diff --git a/README.md b/README.md
index 6b40f1359b..1636728535 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@ like any other class.
 
 > NOTE: Due to performance of the hosted JavaScript engine and marshaling costs,
 __jsii__ modules are likely to be used for development and build tools, as
-oppose to performance-sensitive runtime behavior.
+opposed to performance-sensitive runtime behavior.
 
 From Java:
 
diff --git a/packages/jsii-calc-lib/lib/index.ts b/packages/jsii-calc-lib/lib/index.ts
index c1e1a616aa..295ab1ef7c 100644
--- a/packages/jsii-calc-lib/lib/index.ts
+++ b/packages/jsii-calc-lib/lib/index.ts
@@ -95,8 +95,8 @@ export interface StructWithOnlyOptionals {
  * See awslabs/jsii#138
  */
 export enum EnumFromScopedModule {
-    Value1,
-    Value2
+    VALUE1,
+    VALUE2
 }
 
 /**
diff --git a/packages/jsii-calc-lib/test/assembly.jsii b/packages/jsii-calc-lib/test/assembly.jsii
index 64ee0bcf09..99adf00bbe 100644
--- a/packages/jsii-calc-lib/test/assembly.jsii
+++ b/packages/jsii-calc-lib/test/assembly.jsii
@@ -136,13 +136,13 @@
           "docs": {
             "stability": "deprecated"
           },
-          "name": "Value1"
+          "name": "VALUE1"
         },
         {
           "docs": {
             "stability": "deprecated"
           },
-          "name": "Value2"
+          "name": "VALUE2"
         }
       ],
       "name": "EnumFromScopedModule"
@@ -540,5 +540,5 @@
     }
   },
   "version": "0.11.3",
-  "fingerprint": "jAkwT5aChzSZi3hTeylIFDPL1J8qUy++0B75C5vIA6Y="
+  "fingerprint": "iggTfEXzBxodU2TEDzkmrmsuEakOvA/UXmOA/8nQboU="
 }
diff --git a/packages/jsii-calc/lib/calculator.ts b/packages/jsii-calc/lib/calculator.ts
index 00730f1ac5..0e82f366c4 100644
--- a/packages/jsii-calc/lib/calculator.ts
+++ b/packages/jsii-calc/lib/calculator.ts
@@ -133,7 +133,7 @@ export namespace composition {
         /**
          * The .toString() style.
          */
-        public stringStyle = CompositeOperation.CompositionStringStyle.Normal
+        public stringStyle = CompositeOperation.CompositionStringStyle.NORMAL
 
         /**
          * A set of prefixes to include in a decorated .toString().
@@ -157,9 +157,9 @@ export namespace composition {
 
         toString() {
             switch (this.stringStyle) {
-                case CompositeOperation.CompositionStringStyle.Normal:
+                case CompositeOperation.CompositionStringStyle.NORMAL:
                     return this.expression.toString();
-                case CompositeOperation.CompositionStringStyle.Decorated:
+                case CompositeOperation.CompositionStringStyle.DECORATED:
                     return this.decorationPrefixes.join('') + this.expression.toString() + this.decorationPostfixes.join('');
                 default:
                     throw new Error(`Unknown string style: ${this.stringStyle}`);
@@ -173,10 +173,10 @@ export namespace composition {
          */
         export enum CompositionStringStyle {
             /** Normal string expression */
-            Normal,
+            NORMAL,
 
             /** Decorated string expression */
-            Decorated
+            DECORATED
         }
     }
 }
diff --git a/packages/jsii-calc/lib/compliance.ts b/packages/jsii-calc/lib/compliance.ts
index a5194ccd75..cff955bd89 100644
--- a/packages/jsii-calc/lib/compliance.ts
+++ b/packages/jsii-calc/lib/compliance.ts
@@ -21,9 +21,9 @@ import base = require('@scope/jsii-calc-base');
 const readFile = promisify(fs.readFile);
 
 export enum AllTypesEnum {
-    MyEnumValue,
-    YourEnumValue = 100,
-    ThisIsGreat
+    MY_ENUM_VALUE,
+    YOUR_ENUM_VALUE = 100,
+    THIS_IS_GREAT
 }
 
 export enum StringEnum {
@@ -169,7 +169,7 @@ export class AllTypes {
     // enum
 
     public optionalEnumValue?: StringEnum;
-    private enumValue: AllTypesEnum = AllTypesEnum.ThisIsGreat;
+    private enumValue: AllTypesEnum = AllTypesEnum.THIS_IS_GREAT;
 
     get enumProperty() {
         return this.enumValue;
@@ -178,9 +178,9 @@ export class AllTypes {
     set enumProperty(value: AllTypesEnum) {
         this.enumValue = value;
         switch (value) {
-            case AllTypesEnum.MyEnumValue:
-            case AllTypesEnum.YourEnumValue:
-            case AllTypesEnum.ThisIsGreat:
+            case AllTypesEnum.MY_ENUM_VALUE:
+            case AllTypesEnum.YOUR_ENUM_VALUE:
+            case AllTypesEnum.THIS_IS_GREAT:
                 return;
             default:
                 throw new Error('Invalid enum: ' + value);
@@ -1008,7 +1008,7 @@ export interface ImplictBaseOfBase extends base.BaseProps {
  * See awslabs/jsii#138
  */
 export class ReferenceEnumFromScopedPackage {
-    public foo?: EnumFromScopedModule = EnumFromScopedModule.Value2;
+    public foo?: EnumFromScopedModule = EnumFromScopedModule.VALUE2;
 
     public loadFoo(): EnumFromScopedModule | undefined {
         return this.foo;
@@ -1594,7 +1594,7 @@ export abstract class PartiallyInitializedThisConsumer {
 
 export class ConstructorPassesThisOut {
     constructor(consumer: PartiallyInitializedThisConsumer) {
-        const result = consumer.consumePartiallyInitializedThis(this, new Date(0), AllTypesEnum.ThisIsGreat);
+        const result = consumer.consumePartiallyInitializedThis(this, new Date(0), AllTypesEnum.THIS_IS_GREAT);
         if (result !== 'OK') {
             throw new Error(`Expected OK but received ${result}`);
         }
@@ -1702,13 +1702,13 @@ export class SingletonString {
     private constructor() { }
 
     public isSingletonString(value: string): boolean {
-        return value === SingletonStringEnum.SingletonString;
+        return value === SingletonStringEnum.SINGLETON_STRING;
     }
 }
 /** A singleton string */
 export enum SingletonStringEnum {
     /** 1337 */
-    SingletonString = '3L1T3!'
+    SINGLETON_STRING = '3L1T3!'
 }
 /**
  * Verifies that singleton enums are handled correctly
@@ -1718,11 +1718,11 @@ export enum SingletonStringEnum {
 export class SingletonInt {
     private constructor() { }
     public isSingletonInt(value: number): boolean {
-        return value === SingletonIntEnum.SingletonInt;
+        return value === SingletonIntEnum.SINGLETON_INT;
     }
 }
 /** A singleton integer. */
 export enum SingletonIntEnum {
     /** Elite! */
-    SingletonInt = 1337
+    SINGLETON_INT = 1337
 }
diff --git a/packages/jsii-calc/lib/stability.ts b/packages/jsii-calc/lib/stability.ts
index 7fb132b0df..f9b75a19f1 100644
--- a/packages/jsii-calc/lib/stability.ts
+++ b/packages/jsii-calc/lib/stability.ts
@@ -30,9 +30,9 @@ export class ExperimentalClass {
 /** @experimental */
 export enum ExperimentalEnum {
   /** @experimental */
-  OptionA,
+  OPTION_A,
   /** @experimental */
-  OptionB
+  OPTION_B
 }
 
 /** @stable */
@@ -64,9 +64,9 @@ export class StableClass {
 /** @stable */
 export enum StableEnum {
   /** @stable */
-  OptionA,
+  OPTION_A,
   /** @stable */
-  OptionB
+  OPTION_B
 }
 
 /** @deprecated it just wraps a string */
@@ -98,7 +98,7 @@ export class DeprecatedClass {
 /** @deprecated your deprecated selection of bad options */
 export enum DeprecatedEnum {
   /** @deprecated option A is not great */
-  OptionA,
+  OPTION_A,
   /** @deprecated option B is kinda bad, too */
-  OptionB
+  OPTION_B
 }
diff --git a/packages/jsii-calc/test/assembly.jsii b/packages/jsii-calc/test/assembly.jsii
index f13248045e..d5ede687e7 100644
--- a/packages/jsii-calc/test/assembly.jsii
+++ b/packages/jsii-calc/test/assembly.jsii
@@ -892,19 +892,19 @@
           "docs": {
             "stability": "experimental"
           },
-          "name": "MyEnumValue"
+          "name": "MY_ENUM_VALUE"
         },
         {
           "docs": {
             "stability": "experimental"
           },
-          "name": "YourEnumValue"
+          "name": "YOUR_ENUM_VALUE"
         },
         {
           "docs": {
             "stability": "experimental"
           },
-          "name": "ThisIsGreat"
+          "name": "THIS_IS_GREAT"
         }
       ],
       "name": "AllTypesEnum"
@@ -2262,14 +2262,14 @@
             "deprecated": "option A is not great",
             "stability": "deprecated"
           },
-          "name": "OptionA"
+          "name": "OPTION_A"
         },
         {
           "docs": {
             "deprecated": "option B is kinda bad, too",
             "stability": "deprecated"
           },
-          "name": "OptionB"
+          "name": "OPTION_B"
         }
       ],
       "name": "DeprecatedEnum"
@@ -2972,13 +2972,13 @@
           "docs": {
             "stability": "experimental"
           },
-          "name": "OptionA"
+          "name": "OPTION_A"
         },
         {
           "docs": {
             "stability": "experimental"
           },
-          "name": "OptionB"
+          "name": "OPTION_B"
         }
       ],
       "name": "ExperimentalEnum"
@@ -7179,7 +7179,7 @@
             "stability": "experimental",
             "summary": "Elite!"
           },
-          "name": "SingletonInt"
+          "name": "SINGLETON_INT"
         }
       ],
       "name": "SingletonIntEnum"
@@ -7242,7 +7242,7 @@
             "stability": "experimental",
             "summary": "1337."
           },
-          "name": "SingletonString"
+          "name": "SINGLETON_STRING"
         }
       ],
       "name": "SingletonStringEnum"
@@ -7338,13 +7338,13 @@
           "docs": {
             "stability": "stable"
           },
-          "name": "OptionA"
+          "name": "OPTION_A"
         },
         {
           "docs": {
             "stability": "stable"
           },
-          "name": "OptionB"
+          "name": "OPTION_B"
         }
       ],
       "name": "StableEnum"
@@ -8759,14 +8759,14 @@
             "stability": "experimental",
             "summary": "Normal string expression."
           },
-          "name": "Normal"
+          "name": "NORMAL"
         },
         {
           "docs": {
             "stability": "experimental",
             "summary": "Decorated string expression."
           },
-          "name": "Decorated"
+          "name": "DECORATED"
         }
       ],
       "name": "CompositionStringStyle",
@@ -8774,5 +8774,5 @@
     }
   },
   "version": "0.11.3",
-  "fingerprint": "PRTiHZmA0R0OqG2aleNqw5twteIgxeOUgjhzIkQMaxg="
+  "fingerprint": "ap5kT9z2b1y6ofObpCic6pDWcRTWCr0ivtq83hsi6ds="
 }
diff --git a/packages/jsii-calc/test/test.calc.ts b/packages/jsii-calc/test/test.calc.ts
index a2bc89a587..c1854818b3 100644
--- a/packages/jsii-calc/test/test.calc.ts
+++ b/packages/jsii-calc/test/test.calc.ts
@@ -30,7 +30,7 @@ calc.neg();   assert.equal(-3200000, calc.value);
 
 calc.curr = new Multiply(new calcLib.Number(2), calc.curr);
 assert.equal(-6400000, calc.value);
-calc.stringStyle = composition.CompositeOperation.CompositionStringStyle.Decorated;
+calc.stringStyle = composition.CompositeOperation.CompositionStringStyle.DECORATED;
 assert.equal(calc.toString(),
     '<<[[{{(2 * -(((((1 * ((0 + 10) * 2)) * ((0 + 10) * 2)) * ((0 + 10) * 2)) * ((0 + 10) * 2)) * ((0 + 10) * 2)))}}]]>>');
 
diff --git a/packages/jsii-diff/test/test.enums.ts b/packages/jsii-diff/test/test.enums.ts
index 664ae2b4d7..fd9d1e5dcb 100644
--- a/packages/jsii-diff/test/test.enums.ts
+++ b/packages/jsii-diff/test/test.enums.ts
@@ -9,14 +9,14 @@ export = {
   async 'okay to add a member to an enum'(test: Test) {
     await expectNoError(test, `
       export enum Foo {
-        Bar,
-        Baz,
+        BAR,
+        BAZ,
       }
     `, `
       export enum Foo {
-        Bar,
-        Baz,
-        Quux
+        BAR,
+        BAZ,
+        QUUX
       }
     `);
     test.done();
@@ -26,17 +26,17 @@ export = {
 
   async 'not okay to remove a member from an enum'(test: Test) {
     await expectError(test,
-      /member Quux has been removed/,
+      /member QUUX has been removed/,
       `
       export enum Foo {
-        Bar,
-        Baz,
-        Quux
+        BAR,
+        BAZ,
+        QUUX
       }
     `, `
       export enum Foo {
-        Bar,
-        Baz
+        BAR,
+        BAZ
       }
     `);
     test.done();
diff --git a/packages/jsii-dotnet-runtime-test/test/Amazon.JSII.Runtime.IntegrationTests/ComplianceTests.cs b/packages/jsii-dotnet-runtime-test/test/Amazon.JSII.Runtime.IntegrationTests/ComplianceTests.cs
index 665ef86872..2e4b1e3b5b 100644
--- a/packages/jsii-dotnet-runtime-test/test/Amazon.JSII.Runtime.IntegrationTests/ComplianceTests.cs
+++ b/packages/jsii-dotnet-runtime-test/test/Amazon.JSII.Runtime.IntegrationTests/ComplianceTests.cs
@@ -260,9 +260,9 @@ public void GetAndSetEnumValues()
 
             calc.Add(9);
             calc.Pow(3);
-            Assert.Equal(CompositionStringStyle.Normal, calc.StringStyle);
-            calc.StringStyle = CompositionStringStyle.Decorated;
-            Assert.Equal(CompositionStringStyle.Decorated, calc.StringStyle);
+            Assert.Equal(CompositionStringStyle.NORMAL, calc.StringStyle);
+            calc.StringStyle = CompositionStringStyle.DECORATED;
+            Assert.Equal(CompositionStringStyle.DECORATED, calc.StringStyle);
             Assert.Equal("<<[[{{(((1 * (0 + 9)) * (0 + 9)) * (0 + 9))}}]]>>", calc.ToString());
         }
 
@@ -270,11 +270,11 @@ public void GetAndSetEnumValues()
         public void UseEnumFromScopedModule()
         {
             ReferenceEnumFromScopedPackage obj = new ReferenceEnumFromScopedPackage();
-            Assert.Equal(EnumFromScopedModule.Value2, obj.Foo);
-            obj.Foo = EnumFromScopedModule.Value1;
-            Assert.Equal(EnumFromScopedModule.Value1, obj.LoadFoo());
-            obj.SaveFoo(EnumFromScopedModule.Value2);
-            Assert.Equal(EnumFromScopedModule.Value2, obj.Foo);
+            Assert.Equal(EnumFromScopedModule.VALUE2, obj.Foo);
+            obj.Foo = EnumFromScopedModule.VALUE1;
+            Assert.Equal(EnumFromScopedModule.VALUE1, obj.LoadFoo());
+            obj.SaveFoo(EnumFromScopedModule.VALUE2);
+            Assert.Equal(EnumFromScopedModule.VALUE2, obj.Foo);
         }
 
         [Fact(DisplayName = Prefix + nameof(UndefinedAndNull))]
@@ -929,7 +929,7 @@ public override String ConsumePartiallyInitializedThis(ConstructorPassesThisOut
             {
                 Assert.NotNull(obj);
                 Assert.Equal(new DateTime(0), dt);
-                Assert.Equal(AllTypesEnum.ThisIsGreat, ev);
+                Assert.Equal(AllTypesEnum.THIS_IS_GREAT, ev);
 
                 return "OK";
             }
diff --git a/packages/jsii-java-runtime-test/project/src/test/java/software/amazon/jsii/testing/ComplianceTest.java b/packages/jsii-java-runtime-test/project/src/test/java/software/amazon/jsii/testing/ComplianceTest.java
index d98dbd1ed2..afd17aba4e 100644
--- a/packages/jsii-java-runtime-test/project/src/test/java/software/amazon/jsii/testing/ComplianceTest.java
+++ b/packages/jsii-java-runtime-test/project/src/test/java/software/amazon/jsii/testing/ComplianceTest.java
@@ -259,20 +259,20 @@ public void getAndSetEnumValues() {
         Calculator calc = new Calculator();
         calc.add(9);
         calc.pow(3);
-        assertEquals(CompositeOperation.CompositionStringStyle.Normal, calc.getStringStyle());
-        calc.setStringStyle(CompositeOperation.CompositionStringStyle.Decorated);
-        assertEquals(CompositeOperation.CompositionStringStyle.Decorated, calc.getStringStyle());
+        assertEquals(CompositeOperation.CompositionStringStyle.NORMAL, calc.getStringStyle());
+        calc.setStringStyle(CompositeOperation.CompositionStringStyle.DECORATED);
+        assertEquals(CompositeOperation.CompositionStringStyle.DECORATED, calc.getStringStyle());
         assertEquals("<<[[{{(((1 * (0 + 9)) * (0 + 9)) * (0 + 9))}}]]>>", calc.toString());
     }
 
     @Test
     public void useEnumFromScopedModule() {
         ReferenceEnumFromScopedPackage obj = new ReferenceEnumFromScopedPackage();
-        assertEquals(EnumFromScopedModule.Value2, obj.getFoo());
-        obj.setFoo(EnumFromScopedModule.Value1);
-        assertEquals(EnumFromScopedModule.Value1, obj.loadFoo());
-        obj.saveFoo(EnumFromScopedModule.Value2);
-        assertEquals(EnumFromScopedModule.Value2, obj.getFoo());
+        assertEquals(EnumFromScopedModule.VALUE2, obj.getFoo());
+        obj.setFoo(EnumFromScopedModule.VALUE1);
+        assertEquals(EnumFromScopedModule.VALUE1, obj.loadFoo());
+        obj.saveFoo(EnumFromScopedModule.VALUE2);
+        assertEquals(EnumFromScopedModule.VALUE2, obj.getFoo());
     }
 
     @Test
@@ -1044,7 +1044,7 @@ public String consumePartiallyInitializedThis(final ConstructorPassesThisOut obj
                                                       final AllTypesEnum en) {
             assertNotNull(obj);
             assertEquals(Instant.EPOCH, dt);
-            assertEquals(AllTypesEnum.ThisIsGreat, en);
+            assertEquals(AllTypesEnum.THIS_IS_GREAT, en);
 
             return "OK";
         }
diff --git a/packages/jsii-kernel/test/test.kernel.ts b/packages/jsii-kernel/test/test.kernel.ts
index cac631a623..a344676082 100644
--- a/packages/jsii-kernel/test/test.kernel.ts
+++ b/packages/jsii-kernel/test/test.kernel.ts
@@ -176,28 +176,28 @@ defineTest('in/out date values', async (test, sandbox) => {
 defineTest('in/out enum values', async (test, sandbox) => {
     const alltypes = sandbox.create({ fqn: 'jsii-calc.AllTypes' });
 
-    sandbox.set({ objref: alltypes, property: 'enumProperty', value: { [api.TOKEN_ENUM]: 'jsii-calc.AllTypesEnum/MyEnumValue' } });
+    sandbox.set({ objref: alltypes, property: 'enumProperty', value: { [api.TOKEN_ENUM]: 'jsii-calc.AllTypesEnum/MY_ENUM_VALUE' } });
     test.equal(sandbox.get({ objref: alltypes, property: 'enumPropertyValue' }).value, 0);
-    sandbox.set({ objref: alltypes, property: 'enumProperty', value: { [api.TOKEN_ENUM]: 'jsii-calc.AllTypesEnum/YourEnumValue' } });
+    sandbox.set({ objref: alltypes, property: 'enumProperty', value: { [api.TOKEN_ENUM]: 'jsii-calc.AllTypesEnum/YOUR_ENUM_VALUE' } });
     test.equal(sandbox.get({ objref: alltypes, property: 'enumPropertyValue' }).value, 100);
-    sandbox.set({ objref: alltypes, property: 'enumProperty', value: { [api.TOKEN_ENUM]: 'jsii-calc.AllTypesEnum/ThisIsGreat' } });
+    sandbox.set({ objref: alltypes, property: 'enumProperty', value: { [api.TOKEN_ENUM]: 'jsii-calc.AllTypesEnum/THIS_IS_GREAT' } });
     test.equal(sandbox.get({ objref: alltypes, property: 'enumPropertyValue' }).value, 101);
-    test.deepEqual(sandbox.get({ objref: alltypes, property: 'enumProperty' }).value, { '$jsii.enum': 'jsii-calc.AllTypesEnum/ThisIsGreat' });
+    test.deepEqual(sandbox.get({ objref: alltypes, property: 'enumProperty' }).value, { '$jsii.enum': 'jsii-calc.AllTypesEnum/THIS_IS_GREAT' });
 });
 
 defineTest('enum values from @scoped packages awslabs/jsii#138', async (test, sandbox) => {
     const objref = sandbox.create({ fqn: 'jsii-calc.ReferenceEnumFromScopedPackage' });
 
     const value = sandbox.get({ objref, property: 'foo' });
-    test.deepEqual(value, { value: { '$jsii.enum': '@scope/jsii-calc-lib.EnumFromScopedModule/Value2' } });
+    test.deepEqual(value, { value: { '$jsii.enum': '@scope/jsii-calc-lib.EnumFromScopedModule/VALUE2' } });
 
-    sandbox.set({ objref, property: 'foo', value: { '$jsii.enum': '@scope/jsii-calc-lib.EnumFromScopedModule/Value1' }});
+    sandbox.set({ objref, property: 'foo', value: { '$jsii.enum': '@scope/jsii-calc-lib.EnumFromScopedModule/VALUE1' }});
     const ret = sandbox.invoke({ objref, method: 'loadFoo' });
-    test.deepEqual(ret, { result: { '$jsii.enum': '@scope/jsii-calc-lib.EnumFromScopedModule/Value1' } });
+    test.deepEqual(ret, { result: { '$jsii.enum': '@scope/jsii-calc-lib.EnumFromScopedModule/VALUE1' } });
 
-    sandbox.invoke({ objref, method: 'saveFoo', args: [ { '$jsii.enum': '@scope/jsii-calc-lib.EnumFromScopedModule/Value2' } ] });
+    sandbox.invoke({ objref, method: 'saveFoo', args: [ { '$jsii.enum': '@scope/jsii-calc-lib.EnumFromScopedModule/VALUE2' } ] });
     const value2 = sandbox.get({ objref, property: 'foo' });
-    test.deepEqual(value2, { value: { '$jsii.enum': '@scope/jsii-calc-lib.EnumFromScopedModule/Value2' } });
+    test.deepEqual(value2, { value: { '$jsii.enum': '@scope/jsii-calc-lib.EnumFromScopedModule/VALUE2' } });
 });
 
 defineTest('fails for invalid enum member name', async (test, sandbox) => {
@@ -1125,7 +1125,7 @@ defineTest('Object ID does not get re-allocated when the constructor passes "thi
         }, {
             [api.TOKEN_DATE]: '1970-01-01T00:00:00.000Z'
         }, {
-            [api.TOKEN_ENUM]: 'jsii-calc.AllTypesEnum/ThisIsGreat'
+            [api.TOKEN_ENUM]: 'jsii-calc.AllTypesEnum/THIS_IS_GREAT'
         }]);
         return 'OK';
     });
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc-lib/dotnet/Amazon.JSII.Tests.CalculatorPackageId.LibPackageId/.jsii b/packages/jsii-pacmak/test/expected.jsii-calc-lib/dotnet/Amazon.JSII.Tests.CalculatorPackageId.LibPackageId/.jsii
index 64ee0bcf09..99adf00bbe 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc-lib/dotnet/Amazon.JSII.Tests.CalculatorPackageId.LibPackageId/.jsii
+++ b/packages/jsii-pacmak/test/expected.jsii-calc-lib/dotnet/Amazon.JSII.Tests.CalculatorPackageId.LibPackageId/.jsii
@@ -136,13 +136,13 @@
           "docs": {
             "stability": "deprecated"
           },
-          "name": "Value1"
+          "name": "VALUE1"
         },
         {
           "docs": {
             "stability": "deprecated"
           },
-          "name": "Value2"
+          "name": "VALUE2"
         }
       ],
       "name": "EnumFromScopedModule"
@@ -540,5 +540,5 @@
     }
   },
   "version": "0.11.3",
-  "fingerprint": "jAkwT5aChzSZi3hTeylIFDPL1J8qUy++0B75C5vIA6Y="
+  "fingerprint": "iggTfEXzBxodU2TEDzkmrmsuEakOvA/UXmOA/8nQboU="
 }
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc-lib/dotnet/Amazon.JSII.Tests.CalculatorPackageId.LibPackageId/Amazon/JSII/Tests/CalculatorNamespace/LibNamespace/EnumFromScopedModule.cs b/packages/jsii-pacmak/test/expected.jsii-calc-lib/dotnet/Amazon.JSII.Tests.CalculatorPackageId.LibPackageId/Amazon/JSII/Tests/CalculatorNamespace/LibNamespace/EnumFromScopedModule.cs
index ba087e2af0..7a826db1f3 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc-lib/dotnet/Amazon.JSII.Tests.CalculatorPackageId.LibPackageId/Amazon/JSII/Tests/CalculatorNamespace/LibNamespace/EnumFromScopedModule.cs
+++ b/packages/jsii-pacmak/test/expected.jsii-calc-lib/dotnet/Amazon.JSII.Tests.CalculatorPackageId.LibPackageId/Amazon/JSII/Tests/CalculatorNamespace/LibNamespace/EnumFromScopedModule.cs
@@ -9,12 +9,12 @@ namespace Amazon.JSII.Tests.CalculatorNamespace.LibNamespace
     public enum EnumFromScopedModule
     {
         /// <remarks>stability: Deprecated</remarks>
-        [JsiiEnumMember(name: "Value1")]
+        [JsiiEnumMember(name: "VALUE1")]
         [System.Obsolete()]
-        Value1,
+        VALUE1,
         /// <remarks>stability: Deprecated</remarks>
-        [JsiiEnumMember(name: "Value2")]
+        [JsiiEnumMember(name: "VALUE2")]
         [System.Obsolete()]
-        Value2
+        VALUE2
     }
 }
\ No newline at end of file
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc-lib/java/src/main/java/software/amazon/jsii/tests/calculator/lib/EnumFromScopedModule.java b/packages/jsii-pacmak/test/expected.jsii-calc-lib/java/src/main/java/software/amazon/jsii/tests/calculator/lib/EnumFromScopedModule.java
index 47bbcb0913..26f684aa91 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc-lib/java/src/main/java/software/amazon/jsii/tests/calculator/lib/EnumFromScopedModule.java
+++ b/packages/jsii-pacmak/test/expected.jsii-calc-lib/java/src/main/java/software/amazon/jsii/tests/calculator/lib/EnumFromScopedModule.java
@@ -12,10 +12,10 @@ public enum EnumFromScopedModule {
      */
     @Deprecated
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Deprecated)
-    Value1,
+    VALUE1,
     /**
      */
     @Deprecated
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Deprecated)
-    Value2,
+    VALUE2,
 }
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc-lib/python/src/scope/jsii_calc_lib/__init__.py b/packages/jsii-pacmak/test/expected.jsii-calc-lib/python/src/scope/jsii_calc_lib/__init__.py
index 79611a4563..931cf1dcdd 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc-lib/python/src/scope/jsii_calc_lib/__init__.py
+++ b/packages/jsii-pacmak/test/expected.jsii-calc-lib/python/src/scope/jsii_calc_lib/__init__.py
@@ -18,12 +18,12 @@ class EnumFromScopedModule(enum.Enum):
     Stability:
         deprecated
     """
-    Value1 = "Value1"
+    VALUE1 = "VALUE1"
     """
     Stability:
         deprecated
     """
-    Value2 = "Value2"
+    VALUE2 = "VALUE2"
     """
     Stability:
         deprecated
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc-lib/sphinx/_scope_jsii-calc-lib.rst b/packages/jsii-pacmak/test/expected.jsii-calc-lib/sphinx/_scope_jsii-calc-lib.rst
index 288683148a..f2b8c752dd 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc-lib/sphinx/_scope_jsii-calc-lib.rst
+++ b/packages/jsii-pacmak/test/expected.jsii-calc-lib/sphinx/_scope_jsii-calc-lib.rst
@@ -154,9 +154,9 @@ EnumFromScopedModule (enum)
 
 
 
-   .. py:data:: Value1
+   .. py:data:: VALUE1
 
-   .. py:data:: Value2
+   .. py:data:: VALUE2
 
 
 IDoublable (interface)
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/.jsii b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/.jsii
index f13248045e..d5ede687e7 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/.jsii
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/.jsii
@@ -892,19 +892,19 @@
           "docs": {
             "stability": "experimental"
           },
-          "name": "MyEnumValue"
+          "name": "MY_ENUM_VALUE"
         },
         {
           "docs": {
             "stability": "experimental"
           },
-          "name": "YourEnumValue"
+          "name": "YOUR_ENUM_VALUE"
         },
         {
           "docs": {
             "stability": "experimental"
           },
-          "name": "ThisIsGreat"
+          "name": "THIS_IS_GREAT"
         }
       ],
       "name": "AllTypesEnum"
@@ -2262,14 +2262,14 @@
             "deprecated": "option A is not great",
             "stability": "deprecated"
           },
-          "name": "OptionA"
+          "name": "OPTION_A"
         },
         {
           "docs": {
             "deprecated": "option B is kinda bad, too",
             "stability": "deprecated"
           },
-          "name": "OptionB"
+          "name": "OPTION_B"
         }
       ],
       "name": "DeprecatedEnum"
@@ -2972,13 +2972,13 @@
           "docs": {
             "stability": "experimental"
           },
-          "name": "OptionA"
+          "name": "OPTION_A"
         },
         {
           "docs": {
             "stability": "experimental"
           },
-          "name": "OptionB"
+          "name": "OPTION_B"
         }
       ],
       "name": "ExperimentalEnum"
@@ -7179,7 +7179,7 @@
             "stability": "experimental",
             "summary": "Elite!"
           },
-          "name": "SingletonInt"
+          "name": "SINGLETON_INT"
         }
       ],
       "name": "SingletonIntEnum"
@@ -7242,7 +7242,7 @@
             "stability": "experimental",
             "summary": "1337."
           },
-          "name": "SingletonString"
+          "name": "SINGLETON_STRING"
         }
       ],
       "name": "SingletonStringEnum"
@@ -7338,13 +7338,13 @@
           "docs": {
             "stability": "stable"
           },
-          "name": "OptionA"
+          "name": "OPTION_A"
         },
         {
           "docs": {
             "stability": "stable"
           },
-          "name": "OptionB"
+          "name": "OPTION_B"
         }
       ],
       "name": "StableEnum"
@@ -8759,14 +8759,14 @@
             "stability": "experimental",
             "summary": "Normal string expression."
           },
-          "name": "Normal"
+          "name": "NORMAL"
         },
         {
           "docs": {
             "stability": "experimental",
             "summary": "Decorated string expression."
           },
-          "name": "Decorated"
+          "name": "DECORATED"
         }
       ],
       "name": "CompositionStringStyle",
@@ -8774,5 +8774,5 @@
     }
   },
   "version": "0.11.3",
-  "fingerprint": "PRTiHZmA0R0OqG2aleNqw5twteIgxeOUgjhzIkQMaxg="
+  "fingerprint": "ap5kT9z2b1y6ofObpCic6pDWcRTWCr0ivtq83hsi6ds="
 }
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/AllTypesEnum.cs b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/AllTypesEnum.cs
index 79542cb0b4..cb2743f148 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/AllTypesEnum.cs
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/AllTypesEnum.cs
@@ -7,13 +7,13 @@ namespace Amazon.JSII.Tests.CalculatorNamespace
     public enum AllTypesEnum
     {
         /// <remarks>stability: Experimental</remarks>
-        [JsiiEnumMember(name: "MyEnumValue")]
-        MyEnumValue,
+        [JsiiEnumMember(name: "MY_ENUM_VALUE")]
+        MY_ENUM_VALUE,
         /// <remarks>stability: Experimental</remarks>
-        [JsiiEnumMember(name: "YourEnumValue")]
-        YourEnumValue,
+        [JsiiEnumMember(name: "YOUR_ENUM_VALUE")]
+        YOUR_ENUM_VALUE,
         /// <remarks>stability: Experimental</remarks>
-        [JsiiEnumMember(name: "ThisIsGreat")]
-        ThisIsGreat
+        [JsiiEnumMember(name: "THIS_IS_GREAT")]
+        THIS_IS_GREAT
     }
 }
\ No newline at end of file
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/DeprecatedEnum.cs b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/DeprecatedEnum.cs
index f2a4472519..3aa8714d25 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/DeprecatedEnum.cs
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/DeprecatedEnum.cs
@@ -8,12 +8,12 @@ namespace Amazon.JSII.Tests.CalculatorNamespace
     public enum DeprecatedEnum
     {
         /// <remarks>stability: Deprecated</remarks>
-        [JsiiEnumMember(name: "OptionA")]
+        [JsiiEnumMember(name: "OPTION_A")]
         [System.Obsolete("option A is not great")]
-        OptionA,
+        OPTION_A,
         /// <remarks>stability: Deprecated</remarks>
-        [JsiiEnumMember(name: "OptionB")]
+        [JsiiEnumMember(name: "OPTION_B")]
         [System.Obsolete("option B is kinda bad, too")]
-        OptionB
+        OPTION_B
     }
 }
\ No newline at end of file
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/ExperimentalEnum.cs b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/ExperimentalEnum.cs
index 7337ef57c4..9f81524b2b 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/ExperimentalEnum.cs
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/ExperimentalEnum.cs
@@ -7,10 +7,10 @@ namespace Amazon.JSII.Tests.CalculatorNamespace
     public enum ExperimentalEnum
     {
         /// <remarks>stability: Experimental</remarks>
-        [JsiiEnumMember(name: "OptionA")]
-        OptionA,
+        [JsiiEnumMember(name: "OPTION_A")]
+        OPTION_A,
         /// <remarks>stability: Experimental</remarks>
-        [JsiiEnumMember(name: "OptionB")]
-        OptionB
+        [JsiiEnumMember(name: "OPTION_B")]
+        OPTION_B
     }
 }
\ No newline at end of file
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/SingletonIntEnum.cs b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/SingletonIntEnum.cs
index ac0c53ce28..631314be96 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/SingletonIntEnum.cs
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/SingletonIntEnum.cs
@@ -9,7 +9,7 @@ public enum SingletonIntEnum
     {
         /// <summary>Elite!</summary>
         /// <remarks>stability: Experimental</remarks>
-        [JsiiEnumMember(name: "SingletonInt")]
-        SingletonInt
+        [JsiiEnumMember(name: "SINGLETON_INT")]
+        SINGLETON_INT
     }
 }
\ No newline at end of file
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/SingletonStringEnum.cs b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/SingletonStringEnum.cs
index 4d4556d68e..d538cbc616 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/SingletonStringEnum.cs
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/SingletonStringEnum.cs
@@ -9,7 +9,7 @@ public enum SingletonStringEnum
     {
         /// <summary>1337.</summary>
         /// <remarks>stability: Experimental</remarks>
-        [JsiiEnumMember(name: "SingletonString")]
-        SingletonString
+        [JsiiEnumMember(name: "SINGLETON_STRING")]
+        SINGLETON_STRING
     }
 }
\ No newline at end of file
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/StableEnum.cs b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/StableEnum.cs
index 3e84219846..2fa56c7550 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/StableEnum.cs
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/StableEnum.cs
@@ -7,10 +7,10 @@ namespace Amazon.JSII.Tests.CalculatorNamespace
     public enum StableEnum
     {
         /// <remarks>stability: Stable</remarks>
-        [JsiiEnumMember(name: "OptionA")]
-        OptionA,
+        [JsiiEnumMember(name: "OPTION_A")]
+        OPTION_A,
         /// <remarks>stability: Stable</remarks>
-        [JsiiEnumMember(name: "OptionB")]
-        OptionB
+        [JsiiEnumMember(name: "OPTION_B")]
+        OPTION_B
     }
 }
\ No newline at end of file
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/composition/CompositeOperation/CompositionStringStyle.cs b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/composition/CompositeOperation/CompositionStringStyle.cs
index db1a9bf7e1..19fbebaf6f 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/composition/CompositeOperation/CompositionStringStyle.cs
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/dotnet/Amazon.JSII.Tests.CalculatorPackageId/Amazon/JSII/Tests/CalculatorNamespace/composition/CompositeOperation/CompositionStringStyle.cs
@@ -9,11 +9,11 @@ public enum CompositionStringStyle
     {
         /// <summary>Normal string expression.</summary>
         /// <remarks>stability: Experimental</remarks>
-        [JsiiEnumMember(name: "Normal")]
-        Normal,
+        [JsiiEnumMember(name: "NORMAL")]
+        NORMAL,
         /// <summary>Decorated string expression.</summary>
         /// <remarks>stability: Experimental</remarks>
-        [JsiiEnumMember(name: "Decorated")]
-        Decorated
+        [JsiiEnumMember(name: "DECORATED")]
+        DECORATED
     }
 }
\ No newline at end of file
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/AllTypesEnum.java b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/AllTypesEnum.java
index 330f74b6d4..5037016559 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/AllTypesEnum.java
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/AllTypesEnum.java
@@ -11,15 +11,15 @@ public enum AllTypesEnum {
      * EXPERIMENTAL
      */
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Experimental)
-    MyEnumValue,
+    MY_ENUM_VALUE,
     /**
      * EXPERIMENTAL
      */
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Experimental)
-    YourEnumValue,
+    YOUR_ENUM_VALUE,
     /**
      * EXPERIMENTAL
      */
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Experimental)
-    ThisIsGreat,
+    THIS_IS_GREAT,
 }
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/DeprecatedEnum.java b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/DeprecatedEnum.java
index 2200438388..35e8b9bb14 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/DeprecatedEnum.java
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/DeprecatedEnum.java
@@ -13,11 +13,11 @@ public enum DeprecatedEnum {
      */
     @Deprecated
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Deprecated)
-    OptionA,
+    OPTION_A,
     /**
      * @deprecated option B is kinda bad, too
      */
     @Deprecated
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Deprecated)
-    OptionB,
+    OPTION_B,
 }
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/ExperimentalEnum.java b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/ExperimentalEnum.java
index 068e43779e..f4fdd8d755 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/ExperimentalEnum.java
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/ExperimentalEnum.java
@@ -11,10 +11,10 @@ public enum ExperimentalEnum {
      * EXPERIMENTAL
      */
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Experimental)
-    OptionA,
+    OPTION_A,
     /**
      * EXPERIMENTAL
      */
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Experimental)
-    OptionB,
+    OPTION_B,
 }
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/SingletonIntEnum.java b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/SingletonIntEnum.java
index 976868f731..7f7f834ce2 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/SingletonIntEnum.java
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/SingletonIntEnum.java
@@ -15,5 +15,5 @@ public enum SingletonIntEnum {
      * EXPERIMENTAL
      */
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Experimental)
-    SingletonInt,
+    SINGLETON_INT,
 }
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/SingletonStringEnum.java b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/SingletonStringEnum.java
index 7c2a5e84d2..d35515a569 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/SingletonStringEnum.java
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/SingletonStringEnum.java
@@ -15,5 +15,5 @@ public enum SingletonStringEnum {
      * EXPERIMENTAL
      */
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Experimental)
-    SingletonString,
+    SINGLETON_STRING,
 }
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/StableEnum.java b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/StableEnum.java
index a150455ab7..7bc834ceba 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/StableEnum.java
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/StableEnum.java
@@ -9,9 +9,9 @@ public enum StableEnum {
     /**
      */
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Stable)
-    OptionA,
+    OPTION_A,
     /**
      */
     @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Stable)
-    OptionB,
+    OPTION_B,
 }
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/composition/CompositeOperation.java b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/composition/CompositeOperation.java
index a1a4c9e8dc..ac9d9ef296 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/composition/CompositeOperation.java
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/java/src/main/java/software/amazon/jsii/tests/calculator/composition/CompositeOperation.java
@@ -122,14 +122,14 @@ public enum CompositionStringStyle {
          * EXPERIMENTAL
          */
         @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Experimental)
-        Normal,
+        NORMAL,
         /**
          * Decorated string expression.
          * 
          * EXPERIMENTAL
          */
         @software.amazon.jsii.Stability(software.amazon.jsii.Stability.Level.Experimental)
-        Decorated,
+        DECORATED,
     }
 
     /**
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/python/src/jsii_calc/__init__.py b/packages/jsii-pacmak/test/expected.jsii-calc/python/src/jsii_calc/__init__.py
index f3a90c217c..993713dc17 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/python/src/jsii_calc/__init__.py
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/python/src/jsii_calc/__init__.py
@@ -373,17 +373,17 @@ class AllTypesEnum(enum.Enum):
     Stability:
         experimental
     """
-    MyEnumValue = "MyEnumValue"
+    MY_ENUM_VALUE = "MY_ENUM_VALUE"
     """
     Stability:
         experimental
     """
-    YourEnumValue = "YourEnumValue"
+    YOUR_ENUM_VALUE = "YOUR_ENUM_VALUE"
     """
     Stability:
         experimental
     """
-    ThisIsGreat = "ThisIsGreat"
+    THIS_IS_GREAT = "THIS_IS_GREAT"
     """
     Stability:
         experimental
@@ -929,7 +929,7 @@ class DeprecatedEnum(enum.Enum):
     Stability:
         deprecated
     """
-    OptionA = "OptionA"
+    OPTION_A = "OPTION_A"
     """
     Deprecated:
         option A is not great
@@ -937,7 +937,7 @@ class DeprecatedEnum(enum.Enum):
     Stability:
         deprecated
     """
-    OptionB = "OptionB"
+    OPTION_B = "OPTION_B"
     """
     Deprecated:
         option B is kinda bad, too
@@ -1287,12 +1287,12 @@ class ExperimentalEnum(enum.Enum):
     Stability:
         experimental
     """
-    OptionA = "OptionA"
+    OPTION_A = "OPTION_A"
     """
     Stability:
         experimental
     """
-    OptionB = "OptionB"
+    OPTION_B = "OPTION_B"
     """
     Stability:
         experimental
@@ -4745,7 +4745,7 @@ class SingletonIntEnum(enum.Enum):
     Stability:
         experimental
     """
-    SingletonInt = "SingletonInt"
+    SINGLETON_INT = "SINGLETON_INT"
     """Elite!
 
     Stability:
@@ -4779,7 +4779,7 @@ class SingletonStringEnum(enum.Enum):
     Stability:
         experimental
     """
-    SingletonString = "SingletonString"
+    SINGLETON_STRING = "SINGLETON_STRING"
     """1337.
 
     Stability:
@@ -4839,12 +4839,12 @@ class StableEnum(enum.Enum):
     Stability:
         stable
     """
-    OptionA = "OptionA"
+    OPTION_A = "OPTION_A"
     """
     Stability:
         stable
     """
-    OptionB = "OptionB"
+    OPTION_B = "OPTION_B"
     """
     Stability:
         stable
@@ -5713,13 +5713,13 @@ class CompositionStringStyle(enum.Enum):
             Stability:
                 experimental
             """
-            Normal = "Normal"
+            NORMAL = "NORMAL"
             """Normal string expression.
 
             Stability:
                 experimental
             """
-            Decorated = "Decorated"
+            DECORATED = "DECORATED"
             """Decorated string expression.
 
             Stability:
diff --git a/packages/jsii-pacmak/test/expected.jsii-calc/sphinx/jsii-calc.rst b/packages/jsii-pacmak/test/expected.jsii-calc/sphinx/jsii-calc.rst
index 151d4708cd..61da53ff0a 100644
--- a/packages/jsii-pacmak/test/expected.jsii-calc/sphinx/jsii-calc.rst
+++ b/packages/jsii-pacmak/test/expected.jsii-calc/sphinx/jsii-calc.rst
@@ -538,11 +538,11 @@ AllTypesEnum (enum)
 
 
 
-   .. py:data:: MyEnumValue
+   .. py:data:: MY_ENUM_VALUE
 
-   .. py:data:: YourEnumValue
+   .. py:data:: YOUR_ENUM_VALUE
 
-   .. py:data:: ThisIsGreat
+   .. py:data:: THIS_IS_GREAT
 
 
 AllowedMethodNames
@@ -1562,9 +1562,9 @@ DeprecatedEnum (enum)
 
 
 
-   .. py:data:: OptionA
+   .. py:data:: OPTION_A
 
-   .. py:data:: OptionB
+   .. py:data:: OPTION_B
 
 
 DeprecatedStruct (interface)
@@ -2198,9 +2198,9 @@ ExperimentalEnum (enum)
 
 
 
-   .. py:data:: OptionA
+   .. py:data:: OPTION_A
 
-   .. py:data:: OptionB
+   .. py:data:: OPTION_B
 
 
 ExperimentalStruct (interface)
@@ -5905,7 +5905,7 @@ SingletonIntEnum (enum)
 
 
 
-   .. py:data:: SingletonInt
+   .. py:data:: SINGLETON_INT
 
    Elite!
 
@@ -5986,7 +5986,7 @@ SingletonStringEnum (enum)
 
 
 
-   .. py:data:: SingletonString
+   .. py:data:: SINGLETON_STRING
 
    1337.
 
@@ -6066,9 +6066,9 @@ StableEnum (enum)
 
 
 
-   .. py:data:: OptionA
+   .. py:data:: OPTION_A
 
-   .. py:data:: OptionB
+   .. py:data:: OPTION_B
 
 
 StableStruct (interface)
@@ -7133,13 +7133,13 @@ CompositeOperation
 
 
 
-      .. py:data:: Normal
+      .. py:data:: NORMAL
 
       Normal string expression.
 
 
 
-      .. py:data:: Decorated
+      .. py:data:: DECORATED
 
       Decorated string expression.
 
diff --git a/packages/jsii-python-runtime/tests/test_compliance.py b/packages/jsii-python-runtime/tests/test_compliance.py
index 4ba2ffe6d5..bb66566bcf 100644
--- a/packages/jsii-python-runtime/tests/test_compliance.py
+++ b/packages/jsii-python-runtime/tests/test_compliance.py
@@ -343,21 +343,21 @@ def test_getAndSetEnumValues():
 
     CompositeOperation = composition.CompositeOperation
 
-    assert calc.string_style == CompositeOperation.CompositionStringStyle.Normal
+    assert calc.string_style == CompositeOperation.CompositionStringStyle.NORMAL
 
-    calc.string_style = CompositeOperation.CompositionStringStyle.Decorated
+    calc.string_style = CompositeOperation.CompositionStringStyle.DECORATED
 
-    assert calc.string_style == CompositeOperation.CompositionStringStyle.Decorated
+    assert calc.string_style == CompositeOperation.CompositionStringStyle.DECORATED
     assert calc.to_string() == "<<[[{{(((1 * (0 + 9)) * (0 + 9)) * (0 + 9))}}]]>>"
 
 
 def test_useEnumFromScopedModule():
     obj = ReferenceEnumFromScopedPackage()
-    assert obj.foo == EnumFromScopedModule.Value2
-    obj.foo = EnumFromScopedModule.Value1
-    assert obj.load_foo() == EnumFromScopedModule.Value1
-    obj.save_foo(EnumFromScopedModule.Value2)
-    assert obj.foo == EnumFromScopedModule.Value2
+    assert obj.foo == EnumFromScopedModule.VALUE2
+    obj.foo = EnumFromScopedModule.VALUE1
+    assert obj.load_foo() == EnumFromScopedModule.VALUE1
+    obj.save_foo(EnumFromScopedModule.VALUE2)
+    assert obj.foo == EnumFromScopedModule.VALUE2
 
 
 def test_undefinedAndNull():
@@ -890,7 +890,7 @@ class PartiallyInitializedThisConsumerImpl(PartiallyInitializedThisConsumer):
         def consume_partially_initialized_this(self, obj, dt, en):
             assert obj is not None
             assert isinstance(dt, datetime)
-            assert en.member == AllTypesEnum.ThisIsGreat.value
+            assert en.member == AllTypesEnum.THIS_IS_GREAT.value
             return "OK"
 
     reflector = PartiallyInitializedThisConsumerImpl()
diff --git a/packages/jsii-reflect/actual.txt b/packages/jsii-reflect/actual.txt
index bf6751fec7..7df10da8b9 100644
--- a/packages/jsii-reflect/actual.txt
+++ b/packages/jsii-reflect/actual.txt
@@ -1107,16 +1107,16 @@ assemblies
  │   │     ├── abstract
  │   │     └── type: primitive:string | primitive:number
  │   ├─┬ AllTypesEnum enum
- │   │ ├── MyEnumValue
- │   │ ├── YourEnumValue
- │   │ └── ThisIsGreat
+ │   │ ├── MY_ENUM_VALUE
+ │   │ ├── YOUR_ENUM_VALUE
+ │   │ └── THIS_IS_GREAT
  │   ├─┬ StringEnum enum
  │   │ ├── A
  │   │ ├── B
  │   │ └── C
  │   └─┬ CompositionStringStyle enum
- │     ├── Normal
- │     └── Decorated
+ │     ├── NORMAL
+ │     └── DECORATED
  ├─┬ @scope/jsii-calc-base
  │ ├─┬ dependencies
  │ │ └── @scope/jsii-calc-base-of-base
@@ -1219,5 +1219,5 @@ assemblies
      │     ├── abstract
      │     └── type: primitive:boolean (optional)
      └─┬ EnumFromScopedModule enum
-       ├── Value1
-       └── Value2
+       ├── VALUE1
+       └── VALUE2
diff --git a/packages/jsii-reflect/test/jsii-tree.test.all.expected.txt b/packages/jsii-reflect/test/jsii-tree.test.all.expected.txt
index e813402066..5cd76b3f67 100644
--- a/packages/jsii-reflect/test/jsii-tree.test.all.expected.txt
+++ b/packages/jsii-reflect/test/jsii-tree.test.all.expected.txt
@@ -1593,29 +1593,29 @@ assemblies
  │   │     ├── immutable
  │   │     └── type: Optional<string | number>
  │   ├─┬ enum AllTypesEnum
- │   │ ├── MyEnumValue
- │   │ ├── YourEnumValue
- │   │ └── ThisIsGreat
+ │   │ ├── MY_ENUM_VALUE
+ │   │ ├── YOUR_ENUM_VALUE
+ │   │ └── THIS_IS_GREAT
  │   ├─┬ enum DeprecatedEnum
- │   │ ├── OptionA
- │   │ └── OptionB
+ │   │ ├── OPTION_A
+ │   │ └── OPTION_B
  │   ├─┬ enum ExperimentalEnum
- │   │ ├── OptionA
- │   │ └── OptionB
+ │   │ ├── OPTION_A
+ │   │ └── OPTION_B
  │   ├─┬ enum SingletonIntEnum
- │   │ └── SingletonInt
+ │   │ └── SINGLETON_INT
  │   ├─┬ enum SingletonStringEnum
- │   │ └── SingletonString
+ │   │ └── SINGLETON_STRING
  │   ├─┬ enum StableEnum
- │   │ ├── OptionA
- │   │ └── OptionB
+ │   │ ├── OPTION_A
+ │   │ └── OPTION_B
  │   ├─┬ enum StringEnum
  │   │ ├── A
  │   │ ├── B
  │   │ └── C
  │   └─┬ enum CompositionStringStyle
- │     ├── Normal
- │     └── Decorated
+ │     ├── NORMAL
+ │     └── DECORATED
  ├─┬ @scope/jsii-calc-base
  │ ├─┬ dependencies
  │ │ └── @scope/jsii-calc-base-of-base
@@ -1740,5 +1740,5 @@ assemblies
      │     ├── immutable
      │     └── type: Optional<boolean>
      └─┬ enum EnumFromScopedModule
-       ├── Value1
-       └── Value2
+       ├── VALUE1
+       └── VALUE2
diff --git a/packages/jsii-reflect/test/jsii-tree.test.members.expected.txt b/packages/jsii-reflect/test/jsii-tree.test.members.expected.txt
index 6f0e05404e..befa545763 100644
--- a/packages/jsii-reflect/test/jsii-tree.test.members.expected.txt
+++ b/packages/jsii-reflect/test/jsii-tree.test.members.expected.txt
@@ -707,29 +707,29 @@ assemblies
  │   │   ├── bar property
  │   │   └── foo property
  │   ├─┬ enum AllTypesEnum
- │   │ ├── MyEnumValue
- │   │ ├── YourEnumValue
- │   │ └── ThisIsGreat
+ │   │ ├── MY_ENUM_VALUE
+ │   │ ├── YOUR_ENUM_VALUE
+ │   │ └── THIS_IS_GREAT
  │   ├─┬ enum DeprecatedEnum
- │   │ ├── OptionA
- │   │ └── OptionB
+ │   │ ├── OPTION_A
+ │   │ └── OPTION_B
  │   ├─┬ enum ExperimentalEnum
- │   │ ├── OptionA
- │   │ └── OptionB
+ │   │ ├── OPTION_A
+ │   │ └── OPTION_B
  │   ├─┬ enum SingletonIntEnum
- │   │ └── SingletonInt
+ │   │ └── SINGLETON_INT
  │   ├─┬ enum SingletonStringEnum
- │   │ └── SingletonString
+ │   │ └── SINGLETON_STRING
  │   ├─┬ enum StableEnum
- │   │ ├── OptionA
- │   │ └── OptionB
+ │   │ ├── OPTION_A
+ │   │ └── OPTION_B
  │   ├─┬ enum StringEnum
  │   │ ├── A
  │   │ ├── B
  │   │ └── C
  │   └─┬ enum CompositionStringStyle
- │     ├── Normal
- │     └── Decorated
+ │     ├── NORMAL
+ │     └── DECORATED
  ├─┬ @scope/jsii-calc-base
  │ └─┬ types
  │   ├─┬ class Base
@@ -790,5 +790,5 @@ assemblies
      │   ├── optional2 property
      │   └── optional3 property
      └─┬ enum EnumFromScopedModule
-       ├── Value1
-       └── Value2
+       ├── VALUE1
+       └── VALUE2
diff --git a/packages/jsii-reflect/test/tree.expected.txt b/packages/jsii-reflect/test/tree.expected.txt
index bf6751fec7..7df10da8b9 100644
--- a/packages/jsii-reflect/test/tree.expected.txt
+++ b/packages/jsii-reflect/test/tree.expected.txt
@@ -1107,16 +1107,16 @@ assemblies
  │   │     ├── abstract
  │   │     └── type: primitive:string | primitive:number
  │   ├─┬ AllTypesEnum enum
- │   │ ├── MyEnumValue
- │   │ ├── YourEnumValue
- │   │ └── ThisIsGreat
+ │   │ ├── MY_ENUM_VALUE
+ │   │ ├── YOUR_ENUM_VALUE
+ │   │ └── THIS_IS_GREAT
  │   ├─┬ StringEnum enum
  │   │ ├── A
  │   │ ├── B
  │   │ └── C
  │   └─┬ CompositionStringStyle enum
- │     ├── Normal
- │     └── Decorated
+ │     ├── NORMAL
+ │     └── DECORATED
  ├─┬ @scope/jsii-calc-base
  │ ├─┬ dependencies
  │ │ └── @scope/jsii-calc-base-of-base
@@ -1219,5 +1219,5 @@ assemblies
      │     ├── abstract
      │     └── type: primitive:boolean (optional)
      └─┬ EnumFromScopedModule enum
-       ├── Value1
-       └── Value2
+       ├── VALUE1
+       └── VALUE2
diff --git a/packages/jsii/lib/validator.ts b/packages/jsii/lib/validator.ts
index 2ff4c5895a..1fbecc2836 100644
--- a/packages/jsii/lib/validator.ts
+++ b/packages/jsii/lib/validator.ts
@@ -54,6 +54,7 @@ export type ValidationFunction = (validator: Validator,
 function _defaultValidations(): ValidationFunction[] {
     return [
         _typeNamesMustUsePascalCase,
+        _enumMembersMustUserUpperSnakeCase,
         _memberNamesMustUseCamelCase,
         _staticConstantNamesMustUseUpperSnakeCase,
         _memberNamesMustNotLookLikeJavaGettersOrSetters,
@@ -70,6 +71,19 @@ function _defaultValidations(): ValidationFunction[] {
         }
     }
 
+    function _enumMembersMustUserUpperSnakeCase(_: Validator, assembly: spec.Assembly, diagnostic: DiagnosticEmitter) {
+        for (const type of _allTypes(assembly)) {
+            if (!spec.isEnumType(type)) { continue; }
+
+            for (const member of type.members) {
+                if (member.name && member.name !== Case.constant(member.name)) {
+                    diagnostic(ts.DiagnosticCategory.Error,
+                               `Enum members must use ALL_CAPS: ${member.name}`);
+                }
+            }
+        }
+    }
+
     function _memberNamesMustUseCamelCase(_: Validator, assembly: spec.Assembly, diagnostic: DiagnosticEmitter) {
         for (const member of _allMembers(assembly)) {
             if (member.static && (member as spec.Property).const) { continue; }
diff --git a/packages/jsii/test/negatives/neg.enum-members.1.ts b/packages/jsii/test/negatives/neg.enum-members.1.ts
new file mode 100644
index 0000000000..5e3eae81a0
--- /dev/null
+++ b/packages/jsii/test/negatives/neg.enum-members.1.ts
@@ -0,0 +1,6 @@
+///!MATCH_ERROR: Enum members must use ALL_CAPS: Goo
+
+export enum MyEnum {
+    FOO,
+    Goo
+}
diff --git a/packages/jsii/test/negatives/neg.enum-name.1.ts b/packages/jsii/test/negatives/neg.enum-name.1.ts
index fdc8195e85..6b7732ee76 100644
--- a/packages/jsii/test/negatives/neg.enum-name.1.ts
+++ b/packages/jsii/test/negatives/neg.enum-name.1.ts
@@ -1,6 +1,6 @@
 ///!MATCH_ERROR: Type names must use PascalCase: myEnum
 
 export enum myEnum {
-    Foo,
-    Goo
+    FOO,
+    GOO
 }
diff --git a/packages/jsii/test/negatives/neg.enum-name.2.ts b/packages/jsii/test/negatives/neg.enum-name.2.ts
index fa2acd7b2e..096cf4b267 100644
--- a/packages/jsii/test/negatives/neg.enum-name.2.ts
+++ b/packages/jsii/test/negatives/neg.enum-name.2.ts
@@ -1,6 +1,6 @@
 ///!MATCH_ERROR: Type names must use PascalCase: My_Enum
 
 export enum My_Enum {
-    Foo,
-    Goo
+    FOO,
+    GOO
 }
diff --git a/packages/jsii/test/test.enums.ts b/packages/jsii/test/test.enums.ts
index 2552fbfde0..f148ef784b 100644
--- a/packages/jsii/test/test.enums.ts
+++ b/packages/jsii/test/test.enums.ts
@@ -8,8 +8,8 @@ export = {
   async 'test parsing enum with two members and no values'(test: Test) {
     const assembly = await sourceToAssemblyHelper(`
       export enum Foo {
-        Bar,
-        Baz
+        BAR,
+        BAZ
       }
     `);
 
@@ -17,7 +17,7 @@ export = {
       assembly: 'testpkg',
       fqn: 'testpkg.Foo',
       kind: 'enum',
-      members: [{ name: 'Bar' }, { name: 'Baz' }],
+      members: [{ name: 'BAR' }, { name: 'BAZ' }],
       locationInModule: { filename: 'index.ts', line: 2 },
       name: 'Foo'
     });
@@ -29,8 +29,8 @@ export = {
   async 'test parsing enum with two members and assigned values'(test: Test) {
     const assembly = await sourceToAssemblyHelper(`
       export enum Foo {
-        Bar = 'Bar',
-        Baz = 'Baz'
+        BAR = 'Bar',
+        BAZ = 'Baz'
       }
     `);
 
@@ -38,7 +38,7 @@ export = {
       assembly: 'testpkg',
       fqn: 'testpkg.Foo',
       kind: 'enum',
-      members: [{ name: 'Bar' }, { name: 'Baz' }],
+      members: [{ name: 'BAR' }, { name: 'BAZ' }],
       locationInModule: { filename: 'index.ts', line: 2 },
       name: 'Foo'
     });