+    createMetadataMethodsForProperty(
+      metadataMap,
+      metadataKind,
+      metadataName,
+      decorationState
+    )
   );
 }
 
@@ -220,7 +252,7 @@ function assertValidReturnValue(kind, value) {
   if (kind === 1 /* ACCESSOR */) {
     if (type !== "object" || value === null) {
       throw new TypeError(
-        "accessor decorators must return an object with get, set, or initializer properties or void 0"
+        "accessor decorators must return an object with get, set, or init properties or void 0"
       );
     }
     if (value.get !== undefined) {
@@ -229,8 +261,8 @@ function assertValidReturnValue(kind, value) {
     if (value.set !== undefined) {
       assertCallable(value.set, "accessor.set");
     }
-    if (value.initialize !== undefined) {
-      assertCallable(value.initialize, "accessor.initialize");
+    if (value.init !== undefined) {
+      assertCallable(value.init, "accessor.init");
     }
   } else if (type !== "function") {
     var hint;
@@ -296,28 +328,32 @@ function applyMemberDec(
     value = desc.set;
   }
 
-  var ctx = memberDecCtx(
-    name,
-    desc,
-    metadataMap,
-    initializers,
-    kind,
-    isStatic,
-    isPrivate
-  );
-
-  var newValue, get, set;
+  var newValue, get, set, decorationState, ctx;
 
   if (typeof decs === "function") {
+    decorationState = { finished: false };
+    ctx = memberDecCtx(
+      name,
+      desc,
+      metadataMap,
+      initializers,
+      kind,
+      isStatic,
+      isPrivate,
+      decorationState
+    );
+
     newValue = decs(value, ctx);
 
+    decorationState.finished = true;
+
     if (newValue !== void 0) {
       assertValidReturnValue(kind, newValue);
 
       if (kind === 0 /* FIELD */) {
         initializer = newValue;
       } else if (kind === 1 /* ACCESSOR */) {
-        initializer = newValue.initialize;
+        initializer = newValue.init;
 
         get = newValue.get || value.get;
         set = newValue.set || value.set;
@@ -330,9 +366,22 @@ function applyMemberDec(
   } else {
     for (var i = decs.length - 1; i >= 0; i--) {
       var dec = decs[i];
+      decorationState = { finished: false };
+      ctx = memberDecCtx(
+        name,
+        desc,
+        metadataMap,
+        initializers,
+        kind,
+        isStatic,
+        isPrivate,
+        decorationState
+      );
 
       newValue = dec(value, ctx);
 
+      decorationState.finished = true;
+
       if (newValue !== void 0) {
         assertValidReturnValue(kind, newValue);
         var newInit;
@@ -340,7 +389,7 @@ function applyMemberDec(
         if (kind === 0 /* FIELD */) {
           newInit = newValue;
         } else if (kind === 1 /* ACCESSOR */) {
-          newInit = newValue.initialize;
+          newInit = newValue.init;
 
           get = newValue.get || value.get;
           set = newValue.set || value.set;
@@ -537,23 +586,35 @@ function applyClassDecs(ret, targetClass, metadataMap, classDecs) {
   if (classDecs.length > 0) {
     var initializers = [];
     var newClass = targetClass;
-
     var name = targetClass.name;
-    var ctx = Object.assign(
-      {
-        kind: "class",
-        name: name,
-        addInitializer: createAddInitializerMethod(initializers),
-      },
-      createMetadataMethodsForProperty(metadataMap, 0 /* CONSTRUCTOR */, name)
-    );
 
     for (var i = classDecs.length - 1; i >= 0; i--) {
+      var decorationState = { finished: false };
+
+      var ctx = Object.assign(
+        {
+          kind: "class",
+          name: name,
+          addInitializer: createAddInitializerMethod(
+            initializers,
+            decorationState
+          ),
+        },
+        createMetadataMethodsForProperty(
+          metadataMap,
+          0 /* CONSTRUCTOR */,
+          name,
+          decorationState
+        )
+      );
+
       var nextNewClass = classDecs[i](newClass, ctx);
       if (nextNewClass !== undefined) {
         assertValidReturnValue(10 /* CLASS */, nextNewClass);
         newClass = nextNewClass;
       }
+
+      decorationState.finished = true;
     }
 
     ret.push(newClass);
diff --git a/packages/babel-plugin-proposal-decorators/src/transformer-2021-12.ts b/packages/babel-plugin-proposal-decorators/src/transformer-2021-12.ts
index 2f4676921163..8170b5a0ff12 100644
--- a/packages/babel-plugin-proposal-decorators/src/transformer-2021-12.ts
+++ b/packages/babel-plugin-proposal-decorators/src/transformer-2021-12.ts
@@ -311,11 +311,28 @@ function isDecoratorInfo(
   return "decorators" in info;
 }
 
+function filteredOrderedDecoratorInfo(
+  info: (DecoratorInfo | ComputedPropInfo)[],
+): DecoratorInfo[] {
+  const filtered = info.filter(isDecoratorInfo);
+
+  return [
+    ...filtered.filter(
+      el => el.isStatic && el.kind >= ACCESSOR && el.kind <= SETTER,
+    ),
+    ...filtered.filter(
+      el => !el.isStatic && el.kind >= ACCESSOR && el.kind <= SETTER,
+    ),
+    ...filtered.filter(el => el.isStatic && el.kind === FIELD),
+    ...filtered.filter(el => !el.isStatic && el.kind === FIELD),
+  ];
+}
+
 function generateDecorationExprs(
   info: (DecoratorInfo | ComputedPropInfo)[],
 ): t.ArrayExpression {
   return t.arrayExpression(
-    info.filter(isDecoratorInfo).map(el => {
+    filteredOrderedDecoratorInfo(info).map(el => {
       const decs =
         el.decorators.length > 1
           ? t.arrayExpression(el.decorators)
@@ -341,19 +358,19 @@ function generateDecorationExprs(
 function extractElementLocalAssignments(
   decorationInfo: (DecoratorInfo | ComputedPropInfo)[],
 ) {
-  const locals: t.Identifier[] = [];
+  const localIds: t.Identifier[] = [];
 
-  for (const el of decorationInfo) {
-    if ("locals" in el && el.locals) {
-      if (Array.isArray(el.locals)) {
-        locals.push(...el.locals);
-      } else {
-        locals.push(el.locals);
-      }
+  for (const el of filteredOrderedDecoratorInfo(decorationInfo)) {
+    const { locals } = el;
+
+    if (Array.isArray(locals)) {
+      localIds.push(...locals);
+    } else if (locals !== undefined) {
+      localIds.push(locals);
     }
   }
 
-  return locals;
+  return localIds;
 }
 
 function addCallAccessorsFor(
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/private/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/private/exec.js
index 7f57c355fafc..3abec2906a37 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/private/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/private/exec.js
@@ -12,7 +12,7 @@ function dec({ get, set }, context) {
       set.call(this, v + 1);
     },
 
-    initialize(v) {
+    init(v) {
       return v ? v : 1;
     }
   }
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/public/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/public/exec.js
index b2febe59b23a..9a4a201d815c 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/public/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/public/exec.js
@@ -12,7 +12,7 @@ function dec({ get, set }, context) {
       set.call(this, v + 1);
     },
 
-    initialize(v) {
+    init(v) {
       return v ? v : 1;
     }
   }
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/static-private/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/static-private/exec.js
index 8da351a43219..e3a5fb5df934 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/static-private/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/static-private/exec.js
@@ -12,7 +12,7 @@ function dec({ get, set }, context) {
       set.call(this, v + 1);
     },
 
-    initialize(v) {
+    init(v) {
       return v ? v : 1;
     }
   }
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/static-public/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/static-public/exec.js
index 38bc72041da3..19859f83fc5a 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/static-public/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-accessors--to-es2015/static-public/exec.js
@@ -12,7 +12,7 @@ function dec({ get, set }, context) {
       set.call(this, v + 1);
     },
 
-    initialize(v) {
+    init(v) {
       return v ? v : 1;
     }
   }
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys--to-es2015/method-and-field/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys--to-es2015/method-and-field/exec.js
index 8ac906f1823a..72e253d55578 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys--to-es2015/method-and-field/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys--to-es2015/method-and-field/exec.js
@@ -17,7 +17,7 @@ class Foo {
 expect(elements).toHaveLength(2);
 
 expect(elements[0].context.name).toBe("a");
-expect(elements[0].val).toBe(undefined);
+expect(elements[0].val()).toBe(1);
 
 expect(elements[1].context.name).toBe("a");
-expect(elements[1].val()).toBe(1);
+expect(elements[1].val).toBe(undefined);
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys--to-es2015/method-and-field/output.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys--to-es2015/method-and-field/output.js
index 704f0d4c5dd9..cf6cfd0d2c3d 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys--to-es2015/method-and-field/output.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys--to-es2015/method-and-field/output.js
@@ -13,4 +13,4 @@ class Foo {
 
 }
 
-[_init_a, _initProto] = babelHelpers.applyDecs(Foo, [[dec, 0, "a"], [dec, 2, "a"]], []);
+[_init_a, _initProto] = babelHelpers.applyDecs(Foo, [[dec, 2, "a"], [dec, 0, "a"]], []);
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys/method-and-field/output.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys/method-and-field/output.js
index 6c1bdff1940b..ec133be95e04 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys/method-and-field/output.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-duplicated-keys/method-and-field/output.js
@@ -4,7 +4,7 @@ const dec = () => {};
 
 class Foo {
   static {
-    [_init_a, _initProto] = babelHelpers.applyDecs(this, [[dec, 0, "a"], [dec, 2, "a"]], []);
+    [_init_a, _initProto] = babelHelpers.applyDecs(this, [[dec, 2, "a"], [dec, 0, "a"]], []);
   }
   a = (_initProto(this), _init_a(this, 123));
 
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-context-addInitializer/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-context-addInitializer/exec.js
new file mode 100644
index 000000000000..ae9f6e6b0641
--- /dev/null
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-context-addInitializer/exec.js
@@ -0,0 +1,14 @@
+let addInitializer;
+
+function decMethod(_, context) {
+  ({ addInitializer } = context);
+  addInitializer(() => null);
+}
+
+class C {
+  @decMethod m() {}
+}
+
+expect(() => {
+  addInitializer(() => null);
+}).toThrow('attempted to call addInitializer after decoration was finished')
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-context-get-metadata/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-context-get-metadata/exec.js
new file mode 100644
index 000000000000..ce3d127a07ad
--- /dev/null
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-context-get-metadata/exec.js
@@ -0,0 +1,15 @@
+let getMetadata;
+let metadataSymbol = Symbol();
+
+function decMethod(_, context) {
+  ({ getMetadata } = context);
+  getMetadata(metadataSymbol);
+}
+
+class C {
+  @decMethod m() {}
+}
+
+expect(() => {
+  getMetadata(metadataSymbol);
+}).toThrow('attempted to call getMetadata after decoration was finished')
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-context-set-metadata/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-context-set-metadata/exec.js
new file mode 100644
index 000000000000..f554a5970134
--- /dev/null
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-context-set-metadata/exec.js
@@ -0,0 +1,15 @@
+let setMetadata;
+let metadataSymbol = Symbol();
+
+function decMethod(_, context) {
+  ({ setMetadata } = context);
+  setMetadata(metadataSymbol, 'value');
+}
+
+class C {
+  @decMethod m() {}
+}
+
+expect(() => {
+  setMetadata(metadataSymbol, 'value');
+}).toThrow('attempted to call setMetadata after decoration was finished')
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-proto-context-addInitializer/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-proto-context-addInitializer/exec.js
deleted file mode 100644
index def1d6e45e95..000000000000
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-proto-context-addInitializer/exec.js
+++ /dev/null
@@ -1,21 +0,0 @@
-let addInitializer, i = 0;
-const logs = [];
-
-function decCallProtoAddInitializer() {
-  addInitializer(() => logs.push(i++));
-}
-
-function decMethod(_, context) {
-  ({ addInitializer } = context);
-  addInitializer(() => logs.push(i++));
-}
-
-@decCallProtoAddInitializer
-class C {
-  @decMethod m() {}
-  @decCallProtoAddInitializer static n() {}
-}
-
-new C;
-
-expect(logs).toEqual([0, 1]);
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-static-context-addInitializer/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-static-context-addInitializer/exec.js
deleted file mode 100644
index 1a0d7aff9e6d..000000000000
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc--to-es2015/leaked-static-context-addInitializer/exec.js
+++ /dev/null
@@ -1,21 +0,0 @@
-let addInitializer, i = 0;
-const logs = [];
-
-function decCallStaticAddInitializer() {
-  addInitializer(() => logs.push(i++));
-}
-
-function decStaticMethod(_, context) {
-  ({ addInitializer } = context);
-  addInitializer(() => logs.push(i++));
-}
-
-@decCallStaticAddInitializer
-class C {
-  @decStaticMethod static m() {}
-  @decCallStaticAddInitializer n() {}
-}
-
-new C;
-
-expect(logs).toEqual([0, 1]);
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc/all-decorators/output.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc/all-decorators/output.js
index ab809be8665c..107c410c18ad 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc/all-decorators/output.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-misc/all-decorators/output.js
@@ -8,22 +8,22 @@ new class extends babelHelpers.identity {
   static {
     class Class {
       static {
-        [_init_a, _init_d, _init_e, _call_f, _call_g, _call_g2, _init_h, _get_h, _set_h, _init_i, _init_m, _init_n, _call_o, _call_p, _call_q, _init_r, _get_r, _set_r, _initProto, _initStatic, _Class, _initClass] = babelHelpers.applyDecs(this, [[dec, 0, "a"], [dec, 2, "b"], [dec, 3, "c"], [dec, 4, "c"], [dec, 1, "d"], [dec, 0, "e", function () {
-          return this.#e;
+        [_init_m, _call_o, _call_p, _call_q, _init_r, _get_r, _set_r, _init_d, _call_f, _call_g, _call_g2, _init_h, _get_h, _set_h, _init_i, _init_n, _init_a, _init_e, _initProto, _initStatic, _Class, _initClass] = babelHelpers.applyDecs(this, [[dec, 7, "j"], [dec, 8, "k"], [dec, 9, "l"], [dec, 6, "m"], [dec, 7, "o", function () {}], [dec, 8, "p", function () {}], [dec, 9, "q", function (v) {}], [dec, 6, "r", function () {
+          return this.#D;
         }, function (value) {
-          this.#e = value;
-        }], [dec, 2, "f", function () {}], [dec, 3, "g", function () {}], [dec, 4, "g", function (v) {}], [dec, 1, "h", function () {
+          this.#D = value;
+        }], [dec, 2, "b"], [dec, 3, "c"], [dec, 4, "c"], [dec, 1, "d"], [dec, 2, "f", function () {}], [dec, 3, "g", function () {}], [dec, 4, "g", function (v) {}], [dec, 1, "h", function () {
           return this.#B;
         }, function (value) {
           this.#B = value;
-        }], [dec, 5, "i"], [dec, 7, "j"], [dec, 8, "k"], [dec, 9, "l"], [dec, 6, "m"], [dec, 5, "n", function () {
+        }], [dec, 5, "i"], [dec, 5, "n", function () {
           return this.#n;
         }, function (value) {
           this.#n = value;
-        }], [dec, 7, "o", function () {}], [dec, 8, "p", function () {}], [dec, 9, "q", function (v) {}], [dec, 6, "r", function () {
-          return this.#D;
+        }], [dec, 0, "a"], [dec, 0, "e", function () {
+          return this.#e;
         }, function (value) {
-          this.#D = value;
+          this.#e = value;
         }]], [dec]);
 
         _initStatic(this);
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/accessor-initializers/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/accessor-initializers/exec.js
index 7d63f7f32353..892ced55301d 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/accessor-initializers/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/accessor-initializers/exec.js
@@ -17,7 +17,7 @@ function logAccessorDecoratorRun(a, b, c, d) {
     push(b);
     addInitializer(function () { push(c); });
     return {
-      initialize: () => push(d)
+      init: () => push(d)
     };
   };
 }
@@ -25,22 +25,24 @@ function logAccessorDecoratorRun(a, b, c, d) {
 @logClassDecoratorRun(0, 19, 29)
 @logClassDecoratorRun(1, 18, 28)
 class A {
-  @logAccessorDecoratorRun(2, 11)
-  @logAccessorDecoratorRun(3, 10)
+  @logAccessorDecoratorRun(2, 15, 31, 35)
+  @logAccessorDecoratorRun(3, 14, 30, 34)
   accessor a;
 
-  @logAccessorDecoratorRun(4, 13, 21, 25)
-  @logAccessorDecoratorRun(5, 12, 20, 24)
+  @logAccessorDecoratorRun(4, 11, 21, 25)
+  @logAccessorDecoratorRun(5, 10, 20, 24)
   static accessor b;
 
-  @logAccessorDecoratorRun(6, 15, 23, 27)
-  @logAccessorDecoratorRun(7, 14, 22, 26)
+  @logAccessorDecoratorRun(6, 13, 23, 27)
+  @logAccessorDecoratorRun(7, 12, 22, 26)
   static accessor #c;
 
-  @logAccessorDecoratorRun(8, 17)
-  @logAccessorDecoratorRun(9, 16)
+  @logAccessorDecoratorRun(8, 17, 33, 37)
+  @logAccessorDecoratorRun(9, 16, 32, 36)
   accessor #d;
 }
 
-var nums = Array.from({ length: 30 }, (_, i) => i);
+new A();
+
+var nums = Array.from({ length: 38 }, (_, i) => i);
 expect(log).toEqual(nums);
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/decorators/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/decorators/exec.js
index 795f3a9101dd..f44656aaee7c 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/decorators/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/decorators/exec.js
@@ -10,16 +10,16 @@ function logDecoratorRun(a, b) {
 @logDecoratorRun(0, 19)
 @logDecoratorRun(1, 18)
 class A {
-  @logDecoratorRun(2, 11)
-  @logDecoratorRun(3, 10)
+  @logDecoratorRun(2, 15)
+  @logDecoratorRun(3, 14)
   a;
 
-  @logDecoratorRun(4, 13)
-  @logDecoratorRun(5, 12)
+  @logDecoratorRun(4, 11)
+  @logDecoratorRun(5, 10)
   static b;
 
-  @logDecoratorRun(6, 15)
-  @logDecoratorRun(7, 14)
+  @logDecoratorRun(6, 13)
+  @logDecoratorRun(7, 12)
   static #c;
 
   @logDecoratorRun(8, 17)
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/initializers/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/initializers/exec.js
index 0adac4dc6c94..35e07dd009a1 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/initializers/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering--to-es2015/initializers/exec.js
@@ -14,38 +14,40 @@ function logDecoratorRun(a, b, c) {
 @logDecoratorRun(0, 35, 45)
 @logDecoratorRun(1, 34, 44)
 class A {
-  @logDecoratorRun(2, 19)
-  @logDecoratorRun(3, 18)
+  @logDecoratorRun(2, 27, 47)
+  @logDecoratorRun(3, 26, 46)
   a() {};
 
-  @logDecoratorRun(4, 21, 37)
-  @logDecoratorRun(5, 20, 36)
+  @logDecoratorRun(4, 19, 37)
+  @logDecoratorRun(5, 18, 36)
   static b() {};
 
-  @logDecoratorRun(6, 23, 39)
-  @logDecoratorRun(7, 22, 38)
+  @logDecoratorRun(6, 21, 39)
+  @logDecoratorRun(7, 20, 38)
   static #c() {};
 
-  @logDecoratorRun(8, 25)
-  @logDecoratorRun(9, 24)
+  @logDecoratorRun(8, 29, 49)
+  @logDecoratorRun(9, 28, 48)
   #d() {};
 
-  @logDecoratorRun(10, 27)
-  @logDecoratorRun(11, 26)
+  @logDecoratorRun(10, 31, 51)
+  @logDecoratorRun(11, 30, 50)
   accessor e;
 
-  @logDecoratorRun(12, 29, 41)
-  @logDecoratorRun(13, 28, 40)
+  @logDecoratorRun(12, 23, 41)
+  @logDecoratorRun(13, 22, 40)
   static accessor f;
 
-  @logDecoratorRun(14, 31, 43)
-  @logDecoratorRun(15, 30, 42)
+  @logDecoratorRun(14, 25, 43)
+  @logDecoratorRun(15, 24, 42)
   static accessor #g;
 
-  @logDecoratorRun(16, 33)
-  @logDecoratorRun(17, 32)
+  @logDecoratorRun(16, 33, 53)
+  @logDecoratorRun(17, 32, 52)
   accessor #h;
 }
 
-var nums = Array.from({ length: 46 }, (_, i) => i);
+new A();
+
+var nums = Array.from({ length: 54 }, (_, i) => i);
 expect(log).toEqual(nums);
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/accessor-initializers/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/accessor-initializers/exec.js
new file mode 100644
index 000000000000..892ced55301d
--- /dev/null
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/accessor-initializers/exec.js
@@ -0,0 +1,48 @@
+var log = [];
+
+function push(x) { log.push(x); return x; }
+
+function logClassDecoratorRun(a, b, c) {
+  push(a);
+  return function (el, { addInitializer }) {
+    push(b);
+    addInitializer(function () { push(c); });
+    return el;
+  };
+}
+
+function logAccessorDecoratorRun(a, b, c, d) {
+  push(a);
+  return function (el, { addInitializer }) {
+    push(b);
+    addInitializer(function () { push(c); });
+    return {
+      init: () => push(d)
+    };
+  };
+}
+
+@logClassDecoratorRun(0, 19, 29)
+@logClassDecoratorRun(1, 18, 28)
+class A {
+  @logAccessorDecoratorRun(2, 15, 31, 35)
+  @logAccessorDecoratorRun(3, 14, 30, 34)
+  accessor a;
+
+  @logAccessorDecoratorRun(4, 11, 21, 25)
+  @logAccessorDecoratorRun(5, 10, 20, 24)
+  static accessor b;
+
+  @logAccessorDecoratorRun(6, 13, 23, 27)
+  @logAccessorDecoratorRun(7, 12, 22, 26)
+  static accessor #c;
+
+  @logAccessorDecoratorRun(8, 17, 33, 37)
+  @logAccessorDecoratorRun(9, 16, 32, 36)
+  accessor #d;
+}
+
+new A();
+
+var nums = Array.from({ length: 38 }, (_, i) => i);
+expect(log).toEqual(nums);
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/decorators/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/decorators/exec.js
index b241220635c7..7a51e8b93b7e 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/decorators/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/decorators/exec.js
@@ -10,16 +10,16 @@ function logDecoratorRun(a, b) {
 @logDecoratorRun(0, 21)
 @logDecoratorRun(1, 20)
 class A {
-  @logDecoratorRun(2, 13)
-  @logDecoratorRun(3, 12)
+  @logDecoratorRun(2, 17)
+  @logDecoratorRun(3, 16)
   [push(4)];
 
-  @logDecoratorRun(5, 15)
-  @logDecoratorRun(6, 14)
+  @logDecoratorRun(5, 13)
+  @logDecoratorRun(6, 12)
   static [push(7)];
 
-  @logDecoratorRun(8, 17)
-  @logDecoratorRun(9, 16)
+  @logDecoratorRun(8, 15)
+  @logDecoratorRun(9, 14)
   static #c;
 
   @logDecoratorRun(10, 19)
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/initializers/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/initializers/exec.js
index 0adac4dc6c94..35e07dd009a1 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/initializers/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-ordering/initializers/exec.js
@@ -14,38 +14,40 @@ function logDecoratorRun(a, b, c) {
 @logDecoratorRun(0, 35, 45)
 @logDecoratorRun(1, 34, 44)
 class A {
-  @logDecoratorRun(2, 19)
-  @logDecoratorRun(3, 18)
+  @logDecoratorRun(2, 27, 47)
+  @logDecoratorRun(3, 26, 46)
   a() {};
 
-  @logDecoratorRun(4, 21, 37)
-  @logDecoratorRun(5, 20, 36)
+  @logDecoratorRun(4, 19, 37)
+  @logDecoratorRun(5, 18, 36)
   static b() {};
 
-  @logDecoratorRun(6, 23, 39)
-  @logDecoratorRun(7, 22, 38)
+  @logDecoratorRun(6, 21, 39)
+  @logDecoratorRun(7, 20, 38)
   static #c() {};
 
-  @logDecoratorRun(8, 25)
-  @logDecoratorRun(9, 24)
+  @logDecoratorRun(8, 29, 49)
+  @logDecoratorRun(9, 28, 48)
   #d() {};
 
-  @logDecoratorRun(10, 27)
-  @logDecoratorRun(11, 26)
+  @logDecoratorRun(10, 31, 51)
+  @logDecoratorRun(11, 30, 50)
   accessor e;
 
-  @logDecoratorRun(12, 29, 41)
-  @logDecoratorRun(13, 28, 40)
+  @logDecoratorRun(12, 23, 41)
+  @logDecoratorRun(13, 22, 40)
   static accessor f;
 
-  @logDecoratorRun(14, 31, 43)
-  @logDecoratorRun(15, 30, 42)
+  @logDecoratorRun(14, 25, 43)
+  @logDecoratorRun(15, 24, 42)
   static accessor #g;
 
-  @logDecoratorRun(16, 33)
-  @logDecoratorRun(17, 32)
+  @logDecoratorRun(16, 33, 53)
+  @logDecoratorRun(17, 32, 52)
   accessor #h;
 }
 
-var nums = Array.from({ length: 46 }, (_, i) => i);
+new A();
+
+var nums = Array.from({ length: 54 }, (_, i) => i);
 expect(log).toEqual(nums);
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-runtime-errors--to-es2015/invalid-accessor-decorator-return/exec.js b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-runtime-errors--to-es2015/invalid-accessor-decorator-return/exec.js
index 167c235d3de2..cd977fce13e0 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-runtime-errors--to-es2015/invalid-accessor-decorator-return/exec.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/2021-12-runtime-errors--to-es2015/invalid-accessor-decorator-return/exec.js
@@ -3,18 +3,18 @@ const returnsNull = () => null;
 const returnsFalse = () => false;
 const returnsFunction = () => () => {}
 const returnsGetSet = () => ({ set(v) {}, get() {} });
-const returnsInitialize = () => ({ initialize() {} });
+const returnsInit = () => ({ init() {} });
 const returnsGetFalse = () => ({ get: false });
 const returnsSetFalse = () => ({ set: false });
-const returnsInitializeFalse = () => ({ initialize: false });
+const returnsInitFalse = () => ({ init: false });
 
-expect(() => class { @returnsNull accessor a }).toThrow("accessor decorators must return an object with get, set, or initializer properties or void 0")
-expect(() => class { @returnsFalse accessor a }).toThrow("accessor decorators must return an object with get, set, or initializer properties or void 0")
-expect(() => class { @returnsFunction accessor a }).toThrow("accessor decorators must return an object with get, set, or initializer properties or void 0")
+expect(() => class { @returnsNull accessor a }).toThrow("accessor decorators must return an object with get, set, or init properties or void 0")
+expect(() => class { @returnsFalse accessor a }).toThrow("accessor decorators must return an object with get, set, or init properties or void 0")
+expect(() => class { @returnsFunction accessor a }).toThrow("accessor decorators must return an object with get, set, or init properties or void 0")
 expect(() => class { @returnsGetFalse accessor a }).toThrow("accessor.get must be a function");
 expect(() => class { @returnsSetFalse accessor a }).toThrow("accessor.set must be a function");
-expect(() => class { @returnsInitializeFalse accessor a }).toThrow("accessor.initialize must be a function");
+expect(() => class { @returnsInitFalse accessor a }).toThrow("accessor.init must be a function");
 
 expect(() => class { @returnsGetSet accessor a }).not.toThrow();
-expect(() => class { @returnsInitialize accessor a }).not.toThrow();
+expect(() => class { @returnsInit accessor a }).not.toThrow();
 expect(() => class { @returnsUndefined accessor a }).not.toThrow();