diff --git a/integration/oneof-unions-snake/google/protobuf/struct.ts b/integration/oneof-unions-snake/google/protobuf/struct.ts
new file mode 100644
index 000000000..4896a1507
--- /dev/null
+++ b/integration/oneof-unions-snake/google/protobuf/struct.ts
@@ -0,0 +1,515 @@
+/* eslint-disable */
+import * as Long from 'long';
+import * as _m0 from 'protobufjs/minimal';
+
+export const protobufPackage = 'google.protobuf';
+
+/**
+ * `NullValue` is a singleton enumeration to represent the null value for the
+ * `Value` type union.
+ *
+ *  The JSON representation for `NullValue` is JSON `null`.
+ */
+export enum NullValue {
+  /** NULL_VALUE - Null value. */
+  NULL_VALUE = 0,
+  UNRECOGNIZED = -1,
+}
+
+export function nullValueFromJSON(object: any): NullValue {
+  switch (object) {
+    case 0:
+    case 'NULL_VALUE':
+      return NullValue.NULL_VALUE;
+    case -1:
+    case 'UNRECOGNIZED':
+    default:
+      return NullValue.UNRECOGNIZED;
+  }
+}
+
+export function nullValueToJSON(object: NullValue): string {
+  switch (object) {
+    case NullValue.NULL_VALUE:
+      return 'NULL_VALUE';
+    case NullValue.UNRECOGNIZED:
+    default:
+      return 'UNRECOGNIZED';
+  }
+}
+
+/**
+ * `Struct` represents a structured data value, consisting of fields
+ * which map to dynamically typed values. In some languages, `Struct`
+ * might be supported by a native representation. For example, in
+ * scripting languages like JS a struct is represented as an
+ * object. The details of that representation are described together
+ * with the proto support for the language.
+ *
+ * The JSON representation for `Struct` is JSON object.
+ */
+export interface Struct {
+  /** Unordered map of dynamically typed values. */
+  fields: { [key: string]: any | undefined };
+}
+
+export interface Struct_FieldsEntry {
+  key: string;
+  value: any | undefined;
+}
+
+/**
+ * `Value` represents a dynamically typed value which can be either
+ * null, a number, a string, a boolean, a recursive struct value, or a
+ * list of values. A producer of value is expected to set one of these
+ * variants. Absence of any variant indicates an error.
+ *
+ * The JSON representation for `Value` is JSON value.
+ */
+export interface Value {
+  kind?:
+    | { $case: 'null_value'; null_value: NullValue }
+    | { $case: 'number_value'; number_value: number }
+    | { $case: 'string_value'; string_value: string }
+    | { $case: 'bool_value'; bool_value: boolean }
+    | { $case: 'struct_value'; struct_value: { [key: string]: any } | undefined }
+    | { $case: 'list_value'; list_value: Array<any> | undefined };
+}
+
+/**
+ * `ListValue` is a wrapper around a repeated field of values.
+ *
+ * The JSON representation for `ListValue` is JSON array.
+ */
+export interface ListValue {
+  /** Repeated field of dynamically typed values. */
+  values: any[];
+}
+
+function createBaseStruct(): Struct {
+  return { fields: {} };
+}
+
+export const Struct = {
+  encode(message: Struct, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    Object.entries(message.fields).forEach(([key, value]) => {
+      if (value !== undefined) {
+        Struct_FieldsEntry.encode({ key: key as any, value }, writer.uint32(10).fork()).ldelim();
+      }
+    });
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): Struct {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseStruct();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          const entry1 = Struct_FieldsEntry.decode(reader, reader.uint32());
+          if (entry1.value !== undefined) {
+            message.fields[entry1.key] = entry1.value;
+          }
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): Struct {
+    return {
+      fields: isObject(object.fields)
+        ? Object.entries(object.fields).reduce<{ [key: string]: any | undefined }>((acc, [key, value]) => {
+            acc[key] = value as any | undefined;
+            return acc;
+          }, {})
+        : {},
+    };
+  },
+
+  toJSON(message: Struct): unknown {
+    const obj: any = {};
+    obj.fields = {};
+    if (message.fields) {
+      Object.entries(message.fields).forEach(([k, v]) => {
+        obj.fields[k] = v;
+      });
+    }
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<Struct>, I>>(object: I): Struct {
+    const message = createBaseStruct();
+    message.fields = Object.entries(object.fields ?? {}).reduce<{ [key: string]: any | undefined }>(
+      (acc, [key, value]) => {
+        if (value !== undefined) {
+          acc[key] = value;
+        }
+        return acc;
+      },
+      {}
+    );
+    return message;
+  },
+
+  wrap(object: { [key: string]: any } | undefined): Struct {
+    const struct = createBaseStruct();
+    if (object !== undefined) {
+      Object.keys(object).forEach((key) => {
+        struct.fields[key] = object[key];
+      });
+    }
+    return struct;
+  },
+
+  unwrap(message: Struct): { [key: string]: any } {
+    const object: { [key: string]: any } = {};
+    Object.keys(message.fields).forEach((key) => {
+      object[key] = message.fields[key];
+    });
+    return object;
+  },
+};
+
+function createBaseStruct_FieldsEntry(): Struct_FieldsEntry {
+  return { key: '', value: undefined };
+}
+
+export const Struct_FieldsEntry = {
+  encode(message: Struct_FieldsEntry, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    if (message.key !== '') {
+      writer.uint32(10).string(message.key);
+    }
+    if (message.value !== undefined) {
+      Value.encode(Value.wrap(message.value), writer.uint32(18).fork()).ldelim();
+    }
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): Struct_FieldsEntry {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseStruct_FieldsEntry();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          message.key = reader.string();
+          break;
+        case 2:
+          message.value = Value.unwrap(Value.decode(reader, reader.uint32()));
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): Struct_FieldsEntry {
+    return {
+      key: isSet(object.key) ? String(object.key) : '',
+      value: isSet(object?.value) ? object.value : undefined,
+    };
+  },
+
+  toJSON(message: Struct_FieldsEntry): unknown {
+    const obj: any = {};
+    message.key !== undefined && (obj.key = message.key);
+    message.value !== undefined && (obj.value = message.value);
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<Struct_FieldsEntry>, I>>(object: I): Struct_FieldsEntry {
+    const message = createBaseStruct_FieldsEntry();
+    message.key = object.key ?? '';
+    message.value = object.value ?? undefined;
+    return message;
+  },
+};
+
+function createBaseValue(): Value {
+  return { kind: undefined };
+}
+
+export const Value = {
+  encode(message: Value, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    if (message.kind?.$case === 'null_value') {
+      writer.uint32(8).int32(message.kind.null_value);
+    }
+    if (message.kind?.$case === 'number_value') {
+      writer.uint32(17).double(message.kind.number_value);
+    }
+    if (message.kind?.$case === 'string_value') {
+      writer.uint32(26).string(message.kind.string_value);
+    }
+    if (message.kind?.$case === 'bool_value') {
+      writer.uint32(32).bool(message.kind.bool_value);
+    }
+    if (message.kind?.$case === 'struct_value') {
+      Struct.encode(Struct.wrap(message.kind.struct_value), writer.uint32(42).fork()).ldelim();
+    }
+    if (message.kind?.$case === 'list_value') {
+      ListValue.encode(ListValue.wrap(message.kind.list_value), writer.uint32(50).fork()).ldelim();
+    }
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): Value {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseValue();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          message.kind = { $case: 'null_value', null_value: reader.int32() as any };
+          break;
+        case 2:
+          message.kind = { $case: 'number_value', number_value: reader.double() };
+          break;
+        case 3:
+          message.kind = { $case: 'string_value', string_value: reader.string() };
+          break;
+        case 4:
+          message.kind = { $case: 'bool_value', bool_value: reader.bool() };
+          break;
+        case 5:
+          message.kind = { $case: 'struct_value', struct_value: Struct.unwrap(Struct.decode(reader, reader.uint32())) };
+          break;
+        case 6:
+          message.kind = {
+            $case: 'list_value',
+            list_value: ListValue.unwrap(ListValue.decode(reader, reader.uint32())),
+          };
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): Value {
+    return {
+      kind: isSet(object.null_value)
+        ? { $case: 'null_value', null_value: nullValueFromJSON(object.null_value) }
+        : isSet(object.number_value)
+        ? { $case: 'number_value', number_value: Number(object.number_value) }
+        : isSet(object.string_value)
+        ? { $case: 'string_value', string_value: String(object.string_value) }
+        : isSet(object.bool_value)
+        ? { $case: 'bool_value', bool_value: Boolean(object.bool_value) }
+        : isSet(object.struct_value)
+        ? { $case: 'struct_value', struct_value: object.struct_value }
+        : isSet(object.list_value)
+        ? { $case: 'list_value', list_value: [...object.list_value] }
+        : undefined,
+    };
+  },
+
+  toJSON(message: Value): unknown {
+    const obj: any = {};
+    message.kind?.$case === 'null_value' &&
+      (obj.null_value = message.kind?.null_value !== undefined ? nullValueToJSON(message.kind?.null_value) : undefined);
+    message.kind?.$case === 'number_value' && (obj.number_value = message.kind?.number_value);
+    message.kind?.$case === 'string_value' && (obj.string_value = message.kind?.string_value);
+    message.kind?.$case === 'bool_value' && (obj.bool_value = message.kind?.bool_value);
+    message.kind?.$case === 'struct_value' && (obj.struct_value = message.kind?.struct_value);
+    message.kind?.$case === 'list_value' && (obj.list_value = message.kind?.list_value);
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<Value>, I>>(object: I): Value {
+    const message = createBaseValue();
+    if (
+      object.kind?.$case === 'null_value' &&
+      object.kind?.null_value !== undefined &&
+      object.kind?.null_value !== null
+    ) {
+      message.kind = { $case: 'null_value', null_value: object.kind.null_value };
+    }
+    if (
+      object.kind?.$case === 'number_value' &&
+      object.kind?.number_value !== undefined &&
+      object.kind?.number_value !== null
+    ) {
+      message.kind = { $case: 'number_value', number_value: object.kind.number_value };
+    }
+    if (
+      object.kind?.$case === 'string_value' &&
+      object.kind?.string_value !== undefined &&
+      object.kind?.string_value !== null
+    ) {
+      message.kind = { $case: 'string_value', string_value: object.kind.string_value };
+    }
+    if (
+      object.kind?.$case === 'bool_value' &&
+      object.kind?.bool_value !== undefined &&
+      object.kind?.bool_value !== null
+    ) {
+      message.kind = { $case: 'bool_value', bool_value: object.kind.bool_value };
+    }
+    if (
+      object.kind?.$case === 'struct_value' &&
+      object.kind?.struct_value !== undefined &&
+      object.kind?.struct_value !== null
+    ) {
+      message.kind = { $case: 'struct_value', struct_value: object.kind.struct_value };
+    }
+    if (
+      object.kind?.$case === 'list_value' &&
+      object.kind?.list_value !== undefined &&
+      object.kind?.list_value !== null
+    ) {
+      message.kind = { $case: 'list_value', list_value: object.kind.list_value };
+    }
+    return message;
+  },
+
+  wrap(value: any): Value {
+    const result = createBaseValue();
+
+    if (value === null) {
+      result.kind = { $case: 'null_value', null_value: NullValue.NULL_VALUE };
+    } else if (typeof value === 'boolean') {
+      result.kind = { $case: 'bool_value', bool_value: value };
+    } else if (typeof value === 'number') {
+      result.kind = { $case: 'number_value', number_value: value };
+    } else if (typeof value === 'string') {
+      result.kind = { $case: 'string_value', string_value: value };
+    } else if (Array.isArray(value)) {
+      result.kind = { $case: 'list_value', list_value: value };
+    } else if (typeof value === 'object') {
+      result.kind = { $case: 'struct_value', struct_value: value };
+    } else if (typeof value !== 'undefined') {
+      throw new Error('Unsupported any value type: ' + typeof value);
+    }
+
+    return result;
+  },
+
+  unwrap(message: Value): string | number | boolean | Object | null | Array<any> | undefined {
+    if (message.kind?.$case === 'null_value') {
+      return null;
+    } else if (message.kind?.$case === 'number_value') {
+      return message.kind?.number_value;
+    } else if (message.kind?.$case === 'string_value') {
+      return message.kind?.string_value;
+    } else if (message.kind?.$case === 'bool_value') {
+      return message.kind?.bool_value;
+    } else if (message.kind?.$case === 'struct_value') {
+      return message.kind?.struct_value;
+    } else if (message.kind?.$case === 'list_value') {
+      return message.kind?.list_value;
+    } else {
+      return undefined;
+    }
+  },
+};
+
+function createBaseListValue(): ListValue {
+  return { values: [] };
+}
+
+export const ListValue = {
+  encode(message: ListValue, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    for (const v of message.values) {
+      Value.encode(Value.wrap(v!), writer.uint32(10).fork()).ldelim();
+    }
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): ListValue {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseListValue();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          message.values.push(Value.unwrap(Value.decode(reader, reader.uint32())));
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): ListValue {
+    return {
+      values: Array.isArray(object?.values) ? [...object.values] : [],
+    };
+  },
+
+  toJSON(message: ListValue): unknown {
+    const obj: any = {};
+    if (message.values) {
+      obj.values = message.values.map((e) => e);
+    } else {
+      obj.values = [];
+    }
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<ListValue>, I>>(object: I): ListValue {
+    const message = createBaseListValue();
+    message.values = object.values?.map((e) => e) || [];
+    return message;
+  },
+
+  wrap(value: Array<any> | undefined): ListValue {
+    const result = createBaseListValue();
+
+    result.values = value ?? [];
+
+    return result;
+  },
+
+  unwrap(message: ListValue): Array<any> {
+    return message.values;
+  },
+};
+
+type Builtin = Date | Function | Uint8Array | string | number | boolean | undefined;
+
+export type DeepPartial<T> = T extends Builtin
+  ? T
+  : T extends Array<infer U>
+  ? Array<DeepPartial<U>>
+  : T extends ReadonlyArray<infer U>
+  ? ReadonlyArray<DeepPartial<U>>
+  : T extends { $case: string }
+  ? { [K in keyof Omit<T, '$case'>]?: DeepPartial<T[K]> } & { $case: T['$case'] }
+  : T extends {}
+  ? { [K in keyof T]?: DeepPartial<T[K]> }
+  : Partial<T>;
+
+type KeysOfUnion<T> = T extends T ? keyof T : never;
+export type Exact<P, I extends P> = P extends Builtin
+  ? P
+  : P & { [K in keyof P]: Exact<P[K], I[K]> } & Record<Exclude<keyof I, KeysOfUnion<P>>, never>;
+
+// If you get a compile-error about 'Constructor<Long> and ... have no overlap',
+// add '--ts_proto_opt=esModuleInterop=true' as a flag when calling 'protoc'.
+if (_m0.util.Long !== Long) {
+  _m0.util.Long = Long as any;
+  _m0.configure();
+}
+
+function isObject(value: any): boolean {
+  return typeof value === 'object' && value !== null;
+}
+
+function isSet(value: any): boolean {
+  return value !== null && value !== undefined;
+}
diff --git a/integration/oneof-unions-snake/parameters.txt b/integration/oneof-unions-snake/parameters.txt
new file mode 100644
index 000000000..c3bcb3ca8
--- /dev/null
+++ b/integration/oneof-unions-snake/parameters.txt
@@ -0,0 +1 @@
+snakeToCamel=false,oneof=unions
diff --git a/integration/oneof-unions-snake/simple-snake-test.ts b/integration/oneof-unions-snake/simple-snake-test.ts
new file mode 100644
index 000000000..24cca56dd
--- /dev/null
+++ b/integration/oneof-unions-snake/simple-snake-test.ts
@@ -0,0 +1,12 @@
+import { SimpleStruct  } from './simple';
+
+describe('oneof=unions,snakeToCamel=false', () => {
+  it('struct snake case', () => {
+    const simple: SimpleStruct = {
+      simple_struct: {
+        any: 'any'
+      }
+    }
+    expect(simple.simple_struct!['any']).toEqual('any')
+  })
+});
diff --git a/integration/oneof-unions-snake/simple.proto b/integration/oneof-unions-snake/simple.proto
new file mode 100644
index 000000000..1fae26901
--- /dev/null
+++ b/integration/oneof-unions-snake/simple.proto
@@ -0,0 +1,9 @@
+// Adding a comment to the syntax will become the first
+// comment in the output source file.
+syntax = "proto3";
+import "google/protobuf/struct.proto";
+package simple;
+
+message SimpleStruct {
+  google.protobuf.Struct simple_struct = 1;
+}
diff --git a/integration/oneof-unions-snake/simple.ts b/integration/oneof-unions-snake/simple.ts
new file mode 100644
index 000000000..18be427ac
--- /dev/null
+++ b/integration/oneof-unions-snake/simple.ts
@@ -0,0 +1,94 @@
+/* eslint-disable */
+import * as Long from 'long';
+import * as _m0 from 'protobufjs/minimal';
+import { Struct } from './google/protobuf/struct';
+
+export const protobufPackage = 'simple';
+
+/**
+ * Adding a comment to the syntax will become the first
+ * comment in the output source file.
+ */
+
+export interface SimpleStruct {
+  simple_struct: { [key: string]: any } | undefined;
+}
+
+function createBaseSimpleStruct(): SimpleStruct {
+  return { simple_struct: undefined };
+}
+
+export const SimpleStruct = {
+  encode(message: SimpleStruct, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    if (message.simple_struct !== undefined) {
+      Struct.encode(Struct.wrap(message.simple_struct), writer.uint32(10).fork()).ldelim();
+    }
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): SimpleStruct {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseSimpleStruct();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          message.simple_struct = Struct.unwrap(Struct.decode(reader, reader.uint32()));
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): SimpleStruct {
+    return {
+      simple_struct: isObject(object.simple_struct) ? object.simple_struct : undefined,
+    };
+  },
+
+  toJSON(message: SimpleStruct): unknown {
+    const obj: any = {};
+    message.simple_struct !== undefined && (obj.simple_struct = message.simple_struct);
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<SimpleStruct>, I>>(object: I): SimpleStruct {
+    const message = createBaseSimpleStruct();
+    message.simple_struct = object.simple_struct ?? undefined;
+    return message;
+  },
+};
+
+type Builtin = Date | Function | Uint8Array | string | number | boolean | undefined;
+
+export type DeepPartial<T> = T extends Builtin
+  ? T
+  : T extends Array<infer U>
+  ? Array<DeepPartial<U>>
+  : T extends ReadonlyArray<infer U>
+  ? ReadonlyArray<DeepPartial<U>>
+  : T extends { $case: string }
+  ? { [K in keyof Omit<T, '$case'>]?: DeepPartial<T[K]> } & { $case: T['$case'] }
+  : T extends {}
+  ? { [K in keyof T]?: DeepPartial<T[K]> }
+  : Partial<T>;
+
+type KeysOfUnion<T> = T extends T ? keyof T : never;
+export type Exact<P, I extends P> = P extends Builtin
+  ? P
+  : P & { [K in keyof P]: Exact<P[K], I[K]> } & Record<Exclude<keyof I, KeysOfUnion<P>>, never>;
+
+// If you get a compile-error about 'Constructor<Long> and ... have no overlap',
+// add '--ts_proto_opt=esModuleInterop=true' as a flag when calling 'protoc'.
+if (_m0.util.Long !== Long) {
+  _m0.util.Long = Long as any;
+  _m0.configure();
+}
+
+function isObject(value: any): boolean {
+  return typeof value === 'object' && value !== null;
+}
diff --git a/integration/simple-snake/google/protobuf/struct.ts b/integration/simple-snake/google/protobuf/struct.ts
new file mode 100644
index 000000000..e6e54254c
--- /dev/null
+++ b/integration/simple-snake/google/protobuf/struct.ts
@@ -0,0 +1,478 @@
+/* eslint-disable */
+import * as Long from 'long';
+import * as _m0 from 'protobufjs/minimal';
+
+export const protobufPackage = 'google.protobuf';
+
+/**
+ * `NullValue` is a singleton enumeration to represent the null value for the
+ * `Value` type union.
+ *
+ *  The JSON representation for `NullValue` is JSON `null`.
+ */
+export enum NullValue {
+  /** NULL_VALUE - Null value. */
+  NULL_VALUE = 0,
+  UNRECOGNIZED = -1,
+}
+
+export function nullValueFromJSON(object: any): NullValue {
+  switch (object) {
+    case 0:
+    case 'NULL_VALUE':
+      return NullValue.NULL_VALUE;
+    case -1:
+    case 'UNRECOGNIZED':
+    default:
+      return NullValue.UNRECOGNIZED;
+  }
+}
+
+export function nullValueToJSON(object: NullValue): string {
+  switch (object) {
+    case NullValue.NULL_VALUE:
+      return 'NULL_VALUE';
+    case NullValue.UNRECOGNIZED:
+    default:
+      return 'UNRECOGNIZED';
+  }
+}
+
+/**
+ * `Struct` represents a structured data value, consisting of fields
+ * which map to dynamically typed values. In some languages, `Struct`
+ * might be supported by a native representation. For example, in
+ * scripting languages like JS a struct is represented as an
+ * object. The details of that representation are described together
+ * with the proto support for the language.
+ *
+ * The JSON representation for `Struct` is JSON object.
+ */
+export interface Struct {
+  /** Unordered map of dynamically typed values. */
+  fields: { [key: string]: any | undefined };
+}
+
+export interface Struct_FieldsEntry {
+  key: string;
+  value: any | undefined;
+}
+
+/**
+ * `Value` represents a dynamically typed value which can be either
+ * null, a number, a string, a boolean, a recursive struct value, or a
+ * list of values. A producer of value is expected to set one of these
+ * variants. Absence of any variant indicates an error.
+ *
+ * The JSON representation for `Value` is JSON value.
+ */
+export interface Value {
+  /** Represents a null value. */
+  null_value: NullValue | undefined;
+  /** Represents a double value. */
+  number_value: number | undefined;
+  /** Represents a string value. */
+  string_value: string | undefined;
+  /** Represents a boolean value. */
+  bool_value: boolean | undefined;
+  /** Represents a structured value. */
+  struct_value: { [key: string]: any } | undefined;
+  /** Represents a repeated `Value`. */
+  list_value: Array<any> | undefined;
+}
+
+/**
+ * `ListValue` is a wrapper around a repeated field of values.
+ *
+ * The JSON representation for `ListValue` is JSON array.
+ */
+export interface ListValue {
+  /** Repeated field of dynamically typed values. */
+  values: any[];
+}
+
+function createBaseStruct(): Struct {
+  return { fields: {} };
+}
+
+export const Struct = {
+  encode(message: Struct, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    Object.entries(message.fields).forEach(([key, value]) => {
+      if (value !== undefined) {
+        Struct_FieldsEntry.encode({ key: key as any, value }, writer.uint32(10).fork()).ldelim();
+      }
+    });
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): Struct {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseStruct();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          const entry1 = Struct_FieldsEntry.decode(reader, reader.uint32());
+          if (entry1.value !== undefined) {
+            message.fields[entry1.key] = entry1.value;
+          }
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): Struct {
+    return {
+      fields: isObject(object.fields)
+        ? Object.entries(object.fields).reduce<{ [key: string]: any | undefined }>((acc, [key, value]) => {
+            acc[key] = value as any | undefined;
+            return acc;
+          }, {})
+        : {},
+    };
+  },
+
+  toJSON(message: Struct): unknown {
+    const obj: any = {};
+    obj.fields = {};
+    if (message.fields) {
+      Object.entries(message.fields).forEach(([k, v]) => {
+        obj.fields[k] = v;
+      });
+    }
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<Struct>, I>>(object: I): Struct {
+    const message = createBaseStruct();
+    message.fields = Object.entries(object.fields ?? {}).reduce<{ [key: string]: any | undefined }>(
+      (acc, [key, value]) => {
+        if (value !== undefined) {
+          acc[key] = value;
+        }
+        return acc;
+      },
+      {}
+    );
+    return message;
+  },
+
+  wrap(object: { [key: string]: any } | undefined): Struct {
+    const struct = createBaseStruct();
+    if (object !== undefined) {
+      Object.keys(object).forEach((key) => {
+        struct.fields[key] = object[key];
+      });
+    }
+    return struct;
+  },
+
+  unwrap(message: Struct): { [key: string]: any } {
+    const object: { [key: string]: any } = {};
+    Object.keys(message.fields).forEach((key) => {
+      object[key] = message.fields[key];
+    });
+    return object;
+  },
+};
+
+function createBaseStruct_FieldsEntry(): Struct_FieldsEntry {
+  return { key: '', value: undefined };
+}
+
+export const Struct_FieldsEntry = {
+  encode(message: Struct_FieldsEntry, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    if (message.key !== '') {
+      writer.uint32(10).string(message.key);
+    }
+    if (message.value !== undefined) {
+      Value.encode(Value.wrap(message.value), writer.uint32(18).fork()).ldelim();
+    }
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): Struct_FieldsEntry {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseStruct_FieldsEntry();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          message.key = reader.string();
+          break;
+        case 2:
+          message.value = Value.unwrap(Value.decode(reader, reader.uint32()));
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): Struct_FieldsEntry {
+    return {
+      key: isSet(object.key) ? String(object.key) : '',
+      value: isSet(object?.value) ? object.value : undefined,
+    };
+  },
+
+  toJSON(message: Struct_FieldsEntry): unknown {
+    const obj: any = {};
+    message.key !== undefined && (obj.key = message.key);
+    message.value !== undefined && (obj.value = message.value);
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<Struct_FieldsEntry>, I>>(object: I): Struct_FieldsEntry {
+    const message = createBaseStruct_FieldsEntry();
+    message.key = object.key ?? '';
+    message.value = object.value ?? undefined;
+    return message;
+  },
+};
+
+function createBaseValue(): Value {
+  return {
+    null_value: undefined,
+    number_value: undefined,
+    string_value: undefined,
+    bool_value: undefined,
+    struct_value: undefined,
+    list_value: undefined,
+  };
+}
+
+export const Value = {
+  encode(message: Value, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    if (message.null_value !== undefined) {
+      writer.uint32(8).int32(message.null_value);
+    }
+    if (message.number_value !== undefined) {
+      writer.uint32(17).double(message.number_value);
+    }
+    if (message.string_value !== undefined) {
+      writer.uint32(26).string(message.string_value);
+    }
+    if (message.bool_value !== undefined) {
+      writer.uint32(32).bool(message.bool_value);
+    }
+    if (message.struct_value !== undefined) {
+      Struct.encode(Struct.wrap(message.struct_value), writer.uint32(42).fork()).ldelim();
+    }
+    if (message.list_value !== undefined) {
+      ListValue.encode(ListValue.wrap(message.list_value), writer.uint32(50).fork()).ldelim();
+    }
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): Value {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseValue();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          message.null_value = reader.int32() as any;
+          break;
+        case 2:
+          message.number_value = reader.double();
+          break;
+        case 3:
+          message.string_value = reader.string();
+          break;
+        case 4:
+          message.bool_value = reader.bool();
+          break;
+        case 5:
+          message.struct_value = Struct.unwrap(Struct.decode(reader, reader.uint32()));
+          break;
+        case 6:
+          message.list_value = ListValue.unwrap(ListValue.decode(reader, reader.uint32()));
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): Value {
+    return {
+      null_value: isSet(object.null_value) ? nullValueFromJSON(object.null_value) : undefined,
+      number_value: isSet(object.number_value) ? Number(object.number_value) : undefined,
+      string_value: isSet(object.string_value) ? String(object.string_value) : undefined,
+      bool_value: isSet(object.bool_value) ? Boolean(object.bool_value) : undefined,
+      struct_value: isObject(object.struct_value) ? object.struct_value : undefined,
+      list_value: Array.isArray(object.list_value) ? [...object.list_value] : undefined,
+    };
+  },
+
+  toJSON(message: Value): unknown {
+    const obj: any = {};
+    message.null_value !== undefined &&
+      (obj.null_value = message.null_value !== undefined ? nullValueToJSON(message.null_value) : undefined);
+    message.number_value !== undefined && (obj.number_value = message.number_value);
+    message.string_value !== undefined && (obj.string_value = message.string_value);
+    message.bool_value !== undefined && (obj.bool_value = message.bool_value);
+    message.struct_value !== undefined && (obj.struct_value = message.struct_value);
+    message.list_value !== undefined && (obj.list_value = message.list_value);
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<Value>, I>>(object: I): Value {
+    const message = createBaseValue();
+    message.null_value = object.null_value ?? undefined;
+    message.number_value = object.number_value ?? undefined;
+    message.string_value = object.string_value ?? undefined;
+    message.bool_value = object.bool_value ?? undefined;
+    message.struct_value = object.struct_value ?? undefined;
+    message.list_value = object.list_value ?? undefined;
+    return message;
+  },
+
+  wrap(value: any): Value {
+    const result = createBaseValue();
+
+    if (value === null) {
+      result.null_value = NullValue.NULL_VALUE;
+    } else if (typeof value === 'boolean') {
+      result.bool_value = value;
+    } else if (typeof value === 'number') {
+      result.number_value = value;
+    } else if (typeof value === 'string') {
+      result.string_value = value;
+    } else if (Array.isArray(value)) {
+      result.list_value = value;
+    } else if (typeof value === 'object') {
+      result.struct_value = value;
+    } else if (typeof value !== 'undefined') {
+      throw new Error('Unsupported any value type: ' + typeof value);
+    }
+
+    return result;
+  },
+
+  unwrap(message: Value): string | number | boolean | Object | null | Array<any> | undefined {
+    if (message?.string_value !== undefined) {
+      return message.string_value;
+    } else if (message?.number_value !== undefined) {
+      return message.number_value;
+    } else if (message?.bool_value !== undefined) {
+      return message.bool_value;
+    } else if (message?.struct_value !== undefined) {
+      return message.struct_value;
+    } else if (message?.list_value !== undefined) {
+      return message.list_value;
+    } else if (message?.null_value !== undefined) {
+      return null;
+    }
+    return undefined;
+  },
+};
+
+function createBaseListValue(): ListValue {
+  return { values: [] };
+}
+
+export const ListValue = {
+  encode(message: ListValue, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    for (const v of message.values) {
+      Value.encode(Value.wrap(v!), writer.uint32(10).fork()).ldelim();
+    }
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): ListValue {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseListValue();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          message.values.push(Value.unwrap(Value.decode(reader, reader.uint32())));
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): ListValue {
+    return {
+      values: Array.isArray(object?.values) ? [...object.values] : [],
+    };
+  },
+
+  toJSON(message: ListValue): unknown {
+    const obj: any = {};
+    if (message.values) {
+      obj.values = message.values.map((e) => e);
+    } else {
+      obj.values = [];
+    }
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<ListValue>, I>>(object: I): ListValue {
+    const message = createBaseListValue();
+    message.values = object.values?.map((e) => e) || [];
+    return message;
+  },
+
+  wrap(value: Array<any> | undefined): ListValue {
+    const result = createBaseListValue();
+
+    result.values = value ?? [];
+
+    return result;
+  },
+
+  unwrap(message: ListValue): Array<any> {
+    return message.values;
+  },
+};
+
+type Builtin = Date | Function | Uint8Array | string | number | boolean | undefined;
+
+export type DeepPartial<T> = T extends Builtin
+  ? T
+  : T extends Array<infer U>
+  ? Array<DeepPartial<U>>
+  : T extends ReadonlyArray<infer U>
+  ? ReadonlyArray<DeepPartial<U>>
+  : T extends {}
+  ? { [K in keyof T]?: DeepPartial<T[K]> }
+  : Partial<T>;
+
+type KeysOfUnion<T> = T extends T ? keyof T : never;
+export type Exact<P, I extends P> = P extends Builtin
+  ? P
+  : P & { [K in keyof P]: Exact<P[K], I[K]> } & Record<Exclude<keyof I, KeysOfUnion<P>>, never>;
+
+// If you get a compile-error about 'Constructor<Long> and ... have no overlap',
+// add '--ts_proto_opt=esModuleInterop=true' as a flag when calling 'protoc'.
+if (_m0.util.Long !== Long) {
+  _m0.util.Long = Long as any;
+  _m0.configure();
+}
+
+function isObject(value: any): boolean {
+  return typeof value === 'object' && value !== null;
+}
+
+function isSet(value: any): boolean {
+  return value !== null && value !== undefined;
+}
diff --git a/integration/simple-snake/simple-snake-test.ts b/integration/simple-snake/simple-snake-test.ts
index f697f6356..6d8482dc9 100644
--- a/integration/simple-snake/simple-snake-test.ts
+++ b/integration/simple-snake/simple-snake-test.ts
@@ -1,4 +1,4 @@
-import { Child_Type, Simple, StateEnum } from './simple';
+import { Child_Type, Simple, StateEnum, SimpleStruct } from './simple';
 
 const jan1 = new Date('1970-01-01T00:00:00.000Z');
 
@@ -18,4 +18,13 @@ describe('simple', () => {
     };
     expect(simple.name).toEqual('asdf');
   });
+
+  it('struct snake case', () => {
+    const simple: SimpleStruct = {
+      simple_struct: {
+        any: 'any'
+      }
+    }
+    expect(simple.simple_struct!['any']).toEqual('any')
+  })
 });
diff --git a/integration/simple-snake/simple.bin b/integration/simple-snake/simple.bin
index d6a2033ae..8b9d6a264 100644
Binary files a/integration/simple-snake/simple.bin and b/integration/simple-snake/simple.bin differ
diff --git a/integration/simple-snake/simple.proto b/integration/simple-snake/simple.proto
index b7928e59a..e5b6ef747 100644
--- a/integration/simple-snake/simple.proto
+++ b/integration/simple-snake/simple.proto
@@ -3,10 +3,11 @@
 syntax = "proto3";
 import "google/protobuf/wrappers.proto";
 import "google/protobuf/timestamp.proto";
+import "google/protobuf/struct.proto";
 import "import_dir/thing.proto";
 package simple;
 
-// This comment is seperated by a blank non-comment line, and will detatch from 
+// This comment is seperated by a blank non-comment line, and will detatch from
 // the following comment on the message Simple.
 
 /** Example comment on the Simple message */
@@ -119,3 +120,7 @@ message Numbers {
   sfixed32 sfixed32 = 11;
   sfixed64 sfixed64 = 12;
 }
+
+message SimpleStruct {
+  google.protobuf.Struct simple_struct = 1;
+}
diff --git a/integration/simple-snake/simple.ts b/integration/simple-snake/simple.ts
index ed04acc4f..52811afca 100644
--- a/integration/simple-snake/simple.ts
+++ b/integration/simple-snake/simple.ts
@@ -4,6 +4,7 @@ import * as _m0 from 'protobufjs/minimal';
 import { Timestamp } from './google/protobuf/timestamp';
 import { ImportedThing } from './import_dir/thing';
 import { StringValue, Int32Value, BoolValue } from './google/protobuf/wrappers';
+import { Struct } from './google/protobuf/struct';
 
 export const protobufPackage = 'simple';
 
@@ -238,6 +239,10 @@ export interface Numbers {
   sfixed64: number;
 }
 
+export interface SimpleStruct {
+  simple_struct: { [key: string]: any } | undefined;
+}
+
 function createBaseSimple(): Simple {
   return {
     name: '',
@@ -1555,6 +1560,55 @@ export const Numbers = {
   },
 };
 
+function createBaseSimpleStruct(): SimpleStruct {
+  return { simple_struct: undefined };
+}
+
+export const SimpleStruct = {
+  encode(message: SimpleStruct, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
+    if (message.simple_struct !== undefined) {
+      Struct.encode(Struct.wrap(message.simple_struct), writer.uint32(10).fork()).ldelim();
+    }
+    return writer;
+  },
+
+  decode(input: _m0.Reader | Uint8Array, length?: number): SimpleStruct {
+    const reader = input instanceof _m0.Reader ? input : new _m0.Reader(input);
+    let end = length === undefined ? reader.len : reader.pos + length;
+    const message = createBaseSimpleStruct();
+    while (reader.pos < end) {
+      const tag = reader.uint32();
+      switch (tag >>> 3) {
+        case 1:
+          message.simple_struct = Struct.unwrap(Struct.decode(reader, reader.uint32()));
+          break;
+        default:
+          reader.skipType(tag & 7);
+          break;
+      }
+    }
+    return message;
+  },
+
+  fromJSON(object: any): SimpleStruct {
+    return {
+      simple_struct: isObject(object.simple_struct) ? object.simple_struct : undefined,
+    };
+  },
+
+  toJSON(message: SimpleStruct): unknown {
+    const obj: any = {};
+    message.simple_struct !== undefined && (obj.simple_struct = message.simple_struct);
+    return obj;
+  },
+
+  fromPartial<I extends Exact<DeepPartial<SimpleStruct>, I>>(object: I): SimpleStruct {
+    const message = createBaseSimpleStruct();
+    message.simple_struct = object.simple_struct ?? undefined;
+    return message;
+  },
+};
+
 export interface PingService {
   ping(request: PingRequest): Promise<PingResponse>;
 }
diff --git a/src/main.ts b/src/main.ts
index a9ed9eed5..a04303fa2 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -173,8 +173,16 @@ export function generateFile(ctx: Context, fileDesc: FileDescriptorProto): [stri
           staticMembers.push(generateFromPartial(ctx, fullName, message));
         }
 
-        staticMembers.push(...generateWrap(ctx, fullTypeName));
-        staticMembers.push(...generateUnwrap(ctx, fullTypeName));
+        const structFieldNames = {
+          nullValue: maybeSnakeToCamel('null_value', ctx.options),
+          numberValue: maybeSnakeToCamel('number_value', ctx.options),
+          stringValue: maybeSnakeToCamel('string_value', ctx.options),
+          boolValue: maybeSnakeToCamel('bool_value', ctx.options),
+          structValue: maybeSnakeToCamel('struct_value', ctx.options),
+          listValue: maybeSnakeToCamel('list_value', ctx.options),
+        };
+        staticMembers.push(...generateWrap(ctx, fullTypeName, structFieldNames));
+        staticMembers.push(...generateUnwrap(ctx, fullTypeName, structFieldNames));
 
         chunks.push(code`
           export const ${def(fullName)} = {
@@ -1591,7 +1599,16 @@ function generateFromPartial(ctx: Context, fullName: string, messageDesc: Descri
   return joinCode(chunks, { on: '\n' });
 }
 
-function generateWrap(ctx: Context, fullProtoTypeName: string): Code[] {
+type StructFieldNames = {
+  nullValue: string;
+  numberValue: string;
+  stringValue: string;
+  boolValue: string;
+  structValue: string;
+  listValue: string;
+};
+
+function generateWrap(ctx: Context, fullProtoTypeName: string, fieldNames: StructFieldNames): Code[] {
   const chunks: Code[] = [];
   if (isStructTypeName(fullProtoTypeName)) {
     chunks.push(code`wrap(object: {[key: string]: any} | undefined): Struct {
@@ -1611,17 +1628,17 @@ function generateWrap(ctx: Context, fullProtoTypeName: string): Code[] {
         const result = createBaseValue();
 
         if (value === null) {
-          result.kind = {$case: 'nullValue', nullValue: NullValue.NULL_VALUE};
+          result.kind = {$case: '${fieldNames.nullValue}', ${fieldNames.nullValue}: NullValue.NULL_VALUE};
         } else if (typeof value === 'boolean') {
-          result.kind = {$case: 'boolValue', boolValue: value};
+          result.kind = {$case: '${fieldNames.boolValue}', ${fieldNames.boolValue}: value};
         } else if (typeof value === 'number') {
-          result.kind = {$case: 'numberValue', numberValue: value};
+          result.kind = {$case: '${fieldNames.numberValue}', ${fieldNames.numberValue}: value};
         } else if (typeof value === 'string') {
-          result.kind = {$case: 'stringValue', stringValue: value};
+          result.kind = {$case: '${fieldNames.stringValue}', ${fieldNames.stringValue}: value};
         } else if (Array.isArray(value)) {
-          result.kind = {$case: 'listValue', listValue: value};
+          result.kind = {$case: '${fieldNames.listValue}', ${fieldNames.listValue}: value};
         } else if (typeof value === 'object') {
-          result.kind = {$case: 'structValue', structValue: value};
+          result.kind = {$case: '${fieldNames.structValue}', ${fieldNames.structValue}: value};
         } else if (typeof value !== 'undefined') {
           throw new Error('Unsupported any value type: ' + typeof value);
         }
@@ -1633,17 +1650,17 @@ function generateWrap(ctx: Context, fullProtoTypeName: string): Code[] {
         const result = createBaseValue();
 
         if (value === null) {
-          result.nullValue = NullValue.NULL_VALUE;
+          result.${fieldNames.nullValue} = NullValue.NULL_VALUE;
         } else if (typeof value === 'boolean') {
-          result.boolValue = value;
+          result.${fieldNames.boolValue} = value;
         } else if (typeof value === 'number') {
-          result.numberValue = value;
+          result.${fieldNames.numberValue} = value;
         } else if (typeof value === 'string') {
-          result.stringValue = value;
+          result.${fieldNames.stringValue} = value;
         } else if (Array.isArray(value)) {
-          result.listValue = value;
+          result.${fieldNames.listValue} = value;
         } else if (typeof value === 'object') {
-          result.structValue = value;
+          result.${fieldNames.structValue} = value;
         } else if (typeof value !== 'undefined') {
           throw new Error('Unsupported any value type: ' + typeof value);
         }
@@ -1672,7 +1689,7 @@ function generateWrap(ctx: Context, fullProtoTypeName: string): Code[] {
   return chunks;
 }
 
-function generateUnwrap(ctx: Context, fullProtoTypeName: string): Code[] {
+function generateUnwrap(ctx: Context, fullProtoTypeName: string, fieldNames: StructFieldNames): Code[] {
   const chunks: Code[] = [];
   if (isStructTypeName(fullProtoTypeName)) {
     chunks.push(code`unwrap(message: Struct): {[key: string]: any} {
@@ -1687,35 +1704,35 @@ function generateUnwrap(ctx: Context, fullProtoTypeName: string): Code[] {
   if (isAnyValueTypeName(fullProtoTypeName)) {
     if (ctx.options.oneof === OneofOption.UNIONS) {
       chunks.push(code`unwrap(message: Value): string | number | boolean | Object | null | Array<any> | undefined {
-        if (message.kind?.$case === 'nullValue') {
+        if (message.kind?.$case === '${fieldNames.nullValue}') {
           return null;
-        } else if (message.kind?.$case === 'numberValue') {
-          return message.kind?.numberValue;
-        } else if (message.kind?.$case === 'stringValue') {
-          return message.kind?.stringValue;
-        } else if (message.kind?.$case === 'boolValue') {
-          return message.kind?.boolValue;
-        } else if (message.kind?.$case === 'structValue') {
-          return message.kind?.structValue;
-        } else if (message.kind?.$case === 'listValue') {
-          return message.kind?.listValue;
+        } else if (message.kind?.$case === '${fieldNames.numberValue}') {
+          return message.kind?.${fieldNames.numberValue};
+        } else if (message.kind?.$case === '${fieldNames.stringValue}') {
+          return message.kind?.${fieldNames.stringValue};
+        } else if (message.kind?.$case === '${fieldNames.boolValue}') {
+          return message.kind?.${fieldNames.boolValue};
+        } else if (message.kind?.$case === '${fieldNames.structValue}') {
+          return message.kind?.${fieldNames.structValue};
+        } else if (message.kind?.$case === '${fieldNames.listValue}') {
+          return message.kind?.${fieldNames.listValue};
         } else {
           return undefined;
         }
     }`);
     } else {
       chunks.push(code`unwrap(message: Value): string | number | boolean | Object | null | Array<any> | undefined {
-      if (message?.stringValue !== undefined) {
-        return message.stringValue;
-      } else if (message?.numberValue !== undefined) {
-        return message.numberValue;
-      } else if (message?.boolValue !== undefined) {
-        return message.boolValue;
-      } else if (message?.structValue !== undefined) {
-        return message.structValue;
-      } else if (message?.listValue !== undefined) {
-          return message.listValue;
-      } else if (message?.nullValue !== undefined) {
+      if (message?.${fieldNames.stringValue} !== undefined) {
+        return message.${fieldNames.stringValue};
+      } else if (message?.${fieldNames.numberValue} !== undefined) {
+        return message.${fieldNames.numberValue};
+      } else if (message?.${fieldNames.boolValue} !== undefined) {
+        return message.${fieldNames.boolValue};
+      } else if (message?.${fieldNames.structValue} !== undefined) {
+        return message.${fieldNames.structValue};
+      } else if (message?.${fieldNames.listValue} !== undefined) {
+          return message.${fieldNames.listValue};
+      } else if (message?.${fieldNames.nullValue} !== undefined) {
         return null;
       }
       return undefined;