diff --git a/README.md b/README.md
index 62625146b6..176d2bf4c8 100644
--- a/README.md
+++ b/README.md
@@ -571,17 +571,20 @@ public struct Dinosaur {
     /**
      * Common name of this dinosaur, like "Stegosaurus".
      */
+    @Defaulted(defaultValue: "")
     public var name: String?
     /**
      * URLs with images of this dinosaur.
      */
     public var picture_urls: [String] = []
+    @Defaulted(defaultValue: 0)
     public var length_meters: Double?
+    @Defaulted(defaultValue: 0)
     public var mass_kilograms: Double?
     public var period: Period?
     public var unknownFields: Foundation.Data = .init()
 
-    public init(configure: (inout Self) -> Void = { _ in }) {
+    public init(configure: (inout Self) -> Swift.Void = { _ in }) {
         configure(&self)
     }
 
@@ -591,17 +594,18 @@ public struct Dinosaur {
 extension Dinosaur {
 
     @_disfavoredOverload
+    @available(*, deprecated)
     public init(
-        name: String? = nil,
-        picture_urls: [String] = [],
-        length_meters: Double? = nil,
-        mass_kilograms: Double? = nil,
+        name: Swift.String? = nil,
+        picture_urls: [Swift.String] = [],
+        length_meters: Swift.Double? = nil,
+        mass_kilograms: Swift.Double? = nil,
         period: Period? = nil
     ) {
-        self.name = name
+        self._name.wrappedValue = name
         self.picture_urls = picture_urls
-        self.length_meters = length_meters
-        self.mass_kilograms = mass_kilograms
+        self._length_meters.wrappedValue = length_meters
+        self._mass_kilograms.wrappedValue = mass_kilograms
         self.period = period
     }
 
@@ -625,7 +629,7 @@ extension Dinosaur : Sendable {
 
 extension Dinosaur : ProtoMessage {
 
-    public static func protoMessageTypeURL() -> String {
+    public static func protoMessageTypeURL() -> Swift.String {
         return "type.googleapis.com/squareup.dinosaurs.Dinosaur"
     }
 
@@ -633,40 +637,40 @@ extension Dinosaur : ProtoMessage {
 
 extension Dinosaur : Proto2Codable {
 
-    public init(from reader: ProtoReader) throws {
-        var name: String? = nil
-        var picture_urls: [String] = []
-        var length_meters: Double? = nil
-        var mass_kilograms: Double? = nil
+    public init(from protoReader: Wire.ProtoReader) throws {
+        var name: Swift.String? = nil
+        var picture_urls: [Swift.String] = []
+        var length_meters: Swift.Double? = nil
+        var mass_kilograms: Swift.Double? = nil
         var period: Period? = nil
 
-        let token = try reader.beginMessage()
-        while let tag = try reader.nextTag(token: token) {
+        let token = try protoReader.beginMessage()
+        while let tag = try protoReader.nextTag(token: token) {
             switch tag {
-            case 1: name = try reader.decode(String.self)
-            case 2: try reader.decode(into: &picture_urls)
-            case 3: length_meters = try reader.decode(Double.self)
-            case 4: mass_kilograms = try reader.decode(Double.self)
-            case 5: period = try reader.decode(Period.self)
-            default: try reader.readUnknownField(tag: tag)
+            case 1: name = try protoReader.decode(Swift.String.self)
+            case 2: try protoReader.decode(into: &picture_urls)
+            case 3: length_meters = try protoReader.decode(Swift.Double.self)
+            case 4: mass_kilograms = try protoReader.decode(Swift.Double.self)
+            case 5: period = try protoReader.decode(Period.self)
+            default: try protoReader.readUnknownField(tag: tag)
             }
         }
-        self.unknownFields = try reader.endMessage(token: token)
+        self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.name = name
+        self._name.wrappedValue = name
         self.picture_urls = picture_urls
-        self.length_meters = length_meters
-        self.mass_kilograms = mass_kilograms
+        self._length_meters.wrappedValue = length_meters
+        self._mass_kilograms.wrappedValue = mass_kilograms
         self.period = period
     }
 
-    public func encode(to writer: ProtoWriter) throws {
-        try writer.encode(tag: 1, value: self.name)
-        try writer.encode(tag: 2, value: self.picture_urls)
-        try writer.encode(tag: 3, value: self.length_meters)
-        try writer.encode(tag: 4, value: self.mass_kilograms)
-        try writer.encode(tag: 5, value: self.period)
-        try writer.writeUnknownFields(unknownFields)
+    public func encode(to protoWriter: Wire.ProtoWriter) throws {
+        try protoWriter.encode(tag: 1, value: self.name)
+        try protoWriter.encode(tag: 2, value: self.picture_urls)
+        try protoWriter.encode(tag: 3, value: self.length_meters)
+        try protoWriter.encode(tag: 4, value: self.mass_kilograms)
+        try protoWriter.encode(tag: 5, value: self.period)
+        try protoWriter.writeUnknownFields(unknownFields)
     }
 
 }
@@ -674,17 +678,17 @@ extension Dinosaur : Proto2Codable {
 #if !WIRE_REMOVE_CODABLE
 extension Dinosaur : Codable {
 
-    public init(from decoder: Decoder) throws {
-        let container = try decoder.container(keyedBy: StringLiteralCodingKeys.self)
-        self.name = try container.decodeIfPresent(String.self, forKey: "name")
-        self.picture_urls = try container.decodeProtoArray(String.self, firstOfKeys: "pictureUrls", "picture_urls")
-        self.length_meters = try container.decodeIfPresent(Double.self, firstOfKeys: "lengthMeters", "length_meters")
-        self.mass_kilograms = try container.decodeIfPresent(Double.self, firstOfKeys: "massKilograms", "mass_kilograms")
+    public init(from decoder: Swift.Decoder) throws {
+        let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
+        self._name.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "name")
+        self.picture_urls = try container.decodeProtoArray(Swift.String.self, firstOfKeys: "pictureUrls", "picture_urls")
+        self._length_meters.wrappedValue = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "lengthMeters", "length_meters")
+        self._mass_kilograms.wrappedValue = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "massKilograms", "mass_kilograms")
         self.period = try container.decodeIfPresent(Period.self, forKey: "period")
     }
 
-    public func encode(to encoder: Encoder) throws {
-        var container = encoder.container(keyedBy: StringLiteralCodingKeys.self)
+    public func encode(to encoder: Swift.Encoder) throws {
+        var container = encoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
         let preferCamelCase = encoder.protoKeyNameEncodingStrategy == .camelCase
         let includeDefaults = encoder.protoDefaultValuesEncodingStrategy == .include
 
diff --git a/wire-runtime-swift/src/main/swift/Redactable.swift b/wire-runtime-swift/src/main/swift/Redactable.swift
index eec8967531..06f0716ebc 100644
--- a/wire-runtime-swift/src/main/swift/Redactable.swift
+++ b/wire-runtime-swift/src/main/swift/Redactable.swift
@@ -44,16 +44,20 @@ extension Redactable {
             guard let label = label else {
                 return "\(value)"
             }
-            if RedactedKeys(rawValue: label) != nil {
+            var strippedLabel = label
+            if (label.hasPrefix("_")) {
+                strippedLabel = String(label.dropFirst(1))
+            }
+            if RedactedKeys(rawValue: strippedLabel) != nil {
                 // This is a redacted field, but if it's nil then that's ok to print
                 if "\(value)" != "nil" {
-                    return "\(label): <redacted>"
+                    return "\(strippedLabel): <redacted>"
                 }
             }
             if value is String {
-                return "\(label): \"\(value)\""
+                return "\(strippedLabel): \"\(value)\""
             }
-            return "\(label): \(value)"
+            return "\(strippedLabel): \(value)"
         }
 
         if fields.count > 0 {
diff --git a/wire-runtime-swift/src/test/swift/sample/Dinosaur.swift b/wire-runtime-swift/src/test/swift/sample/Dinosaur.swift
index 385bc3960d..23cfa205ed 100644
--- a/wire-runtime-swift/src/test/swift/sample/Dinosaur.swift
+++ b/wire-runtime-swift/src/test/swift/sample/Dinosaur.swift
@@ -8,12 +8,15 @@ public struct Dinosaur {
     /**
      * Common name of this dinosaur, like "Stegosaurus".
      */
+    @Defaulted(defaultValue: "")
     public var name: String?
     /**
      * URLs with images of this dinosaur.
      */
     public var picture_urls: [String] = []
+    @Defaulted(defaultValue: 0)
     public var length_meters: Double?
+    @Defaulted(defaultValue: 0)
     public var mass_kilograms: Double?
     public var period: Period?
     public var unknownFields: Foundation.Data = .init()
@@ -36,10 +39,10 @@ extension Dinosaur {
         mass_kilograms: Swift.Double? = nil,
         period: Period? = nil
     ) {
-        self.name = name
+        self._name.wrappedValue = name
         self.picture_urls = picture_urls
-        self.length_meters = length_meters
-        self.mass_kilograms = mass_kilograms
+        self._length_meters.wrappedValue = length_meters
+        self._mass_kilograms.wrappedValue = mass_kilograms
         self.period = period
     }
 
@@ -91,10 +94,10 @@ extension Dinosaur : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.name = name
+        self._name.wrappedValue = name
         self.picture_urls = picture_urls
-        self.length_meters = length_meters
-        self.mass_kilograms = mass_kilograms
+        self._length_meters.wrappedValue = length_meters
+        self._mass_kilograms.wrappedValue = mass_kilograms
         self.period = period
     }
 
@@ -114,10 +117,10 @@ extension Dinosaur : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.name = try container.decodeIfPresent(Swift.String.self, forKey: "name")
+        self._name.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "name")
         self.picture_urls = try container.decodeProtoArray(Swift.String.self, firstOfKeys: "pictureUrls", "picture_urls")
-        self.length_meters = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "lengthMeters", "length_meters")
-        self.mass_kilograms = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "massKilograms", "mass_kilograms")
+        self._length_meters.wrappedValue = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "lengthMeters", "length_meters")
+        self._mass_kilograms.wrappedValue = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "massKilograms", "mass_kilograms")
         self.period = try container.decodeIfPresent(Period.self, forKey: "period")
     }
 
diff --git a/wire-swift-generator/src/main/java/com/squareup/wire/swift/SwiftGenerator.kt b/wire-swift-generator/src/main/java/com/squareup/wire/swift/SwiftGenerator.kt
index dc2ceaedad..9648fe48f8 100644
--- a/wire-swift-generator/src/main/java/com/squareup/wire/swift/SwiftGenerator.kt
+++ b/wire-swift-generator/src/main/java/com/squareup/wire/swift/SwiftGenerator.kt
@@ -158,6 +158,40 @@ class SwiftGenerator private constructor(
       else -> null
     }
 
+  private val Field.defaultedValue: CodeBlock?
+    get() {
+      when (val default = default) {
+        // identity values
+        null -> {
+          if (!isOptional) return null
+          if (type == ProtoType.ANY) return null
+          if (isMessage && !isRequiredParameter && !isCollection) {
+            val messageType = schema.getType(type!!) as MessageType
+            return if (messageType.fields.isEmpty() || messageType.fields.any { it.isRequiredParameter }) null else CodeBlock.of("%T()", messageType.typeName.makeNonOptional())
+          }
+          if (isEnum) {
+            val enumType = schema.getType(type!!) as EnumType
+            return if (enumType.constants.firstOrNull { it.tag == 0 } != null) CodeBlock.of("%T.%L", typeName.makeNonOptional(), enumType.constants[0].name) else null
+          }
+          when (typeName.makeNonOptional()) {
+            BOOL -> return CodeBlock.of("%L", false)
+            INT -> return CodeBlock.of("%L", 0)
+            INT32 -> return CodeBlock.of("%L", 0)
+            INT64 -> return CodeBlock.of("%L", 0)
+            UINT32 -> return CodeBlock.of("%L", 0)
+            UINT64 -> return CodeBlock.of("%L", 0)
+            FLOAT -> return CodeBlock.of("%L", 0)
+            DOUBLE -> return CodeBlock.of("%L", 0)
+            STRING -> return CodeBlock.of("%S", "")
+            DATA -> return CodeBlock.of("%T()", DATA)
+          }
+        }
+        else -> return defaultFieldInitializer(type!!, default)
+      }
+
+      return null
+    }
+
   // see https://protobuf.dev/programming-guides/proto3/#default
   private val Field.proto3InitialValue: String
     get() = when {
@@ -651,7 +685,7 @@ class SwiftGenerator private constructor(
               }
             }
             addStatement(
-              if (field.default != null) "_%N.wrappedValue = %L" else { "self.%N = %L" },
+              if (!isIndirect(type, field) && field.defaultedValue != null) "self._%N.wrappedValue = %L" else { "self.%N = %L" },
               field.name,
               initializer,
             )
@@ -831,7 +865,7 @@ class SwiftGenerator private constructor(
                     .map { CodeBlock.of("%S", it) }
                     .joinToCode()
 
-                  val prefix = if (field.default != null) { "_%1N.wrappedValue" } else { "self.%1N" }
+                  val prefix = if (!isIndirect(type, field) && field.defaultedValue != null) { "self._%1N.wrappedValue" } else { "self.%1N" }
                   addStatement(
                     "$prefix = try container.$decode($typeArg%2T.self, $forKeys: $keys)",
                     field.name,
@@ -1146,7 +1180,7 @@ class SwiftGenerator private constructor(
         .apply {
           type.fields.filter { it.isRequiredParameter }.forEach { field ->
             addStatement(
-              if (field.default != null) "_%1N.wrappedValue = %1N" else { "self.%1N = %1N" },
+              if (!isIndirect(type, field) && field.defaultedValue != null) "self._%1N.wrappedValue = %1N" else { "self.%1N = %1N" },
               field.name,
             )
           }
@@ -1172,7 +1206,7 @@ class SwiftGenerator private constructor(
           .apply {
             type.fields.forEach { field ->
               addStatement(
-                if (field.default != null) "_%1N.wrappedValue = %1N" else { "self.%1N = %1N" },
+                if (!isIndirect(type, field) && field.defaultedValue != null) "self._%1N.wrappedValue = %1N" else { "self.%1N = %1N" },
                 field.name,
               )
             }
@@ -1224,10 +1258,9 @@ class SwiftGenerator private constructor(
       if (isIndirect(type, field)) {
         property.addAttribute(AttributeSpec.builder(indirect).build())
       }
-      val default = field.default
-      if (default != null) {
-        val defaultValue = defaultFieldInitializer(field.type!!, default)
-        property.addAttribute(AttributeSpec.builder(defaulted).addArgument("defaultValue: $defaultValue").build())
+      val defaultedValue = field.defaultedValue
+      if (!isIndirect(type, field) && defaultedValue != null) {
+        property.addAttribute(AttributeSpec.builder(defaulted).addArgument("defaultValue: $defaultedValue").build())
       }
 
       if (field.isMap) {
@@ -1278,7 +1311,8 @@ class SwiftGenerator private constructor(
       typeName == DOUBLE -> defaultValue.toDoubleFieldInitializer()
       typeName == STRING -> CodeBlock.of("%S", stringLiteralWithQuotes2(defaultValue.toString()))
       typeName == DATA -> CodeBlock.of(
-        "Foundation.Data(base64Encoded: %S)!",
+        "%T(base64Encoded: %S)!",
+        FOUNDATION_DATA,
         defaultValue.toString().encode(charset = Charsets.ISO_8859_1).base64(),
       )
       protoType.isEnum -> CodeBlock.of("%T.%L", typeName, defaultValue)
diff --git a/wire-tests-swift/manifest/module_three/SwiftModuleThreeMessage.swift b/wire-tests-swift/manifest/module_three/SwiftModuleThreeMessage.swift
index 2b4148a284..4b3fbd9208 100644
--- a/wire-tests-swift/manifest/module_three/SwiftModuleThreeMessage.swift
+++ b/wire-tests-swift/manifest/module_three/SwiftModuleThreeMessage.swift
@@ -6,6 +6,7 @@ import module_one
 
 public struct SwiftModuleThreeMessage {
 
+    @Defaulted(defaultValue: "")
     public var name: String?
     public var unknownFields: Foundation.Data = .init()
 
@@ -21,7 +22,7 @@ extension SwiftModuleThreeMessage {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(name: Swift.String? = nil) {
-        self.name = name
+        self._name.wrappedValue = name
     }
 
 }
@@ -64,7 +65,7 @@ extension SwiftModuleThreeMessage : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.name = name
+        self._name.wrappedValue = name
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -79,7 +80,7 @@ extension SwiftModuleThreeMessage : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.name = try container.decodeIfPresent(Swift.String.self, forKey: "name")
+        self._name.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "name")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/manifest/module_two/SwiftModuleTwoMessage.swift b/wire-tests-swift/manifest/module_two/SwiftModuleTwoMessage.swift
index bcf34c5ad6..178fe51c92 100644
--- a/wire-tests-swift/manifest/module_two/SwiftModuleTwoMessage.swift
+++ b/wire-tests-swift/manifest/module_two/SwiftModuleTwoMessage.swift
@@ -6,6 +6,7 @@ import module_one
 
 public struct SwiftModuleTwoMessage {
 
+    @Defaulted(defaultValue: "")
     public var name: String?
     public var unknownFields: Foundation.Data = .init()
 
@@ -21,7 +22,7 @@ extension SwiftModuleTwoMessage {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(name: Swift.String? = nil) {
-        self.name = name
+        self._name.wrappedValue = name
     }
 
 }
@@ -64,7 +65,7 @@ extension SwiftModuleTwoMessage : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.name = name
+        self._name.wrappedValue = name
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -79,7 +80,7 @@ extension SwiftModuleTwoMessage : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.name = try container.decodeIfPresent(Swift.String.self, forKey: "name")
+        self._name.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "name")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/AllTypes.swift b/wire-tests-swift/no-manifest/src/main/swift/AllTypes.swift
index 600361c18a..19245c70bf 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/AllTypes.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/AllTypes.swift
@@ -1600,6 +1600,7 @@ extension AllTypes {
 
     public struct NestedMessage {
 
+        @Wire.Defaulted(defaultValue: 0)
         public var a: Swift.Int32?
         public var unknownFields: Foundation.Data = .init()
 
@@ -1622,7 +1623,7 @@ extension AllTypes.NestedMessage {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(a: Swift.Int32? = nil) {
-        self.a = a
+        self._a.wrappedValue = a
     }
 
 }
@@ -1665,7 +1666,7 @@ extension AllTypes.NestedMessage : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.a = a
+        self._a.wrappedValue = a
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -1680,7 +1681,7 @@ extension AllTypes.NestedMessage : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.a = try container.decodeIfPresent(Swift.Int32.self, forKey: "a")
+        self._a.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, forKey: "a")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
@@ -1844,23 +1845,23 @@ extension AllTypes.Storage {
         ext_pack_double: [Swift.Double],
         ext_pack_nested_enum: [AllTypes.NestedEnum]
     ) {
-        self.opt_int32 = opt_int32
-        self.opt_uint32 = opt_uint32
-        self.opt_sint32 = opt_sint32
-        self.opt_fixed32 = opt_fixed32
-        self.opt_sfixed32 = opt_sfixed32
-        self.opt_int64 = opt_int64
-        self.opt_uint64 = opt_uint64
-        self.opt_sint64 = opt_sint64
-        self.opt_fixed64 = opt_fixed64
-        self.opt_sfixed64 = opt_sfixed64
-        self.opt_bool = opt_bool
-        self.opt_float = opt_float
-        self.opt_double = opt_double
-        self.opt_string = opt_string
-        self.opt_bytes = opt_bytes
-        self.opt_nested_enum = opt_nested_enum
-        self.opt_nested_message = opt_nested_message
+        self._opt_int32.wrappedValue = opt_int32
+        self._opt_uint32.wrappedValue = opt_uint32
+        self._opt_sint32.wrappedValue = opt_sint32
+        self._opt_fixed32.wrappedValue = opt_fixed32
+        self._opt_sfixed32.wrappedValue = opt_sfixed32
+        self._opt_int64.wrappedValue = opt_int64
+        self._opt_uint64.wrappedValue = opt_uint64
+        self._opt_sint64.wrappedValue = opt_sint64
+        self._opt_fixed64.wrappedValue = opt_fixed64
+        self._opt_sfixed64.wrappedValue = opt_sfixed64
+        self._opt_bool.wrappedValue = opt_bool
+        self._opt_float.wrappedValue = opt_float
+        self._opt_double.wrappedValue = opt_double
+        self._opt_string.wrappedValue = opt_string
+        self._opt_bytes.wrappedValue = opt_bytes
+        self._opt_nested_enum.wrappedValue = opt_nested_enum
+        self._opt_nested_message.wrappedValue = opt_nested_message
         self.req_int32 = req_int32
         self.req_uint32 = req_uint32
         self.req_sint32 = req_sint32
@@ -1909,22 +1910,22 @@ extension AllTypes.Storage {
         self.pack_float = pack_float
         self.pack_double = pack_double
         self.pack_nested_enum = pack_nested_enum
-        _default_int32.wrappedValue = default_int32
-        _default_uint32.wrappedValue = default_uint32
-        _default_sint32.wrappedValue = default_sint32
-        _default_fixed32.wrappedValue = default_fixed32
-        _default_sfixed32.wrappedValue = default_sfixed32
-        _default_int64.wrappedValue = default_int64
-        _default_uint64.wrappedValue = default_uint64
-        _default_sint64.wrappedValue = default_sint64
-        _default_fixed64.wrappedValue = default_fixed64
-        _default_sfixed64.wrappedValue = default_sfixed64
-        _default_bool.wrappedValue = default_bool
-        _default_float.wrappedValue = default_float
-        _default_double.wrappedValue = default_double
-        _default_string.wrappedValue = default_string
-        _default_bytes.wrappedValue = default_bytes
-        _default_nested_enum.wrappedValue = default_nested_enum
+        self._default_int32.wrappedValue = default_int32
+        self._default_uint32.wrappedValue = default_uint32
+        self._default_sint32.wrappedValue = default_sint32
+        self._default_fixed32.wrappedValue = default_fixed32
+        self._default_sfixed32.wrappedValue = default_sfixed32
+        self._default_int64.wrappedValue = default_int64
+        self._default_uint64.wrappedValue = default_uint64
+        self._default_sint64.wrappedValue = default_sint64
+        self._default_fixed64.wrappedValue = default_fixed64
+        self._default_sfixed64.wrappedValue = default_sfixed64
+        self._default_bool.wrappedValue = default_bool
+        self._default_float.wrappedValue = default_float
+        self._default_double.wrappedValue = default_double
+        self._default_string.wrappedValue = default_string
+        self._default_bytes.wrappedValue = default_bytes
+        self._default_nested_enum.wrappedValue = default_nested_enum
         self.map_int32_int32 = map_int32_int32
         self.map_string_string = map_string_string
         self.map_string_message = map_string_message
@@ -1941,23 +1942,23 @@ extension AllTypes.Storage {
         self.array_sfixed64 = array_sfixed64
         self.array_float = array_float
         self.array_double = array_double
-        self.ext_opt_int32 = ext_opt_int32
-        self.ext_opt_uint32 = ext_opt_uint32
-        self.ext_opt_sint32 = ext_opt_sint32
-        self.ext_opt_fixed32 = ext_opt_fixed32
-        self.ext_opt_sfixed32 = ext_opt_sfixed32
-        self.ext_opt_int64 = ext_opt_int64
-        self.ext_opt_uint64 = ext_opt_uint64
-        self.ext_opt_sint64 = ext_opt_sint64
-        self.ext_opt_fixed64 = ext_opt_fixed64
-        self.ext_opt_sfixed64 = ext_opt_sfixed64
-        self.ext_opt_bool = ext_opt_bool
-        self.ext_opt_float = ext_opt_float
-        self.ext_opt_double = ext_opt_double
-        self.ext_opt_string = ext_opt_string
-        self.ext_opt_bytes = ext_opt_bytes
-        self.ext_opt_nested_enum = ext_opt_nested_enum
-        self.ext_opt_nested_message = ext_opt_nested_message
+        self._ext_opt_int32.wrappedValue = ext_opt_int32
+        self._ext_opt_uint32.wrappedValue = ext_opt_uint32
+        self._ext_opt_sint32.wrappedValue = ext_opt_sint32
+        self._ext_opt_fixed32.wrappedValue = ext_opt_fixed32
+        self._ext_opt_sfixed32.wrappedValue = ext_opt_sfixed32
+        self._ext_opt_int64.wrappedValue = ext_opt_int64
+        self._ext_opt_uint64.wrappedValue = ext_opt_uint64
+        self._ext_opt_sint64.wrappedValue = ext_opt_sint64
+        self._ext_opt_fixed64.wrappedValue = ext_opt_fixed64
+        self._ext_opt_sfixed64.wrappedValue = ext_opt_sfixed64
+        self._ext_opt_bool.wrappedValue = ext_opt_bool
+        self._ext_opt_float.wrappedValue = ext_opt_float
+        self._ext_opt_double.wrappedValue = ext_opt_double
+        self._ext_opt_string.wrappedValue = ext_opt_string
+        self._ext_opt_bytes.wrappedValue = ext_opt_bytes
+        self._ext_opt_nested_enum.wrappedValue = ext_opt_nested_enum
+        self._ext_opt_nested_message.wrappedValue = ext_opt_nested_message
         self.ext_rep_int32 = ext_rep_int32
         self.ext_rep_uint32 = ext_rep_uint32
         self.ext_rep_sint32 = ext_rep_sint32
@@ -2001,22 +2002,39 @@ extension AllTypes {
      */
     public struct Storage {
 
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_int32: Swift.Int32?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_uint32: Swift.UInt32?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_sint32: Swift.Int32?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_fixed32: Swift.UInt32?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_sfixed32: Swift.Int32?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_int64: Swift.Int64?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_uint64: Swift.UInt64?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_sint64: Swift.Int64?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_fixed64: Swift.UInt64?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_sfixed64: Swift.Int64?
+        @Wire.Defaulted(defaultValue: false)
         public var opt_bool: Swift.Bool?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_float: Swift.Float?
+        @Wire.Defaulted(defaultValue: 0)
         public var opt_double: Swift.Double?
+        @Wire.Defaulted(defaultValue: "")
         public var opt_string: Swift.String?
+        @Wire.Defaulted(defaultValue: Foundation.Data())
         public var opt_bytes: Foundation.Data?
+        @Wire.Defaulted(defaultValue: AllTypes.NestedEnum.UNKNOWN)
         public var opt_nested_enum: AllTypes.NestedEnum?
+        @Wire.Defaulted(defaultValue: AllTypes.NestedMessage())
         public var opt_nested_message: AllTypes.NestedMessage?
         public var req_int32: Swift.Int32
         public var req_uint32: Swift.UInt32
@@ -2114,22 +2132,39 @@ extension AllTypes {
         public var array_sfixed64: [Swift.Int64] = []
         public var array_float: [Swift.Float] = []
         public var array_double: [Swift.Double] = []
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_int32: Swift.Int32?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_uint32: Swift.UInt32?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_sint32: Swift.Int32?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_fixed32: Swift.UInt32?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_sfixed32: Swift.Int32?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_int64: Swift.Int64?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_uint64: Swift.UInt64?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_sint64: Swift.Int64?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_fixed64: Swift.UInt64?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_sfixed64: Swift.Int64?
+        @Wire.Defaulted(defaultValue: false)
         public var ext_opt_bool: Swift.Bool?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_float: Swift.Float?
+        @Wire.Defaulted(defaultValue: 0)
         public var ext_opt_double: Swift.Double?
+        @Wire.Defaulted(defaultValue: "")
         public var ext_opt_string: Swift.String?
+        @Wire.Defaulted(defaultValue: Foundation.Data())
         public var ext_opt_bytes: Foundation.Data?
+        @Wire.Defaulted(defaultValue: AllTypes.NestedEnum.UNKNOWN)
         public var ext_opt_nested_enum: AllTypes.NestedEnum?
+        @Wire.Defaulted(defaultValue: AllTypes.NestedMessage())
         public var ext_opt_nested_message: AllTypes.NestedMessage?
         public var ext_rep_int32: [Swift.Int32] = []
         public var ext_rep_uint32: [Swift.UInt32] = []
@@ -2533,23 +2568,23 @@ extension AllTypes.Storage : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.opt_int32 = opt_int32
-        self.opt_uint32 = opt_uint32
-        self.opt_sint32 = opt_sint32
-        self.opt_fixed32 = opt_fixed32
-        self.opt_sfixed32 = opt_sfixed32
-        self.opt_int64 = opt_int64
-        self.opt_uint64 = opt_uint64
-        self.opt_sint64 = opt_sint64
-        self.opt_fixed64 = opt_fixed64
-        self.opt_sfixed64 = opt_sfixed64
-        self.opt_bool = opt_bool
-        self.opt_float = opt_float
-        self.opt_double = opt_double
-        self.opt_string = opt_string
-        self.opt_bytes = opt_bytes
-        self.opt_nested_enum = opt_nested_enum
-        self.opt_nested_message = opt_nested_message
+        self._opt_int32.wrappedValue = opt_int32
+        self._opt_uint32.wrappedValue = opt_uint32
+        self._opt_sint32.wrappedValue = opt_sint32
+        self._opt_fixed32.wrappedValue = opt_fixed32
+        self._opt_sfixed32.wrappedValue = opt_sfixed32
+        self._opt_int64.wrappedValue = opt_int64
+        self._opt_uint64.wrappedValue = opt_uint64
+        self._opt_sint64.wrappedValue = opt_sint64
+        self._opt_fixed64.wrappedValue = opt_fixed64
+        self._opt_sfixed64.wrappedValue = opt_sfixed64
+        self._opt_bool.wrappedValue = opt_bool
+        self._opt_float.wrappedValue = opt_float
+        self._opt_double.wrappedValue = opt_double
+        self._opt_string.wrappedValue = opt_string
+        self._opt_bytes.wrappedValue = opt_bytes
+        self._opt_nested_enum.wrappedValue = opt_nested_enum
+        self._opt_nested_message.wrappedValue = opt_nested_message
         self.req_int32 = try AllTypes.checkIfMissing(req_int32, "req_int32")
         self.req_uint32 = try AllTypes.checkIfMissing(req_uint32, "req_uint32")
         self.req_sint32 = try AllTypes.checkIfMissing(req_sint32, "req_sint32")
@@ -2598,22 +2633,22 @@ extension AllTypes.Storage : Proto2Codable {
         self.pack_float = pack_float
         self.pack_double = pack_double
         self.pack_nested_enum = pack_nested_enum
-        _default_int32.wrappedValue = default_int32
-        _default_uint32.wrappedValue = default_uint32
-        _default_sint32.wrappedValue = default_sint32
-        _default_fixed32.wrappedValue = default_fixed32
-        _default_sfixed32.wrappedValue = default_sfixed32
-        _default_int64.wrappedValue = default_int64
-        _default_uint64.wrappedValue = default_uint64
-        _default_sint64.wrappedValue = default_sint64
-        _default_fixed64.wrappedValue = default_fixed64
-        _default_sfixed64.wrappedValue = default_sfixed64
-        _default_bool.wrappedValue = default_bool
-        _default_float.wrappedValue = default_float
-        _default_double.wrappedValue = default_double
-        _default_string.wrappedValue = default_string
-        _default_bytes.wrappedValue = default_bytes
-        _default_nested_enum.wrappedValue = default_nested_enum
+        self._default_int32.wrappedValue = default_int32
+        self._default_uint32.wrappedValue = default_uint32
+        self._default_sint32.wrappedValue = default_sint32
+        self._default_fixed32.wrappedValue = default_fixed32
+        self._default_sfixed32.wrappedValue = default_sfixed32
+        self._default_int64.wrappedValue = default_int64
+        self._default_uint64.wrappedValue = default_uint64
+        self._default_sint64.wrappedValue = default_sint64
+        self._default_fixed64.wrappedValue = default_fixed64
+        self._default_sfixed64.wrappedValue = default_sfixed64
+        self._default_bool.wrappedValue = default_bool
+        self._default_float.wrappedValue = default_float
+        self._default_double.wrappedValue = default_double
+        self._default_string.wrappedValue = default_string
+        self._default_bytes.wrappedValue = default_bytes
+        self._default_nested_enum.wrappedValue = default_nested_enum
         self.map_int32_int32 = map_int32_int32
         self.map_string_string = map_string_string
         self.map_string_message = map_string_message
@@ -2630,23 +2665,23 @@ extension AllTypes.Storage : Proto2Codable {
         self.array_sfixed64 = array_sfixed64
         self.array_float = array_float
         self.array_double = array_double
-        self.ext_opt_int32 = ext_opt_int32
-        self.ext_opt_uint32 = ext_opt_uint32
-        self.ext_opt_sint32 = ext_opt_sint32
-        self.ext_opt_fixed32 = ext_opt_fixed32
-        self.ext_opt_sfixed32 = ext_opt_sfixed32
-        self.ext_opt_int64 = ext_opt_int64
-        self.ext_opt_uint64 = ext_opt_uint64
-        self.ext_opt_sint64 = ext_opt_sint64
-        self.ext_opt_fixed64 = ext_opt_fixed64
-        self.ext_opt_sfixed64 = ext_opt_sfixed64
-        self.ext_opt_bool = ext_opt_bool
-        self.ext_opt_float = ext_opt_float
-        self.ext_opt_double = ext_opt_double
-        self.ext_opt_string = ext_opt_string
-        self.ext_opt_bytes = ext_opt_bytes
-        self.ext_opt_nested_enum = ext_opt_nested_enum
-        self.ext_opt_nested_message = ext_opt_nested_message
+        self._ext_opt_int32.wrappedValue = ext_opt_int32
+        self._ext_opt_uint32.wrappedValue = ext_opt_uint32
+        self._ext_opt_sint32.wrappedValue = ext_opt_sint32
+        self._ext_opt_fixed32.wrappedValue = ext_opt_fixed32
+        self._ext_opt_sfixed32.wrappedValue = ext_opt_sfixed32
+        self._ext_opt_int64.wrappedValue = ext_opt_int64
+        self._ext_opt_uint64.wrappedValue = ext_opt_uint64
+        self._ext_opt_sint64.wrappedValue = ext_opt_sint64
+        self._ext_opt_fixed64.wrappedValue = ext_opt_fixed64
+        self._ext_opt_sfixed64.wrappedValue = ext_opt_sfixed64
+        self._ext_opt_bool.wrappedValue = ext_opt_bool
+        self._ext_opt_float.wrappedValue = ext_opt_float
+        self._ext_opt_double.wrappedValue = ext_opt_double
+        self._ext_opt_string.wrappedValue = ext_opt_string
+        self._ext_opt_bytes.wrappedValue = ext_opt_bytes
+        self._ext_opt_nested_enum.wrappedValue = ext_opt_nested_enum
+        self._ext_opt_nested_message.wrappedValue = ext_opt_nested_message
         self.ext_rep_int32 = ext_rep_int32
         self.ext_rep_uint32 = ext_rep_uint32
         self.ext_rep_sint32 = ext_rep_sint32
@@ -2836,23 +2871,23 @@ extension AllTypes.Storage : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.opt_int32 = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "optInt32", "opt_int32")
-        self.opt_uint32 = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "optUint32", "opt_uint32")
-        self.opt_sint32 = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "optSint32", "opt_sint32")
-        self.opt_fixed32 = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "optFixed32", "opt_fixed32")
-        self.opt_sfixed32 = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "optSfixed32", "opt_sfixed32")
-        self.opt_int64 = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "optInt64", "opt_int64")
-        self.opt_uint64 = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "optUint64", "opt_uint64")
-        self.opt_sint64 = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "optSint64", "opt_sint64")
-        self.opt_fixed64 = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "optFixed64", "opt_fixed64")
-        self.opt_sfixed64 = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "optSfixed64", "opt_sfixed64")
-        self.opt_bool = try container.decodeIfPresent(Swift.Bool.self, firstOfKeys: "optBool", "opt_bool")
-        self.opt_float = try container.decodeIfPresent(Swift.Float.self, firstOfKeys: "optFloat", "opt_float")
-        self.opt_double = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "optDouble", "opt_double")
-        self.opt_string = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "optString", "opt_string")
-        self.opt_bytes = try container.decodeIfPresent(stringEncoded: Foundation.Data.self, firstOfKeys: "optBytes", "opt_bytes")
-        self.opt_nested_enum = try container.decodeIfPresent(AllTypes.NestedEnum.self, firstOfKeys: "optNestedEnum", "opt_nested_enum")
-        self.opt_nested_message = try container.decodeIfPresent(AllTypes.NestedMessage.self, firstOfKeys: "optNestedMessage", "opt_nested_message")
+        self._opt_int32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "optInt32", "opt_int32")
+        self._opt_uint32.wrappedValue = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "optUint32", "opt_uint32")
+        self._opt_sint32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "optSint32", "opt_sint32")
+        self._opt_fixed32.wrappedValue = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "optFixed32", "opt_fixed32")
+        self._opt_sfixed32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "optSfixed32", "opt_sfixed32")
+        self._opt_int64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "optInt64", "opt_int64")
+        self._opt_uint64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "optUint64", "opt_uint64")
+        self._opt_sint64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "optSint64", "opt_sint64")
+        self._opt_fixed64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "optFixed64", "opt_fixed64")
+        self._opt_sfixed64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "optSfixed64", "opt_sfixed64")
+        self._opt_bool.wrappedValue = try container.decodeIfPresent(Swift.Bool.self, firstOfKeys: "optBool", "opt_bool")
+        self._opt_float.wrappedValue = try container.decodeIfPresent(Swift.Float.self, firstOfKeys: "optFloat", "opt_float")
+        self._opt_double.wrappedValue = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "optDouble", "opt_double")
+        self._opt_string.wrappedValue = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "optString", "opt_string")
+        self._opt_bytes.wrappedValue = try container.decodeIfPresent(stringEncoded: Foundation.Data.self, firstOfKeys: "optBytes", "opt_bytes")
+        self._opt_nested_enum.wrappedValue = try container.decodeIfPresent(AllTypes.NestedEnum.self, firstOfKeys: "optNestedEnum", "opt_nested_enum")
+        self._opt_nested_message.wrappedValue = try container.decodeIfPresent(AllTypes.NestedMessage.self, firstOfKeys: "optNestedMessage", "opt_nested_message")
         self.req_int32 = try container.decode(Swift.Int32.self, firstOfKeys: "reqInt32", "req_int32")
         self.req_uint32 = try container.decode(Swift.UInt32.self, firstOfKeys: "reqUint32", "req_uint32")
         self.req_sint32 = try container.decode(Swift.Int32.self, firstOfKeys: "reqSint32", "req_sint32")
@@ -2901,22 +2936,22 @@ extension AllTypes.Storage : Codable {
         self.pack_float = try container.decodeProtoArray(Swift.Float.self, firstOfKeys: "packFloat", "pack_float")
         self.pack_double = try container.decodeProtoArray(Swift.Double.self, firstOfKeys: "packDouble", "pack_double")
         self.pack_nested_enum = try container.decodeProtoArray(AllTypes.NestedEnum.self, firstOfKeys: "packNestedEnum", "pack_nested_enum")
-        _default_int32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "defaultInt32", "default_int32")
-        _default_uint32.wrappedValue = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "defaultUint32", "default_uint32")
-        _default_sint32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "defaultSint32", "default_sint32")
-        _default_fixed32.wrappedValue = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "defaultFixed32", "default_fixed32")
-        _default_sfixed32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "defaultSfixed32", "default_sfixed32")
-        _default_int64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "defaultInt64", "default_int64")
-        _default_uint64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "defaultUint64", "default_uint64")
-        _default_sint64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "defaultSint64", "default_sint64")
-        _default_fixed64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "defaultFixed64", "default_fixed64")
-        _default_sfixed64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "defaultSfixed64", "default_sfixed64")
-        _default_bool.wrappedValue = try container.decodeIfPresent(Swift.Bool.self, firstOfKeys: "defaultBool", "default_bool")
-        _default_float.wrappedValue = try container.decodeIfPresent(Swift.Float.self, firstOfKeys: "defaultFloat", "default_float")
-        _default_double.wrappedValue = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "defaultDouble", "default_double")
-        _default_string.wrappedValue = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "defaultString", "default_string")
-        _default_bytes.wrappedValue = try container.decodeIfPresent(stringEncoded: Foundation.Data.self, firstOfKeys: "defaultBytes", "default_bytes")
-        _default_nested_enum.wrappedValue = try container.decodeIfPresent(AllTypes.NestedEnum.self, firstOfKeys: "defaultNestedEnum", "default_nested_enum")
+        self._default_int32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "defaultInt32", "default_int32")
+        self._default_uint32.wrappedValue = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "defaultUint32", "default_uint32")
+        self._default_sint32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "defaultSint32", "default_sint32")
+        self._default_fixed32.wrappedValue = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "defaultFixed32", "default_fixed32")
+        self._default_sfixed32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "defaultSfixed32", "default_sfixed32")
+        self._default_int64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "defaultInt64", "default_int64")
+        self._default_uint64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "defaultUint64", "default_uint64")
+        self._default_sint64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "defaultSint64", "default_sint64")
+        self._default_fixed64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "defaultFixed64", "default_fixed64")
+        self._default_sfixed64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "defaultSfixed64", "default_sfixed64")
+        self._default_bool.wrappedValue = try container.decodeIfPresent(Swift.Bool.self, firstOfKeys: "defaultBool", "default_bool")
+        self._default_float.wrappedValue = try container.decodeIfPresent(Swift.Float.self, firstOfKeys: "defaultFloat", "default_float")
+        self._default_double.wrappedValue = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "defaultDouble", "default_double")
+        self._default_string.wrappedValue = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "defaultString", "default_string")
+        self._default_bytes.wrappedValue = try container.decodeIfPresent(stringEncoded: Foundation.Data.self, firstOfKeys: "defaultBytes", "default_bytes")
+        self._default_nested_enum.wrappedValue = try container.decodeIfPresent(AllTypes.NestedEnum.self, firstOfKeys: "defaultNestedEnum", "default_nested_enum")
         self.map_int32_int32 = try container.decodeProtoMap([Swift.Int32 : Swift.Int32].self, firstOfKeys: "mapInt32Int32", "map_int32_int32")
         self.map_string_string = try container.decodeProtoMap([Swift.String : Swift.String].self, firstOfKeys: "mapStringString", "map_string_string")
         self.map_string_message = try container.decodeProtoMap([Swift.String : AllTypes.NestedMessage].self, firstOfKeys: "mapStringMessage", "map_string_message")
@@ -2933,23 +2968,23 @@ extension AllTypes.Storage : Codable {
         self.array_sfixed64 = try container.decodeProtoArray(Swift.Int64.self, firstOfKeys: "arraySfixed64", "array_sfixed64")
         self.array_float = try container.decodeProtoArray(Swift.Float.self, firstOfKeys: "arrayFloat", "array_float")
         self.array_double = try container.decodeProtoArray(Swift.Double.self, firstOfKeys: "arrayDouble", "array_double")
-        self.ext_opt_int32 = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "extOptInt32", "ext_opt_int32")
-        self.ext_opt_uint32 = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "extOptUint32", "ext_opt_uint32")
-        self.ext_opt_sint32 = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "extOptSint32", "ext_opt_sint32")
-        self.ext_opt_fixed32 = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "extOptFixed32", "ext_opt_fixed32")
-        self.ext_opt_sfixed32 = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "extOptSfixed32", "ext_opt_sfixed32")
-        self.ext_opt_int64 = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "extOptInt64", "ext_opt_int64")
-        self.ext_opt_uint64 = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "extOptUint64", "ext_opt_uint64")
-        self.ext_opt_sint64 = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "extOptSint64", "ext_opt_sint64")
-        self.ext_opt_fixed64 = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "extOptFixed64", "ext_opt_fixed64")
-        self.ext_opt_sfixed64 = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "extOptSfixed64", "ext_opt_sfixed64")
-        self.ext_opt_bool = try container.decodeIfPresent(Swift.Bool.self, firstOfKeys: "extOptBool", "ext_opt_bool")
-        self.ext_opt_float = try container.decodeIfPresent(Swift.Float.self, firstOfKeys: "extOptFloat", "ext_opt_float")
-        self.ext_opt_double = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "extOptDouble", "ext_opt_double")
-        self.ext_opt_string = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "extOptString", "ext_opt_string")
-        self.ext_opt_bytes = try container.decodeIfPresent(stringEncoded: Foundation.Data.self, firstOfKeys: "extOptBytes", "ext_opt_bytes")
-        self.ext_opt_nested_enum = try container.decodeIfPresent(AllTypes.NestedEnum.self, firstOfKeys: "extOptNestedEnum", "ext_opt_nested_enum")
-        self.ext_opt_nested_message = try container.decodeIfPresent(AllTypes.NestedMessage.self, firstOfKeys: "extOptNestedMessage", "ext_opt_nested_message")
+        self._ext_opt_int32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "extOptInt32", "ext_opt_int32")
+        self._ext_opt_uint32.wrappedValue = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "extOptUint32", "ext_opt_uint32")
+        self._ext_opt_sint32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "extOptSint32", "ext_opt_sint32")
+        self._ext_opt_fixed32.wrappedValue = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "extOptFixed32", "ext_opt_fixed32")
+        self._ext_opt_sfixed32.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "extOptSfixed32", "ext_opt_sfixed32")
+        self._ext_opt_int64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "extOptInt64", "ext_opt_int64")
+        self._ext_opt_uint64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "extOptUint64", "ext_opt_uint64")
+        self._ext_opt_sint64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "extOptSint64", "ext_opt_sint64")
+        self._ext_opt_fixed64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "extOptFixed64", "ext_opt_fixed64")
+        self._ext_opt_sfixed64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.Int64.self, firstOfKeys: "extOptSfixed64", "ext_opt_sfixed64")
+        self._ext_opt_bool.wrappedValue = try container.decodeIfPresent(Swift.Bool.self, firstOfKeys: "extOptBool", "ext_opt_bool")
+        self._ext_opt_float.wrappedValue = try container.decodeIfPresent(Swift.Float.self, firstOfKeys: "extOptFloat", "ext_opt_float")
+        self._ext_opt_double.wrappedValue = try container.decodeIfPresent(Swift.Double.self, firstOfKeys: "extOptDouble", "ext_opt_double")
+        self._ext_opt_string.wrappedValue = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "extOptString", "ext_opt_string")
+        self._ext_opt_bytes.wrappedValue = try container.decodeIfPresent(stringEncoded: Foundation.Data.self, firstOfKeys: "extOptBytes", "ext_opt_bytes")
+        self._ext_opt_nested_enum.wrappedValue = try container.decodeIfPresent(AllTypes.NestedEnum.self, firstOfKeys: "extOptNestedEnum", "ext_opt_nested_enum")
+        self._ext_opt_nested_message.wrappedValue = try container.decodeIfPresent(AllTypes.NestedMessage.self, firstOfKeys: "extOptNestedMessage", "ext_opt_nested_message")
         self.ext_rep_int32 = try container.decodeProtoArray(Swift.Int32.self, firstOfKeys: "extRepInt32", "ext_rep_int32")
         self.ext_rep_uint32 = try container.decodeProtoArray(Swift.UInt32.self, firstOfKeys: "extRepUint32", "ext_rep_uint32")
         self.ext_rep_sint32 = try container.decodeProtoArray(Swift.Int32.self, firstOfKeys: "extRepSint32", "ext_rep_sint32")
diff --git a/wire-tests-swift/no-manifest/src/main/swift/DeprecatedProto.swift b/wire-tests-swift/no-manifest/src/main/swift/DeprecatedProto.swift
index 37ed4164e7..5621dcbd4b 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/DeprecatedProto.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/DeprecatedProto.swift
@@ -6,6 +6,7 @@ import Wire
 public struct DeprecatedProto {
 
     @available(*, deprecated)
+    @Defaulted(defaultValue: "")
     public var foo: String?
     public var unknownFields: Foundation.Data = .init()
 
@@ -21,7 +22,7 @@ extension DeprecatedProto {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(foo: Swift.String? = nil) {
-        self.foo = foo
+        self._foo.wrappedValue = foo
     }
 
 }
@@ -64,7 +65,7 @@ extension DeprecatedProto : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.foo = foo
+        self._foo.wrappedValue = foo
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -79,7 +80,7 @@ extension DeprecatedProto : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.foo = try container.decodeIfPresent(Swift.String.self, forKey: "foo")
+        self._foo.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "foo")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/EmbeddedMessage.swift b/wire-tests-swift/no-manifest/src/main/swift/EmbeddedMessage.swift
index d1f5e0d533..e99ed802eb 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/EmbeddedMessage.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/EmbeddedMessage.swift
@@ -6,6 +6,7 @@ import Wire
 public struct EmbeddedMessage {
 
     public var inner_repeated_number: [Int32] = []
+    @Defaulted(defaultValue: 0)
     public var inner_number_after: Int32?
     public var unknownFields: Foundation.Data = .init()
 
@@ -22,7 +23,7 @@ extension EmbeddedMessage {
     @available(*, deprecated)
     public init(inner_repeated_number: [Swift.Int32] = [], inner_number_after: Swift.Int32? = nil) {
         self.inner_repeated_number = inner_repeated_number
-        self.inner_number_after = inner_number_after
+        self._inner_number_after.wrappedValue = inner_number_after
     }
 
 }
@@ -68,7 +69,7 @@ extension EmbeddedMessage : Proto2Codable {
         self.unknownFields = try protoReader.endMessage(token: token)
 
         self.inner_repeated_number = inner_repeated_number
-        self.inner_number_after = inner_number_after
+        self._inner_number_after.wrappedValue = inner_number_after
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -85,7 +86,7 @@ extension EmbeddedMessage : Codable {
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
         self.inner_repeated_number = try container.decodeProtoArray(Swift.Int32.self, firstOfKeys: "innerRepeatedNumber", "inner_repeated_number")
-        self.inner_number_after = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "innerNumberAfter", "inner_number_after")
+        self._inner_number_after.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "innerNumberAfter", "inner_number_after")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/ExternalMessage.swift b/wire-tests-swift/no-manifest/src/main/swift/ExternalMessage.swift
index 1f3aafd7f5..47fc12f531 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/ExternalMessage.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/ExternalMessage.swift
@@ -21,7 +21,7 @@ extension ExternalMessage {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(f: Swift.Float? = nil) {
-        _f.wrappedValue = f
+        self._f.wrappedValue = f
     }
 
 }
@@ -64,7 +64,7 @@ extension ExternalMessage : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        _f.wrappedValue = f
+        self._f.wrappedValue = f
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -79,7 +79,7 @@ extension ExternalMessage : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        _f.wrappedValue = try container.decodeIfPresent(Swift.Float.self, forKey: "f")
+        self._f.wrappedValue = try container.decodeIfPresent(Swift.Float.self, forKey: "f")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/FooBar.swift b/wire-tests-swift/no-manifest/src/main/swift/FooBar.swift
index 8affc4d7e1..2d4ed34039 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/FooBar.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/FooBar.swift
@@ -5,15 +5,21 @@ import Wire
 
 public struct FooBar {
 
+    @Defaulted(defaultValue: 0)
     public var foo: Int32?
+    @Defaulted(defaultValue: "")
     public var bar: String?
+    @Defaulted(defaultValue: FooBar.Nested())
     public var baz: FooBar.Nested?
+    @Defaulted(defaultValue: 0)
     public var qux: UInt64?
     public var fred: [Float] = []
+    @Defaulted(defaultValue: 0)
     public var daisy: Double?
     public var nested: [FooBar] = []
     public var ext: FooBar.FooBarBazEnum?
     public var rep: [FooBar.FooBarBazEnum] = []
+    @Defaulted(defaultValue: "")
     public var more_string: String?
     public var unknownFields: Foundation.Data = .init()
 
@@ -40,16 +46,16 @@ extension FooBar {
         rep: [FooBar.FooBarBazEnum] = [],
         more_string: Swift.String? = nil
     ) {
-        self.foo = foo
-        self.bar = bar
-        self.baz = baz
-        self.qux = qux
+        self._foo.wrappedValue = foo
+        self._bar.wrappedValue = bar
+        self._baz.wrappedValue = baz
+        self._qux.wrappedValue = qux
         self.fred = fred
-        self.daisy = daisy
+        self._daisy.wrappedValue = daisy
         self.nested = nested
         self.ext = ext
         self.rep = rep
-        self.more_string = more_string
+        self._more_string.wrappedValue = more_string
     }
 
 }
@@ -122,16 +128,16 @@ extension FooBar : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.foo = foo
-        self.bar = bar
-        self.baz = baz
-        self.qux = qux
+        self._foo.wrappedValue = foo
+        self._bar.wrappedValue = bar
+        self._baz.wrappedValue = baz
+        self._qux.wrappedValue = qux
         self.fred = fred
-        self.daisy = daisy
+        self._daisy.wrappedValue = daisy
         self.nested = nested
         self.ext = ext
         self.rep = rep
-        self.more_string = more_string
+        self._more_string.wrappedValue = more_string
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -155,16 +161,16 @@ extension FooBar : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.foo = try container.decodeIfPresent(Swift.Int32.self, forKey: "foo")
-        self.bar = try container.decodeIfPresent(Swift.String.self, forKey: "bar")
-        self.baz = try container.decodeIfPresent(FooBar.Nested.self, forKey: "baz")
-        self.qux = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, forKey: "qux")
+        self._foo.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, forKey: "foo")
+        self._bar.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "bar")
+        self._baz.wrappedValue = try container.decodeIfPresent(FooBar.Nested.self, forKey: "baz")
+        self._qux.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, forKey: "qux")
         self.fred = try container.decodeProtoArray(Swift.Float.self, forKey: "fred")
-        self.daisy = try container.decodeIfPresent(Swift.Double.self, forKey: "daisy")
+        self._daisy.wrappedValue = try container.decodeIfPresent(Swift.Double.self, forKey: "daisy")
         self.nested = try container.decodeProtoArray(FooBar.self, forKey: "nested")
         self.ext = try container.decodeIfPresent(FooBar.FooBarBazEnum.self, forKey: "ext")
         self.rep = try container.decodeProtoArray(FooBar.FooBarBazEnum.self, forKey: "rep")
-        self.more_string = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "moreString", "more_string")
+        self._more_string.wrappedValue = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "moreString", "more_string")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/ForeignMessage.swift b/wire-tests-swift/no-manifest/src/main/swift/ForeignMessage.swift
index 3822573d79..aa6de1ea5f 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/ForeignMessage.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/ForeignMessage.swift
@@ -5,6 +5,7 @@ import Wire
 
 public struct ForeignMessage {
 
+    @Defaulted(defaultValue: 0)
     public var i: Int32?
     public var unknownFields: Foundation.Data = .init()
 
@@ -20,7 +21,7 @@ extension ForeignMessage {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(i: Swift.Int32? = nil) {
-        self.i = i
+        self._i.wrappedValue = i
     }
 
 }
@@ -63,7 +64,7 @@ extension ForeignMessage : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.i = i
+        self._i.wrappedValue = i
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -78,7 +79,7 @@ extension ForeignMessage : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.i = try container.decodeIfPresent(Swift.Int32.self, forKey: "i")
+        self._i.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, forKey: "i")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/Form.swift b/wire-tests-swift/no-manifest/src/main/swift/Form.swift
index f2a1f3e039..299d211c81 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/Form.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/Form.swift
@@ -326,6 +326,7 @@ extension Form {
 
     public struct TextElement {
 
+        @Wire.Defaulted(defaultValue: "")
         public var text: Swift.String?
         public var unknownFields: Foundation.Data = .init()
 
@@ -694,7 +695,7 @@ extension Form.TextElement {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(text: Swift.String? = nil) {
-        self.text = text
+        self._text.wrappedValue = text
     }
 
 }
@@ -737,7 +738,7 @@ extension Form.TextElement : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.text = text
+        self._text.wrappedValue = text
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -752,7 +753,7 @@ extension Form.TextElement : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.text = try container.decodeIfPresent(Swift.String.self, forKey: "text")
+        self._text.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "text")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/ModelEvaluation.swift b/wire-tests-swift/no-manifest/src/main/swift/ModelEvaluation.swift
index 4c4524a1d8..1171a8a860 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/ModelEvaluation.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/ModelEvaluation.swift
@@ -20,7 +20,9 @@ import Wire
  */
 public struct ModelEvaluation {
 
+    @Defaulted(defaultValue: "")
     public var name: String?
+    @Defaulted(defaultValue: 0)
     public var score: Double?
     public var models: [String : ModelEvaluation] = [:]
     public var unknownFields: Foundation.Data = .init()
@@ -41,8 +43,8 @@ extension ModelEvaluation {
         score: Swift.Double? = nil,
         models: [Swift.String : ModelEvaluation] = [:]
     ) {
-        self.name = name
-        self.score = score
+        self._name.wrappedValue = name
+        self._score.wrappedValue = score
         self.models = models
     }
 
@@ -90,8 +92,8 @@ extension ModelEvaluation : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.name = name
-        self.score = score
+        self._name.wrappedValue = name
+        self._score.wrappedValue = score
         self.models = models
     }
 
@@ -109,8 +111,8 @@ extension ModelEvaluation : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.name = try container.decodeIfPresent(Swift.String.self, forKey: "name")
-        self.score = try container.decodeIfPresent(Swift.Double.self, forKey: "score")
+        self._name.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "name")
+        self._score.wrappedValue = try container.decodeIfPresent(Swift.Double.self, forKey: "score")
         self.models = try container.decodeProtoMap([Swift.String : ModelEvaluation].self, forKey: "models")
     }
 
diff --git a/wire-tests-swift/no-manifest/src/main/swift/NestedVersionOne.swift b/wire-tests-swift/no-manifest/src/main/swift/NestedVersionOne.swift
index 0d59f3a917..fbc23e6869 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/NestedVersionOne.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/NestedVersionOne.swift
@@ -5,6 +5,7 @@ import Wire
 
 public struct NestedVersionOne {
 
+    @Defaulted(defaultValue: 0)
     public var i: Int32?
     public var unknownFields: Foundation.Data = .init()
 
@@ -20,7 +21,7 @@ extension NestedVersionOne {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(i: Swift.Int32? = nil) {
-        self.i = i
+        self._i.wrappedValue = i
     }
 
 }
@@ -63,7 +64,7 @@ extension NestedVersionOne : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.i = i
+        self._i.wrappedValue = i
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -78,7 +79,7 @@ extension NestedVersionOne : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.i = try container.decodeIfPresent(Swift.Int32.self, forKey: "i")
+        self._i.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, forKey: "i")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/NestedVersionTwo.swift b/wire-tests-swift/no-manifest/src/main/swift/NestedVersionTwo.swift
index 8e4bfbcdfb..6f292ee0aa 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/NestedVersionTwo.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/NestedVersionTwo.swift
@@ -5,10 +5,15 @@ import Wire
 
 public struct NestedVersionTwo {
 
+    @Defaulted(defaultValue: 0)
     public var i: Int32?
+    @Defaulted(defaultValue: 0)
     public var v2_i: Int32?
+    @Defaulted(defaultValue: "")
     public var v2_s: String?
+    @Defaulted(defaultValue: 0)
     public var v2_f32: UInt32?
+    @Defaulted(defaultValue: 0)
     public var v2_f64: UInt64?
     public var v2_rs: [String] = []
     public var unknownFields: Foundation.Data = .init()
@@ -32,11 +37,11 @@ extension NestedVersionTwo {
         v2_f64: Swift.UInt64? = nil,
         v2_rs: [Swift.String] = []
     ) {
-        self.i = i
-        self.v2_i = v2_i
-        self.v2_s = v2_s
-        self.v2_f32 = v2_f32
-        self.v2_f64 = v2_f64
+        self._i.wrappedValue = i
+        self._v2_i.wrappedValue = v2_i
+        self._v2_s.wrappedValue = v2_s
+        self._v2_f32.wrappedValue = v2_f32
+        self._v2_f64.wrappedValue = v2_f64
         self.v2_rs = v2_rs
     }
 
@@ -90,11 +95,11 @@ extension NestedVersionTwo : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.i = i
-        self.v2_i = v2_i
-        self.v2_s = v2_s
-        self.v2_f32 = v2_f32
-        self.v2_f64 = v2_f64
+        self._i.wrappedValue = i
+        self._v2_i.wrappedValue = v2_i
+        self._v2_s.wrappedValue = v2_s
+        self._v2_f32.wrappedValue = v2_f32
+        self._v2_f64.wrappedValue = v2_f64
         self.v2_rs = v2_rs
     }
 
@@ -115,11 +120,11 @@ extension NestedVersionTwo : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.i = try container.decodeIfPresent(Swift.Int32.self, forKey: "i")
-        self.v2_i = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "v2I", "v2_i")
-        self.v2_s = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "v2S", "v2_s")
-        self.v2_f32 = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "v2F32", "v2_f32")
-        self.v2_f64 = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "v2F64", "v2_f64")
+        self._i.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, forKey: "i")
+        self._v2_i.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "v2I", "v2_i")
+        self._v2_s.wrappedValue = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "v2S", "v2_s")
+        self._v2_f32.wrappedValue = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "v2F32", "v2_f32")
+        self._v2_f64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "v2F64", "v2_f64")
         self.v2_rs = try container.decodeProtoArray(Swift.String.self, firstOfKeys: "v2Rs", "v2_rs")
     }
 
diff --git a/wire-tests-swift/no-manifest/src/main/swift/OuterMessage.swift b/wire-tests-swift/no-manifest/src/main/swift/OuterMessage.swift
index 5a1c1d0b73..8bca3c46ce 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/OuterMessage.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/OuterMessage.swift
@@ -5,7 +5,9 @@ import Wire
 
 public struct OuterMessage {
 
+    @Defaulted(defaultValue: 0)
     public var outer_number_before: Int32?
+    @Defaulted(defaultValue: EmbeddedMessage())
     public var embedded_message: EmbeddedMessage?
     public var unknownFields: Foundation.Data = .init()
 
@@ -21,8 +23,8 @@ extension OuterMessage {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(outer_number_before: Swift.Int32? = nil, embedded_message: EmbeddedMessage? = nil) {
-        self.outer_number_before = outer_number_before
-        self.embedded_message = embedded_message
+        self._outer_number_before.wrappedValue = outer_number_before
+        self._embedded_message.wrappedValue = embedded_message
     }
 
 }
@@ -67,8 +69,8 @@ extension OuterMessage : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.outer_number_before = outer_number_before
-        self.embedded_message = embedded_message
+        self._outer_number_before.wrappedValue = outer_number_before
+        self._embedded_message.wrappedValue = embedded_message
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -84,8 +86,8 @@ extension OuterMessage : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.outer_number_before = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "outerNumberBefore", "outer_number_before")
-        self.embedded_message = try container.decodeIfPresent(EmbeddedMessage.self, firstOfKeys: "embeddedMessage", "embedded_message")
+        self._outer_number_before.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "outerNumberBefore", "outer_number_before")
+        self._embedded_message.wrappedValue = try container.decodeIfPresent(EmbeddedMessage.self, firstOfKeys: "embeddedMessage", "embedded_message")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/Percents.swift b/wire-tests-swift/no-manifest/src/main/swift/Percents.swift
index 187df1117e..184a809464 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/Percents.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/Percents.swift
@@ -8,6 +8,7 @@ public struct Percents {
     /**
      * e.g. "No limits, free to send and just 2.75% to receive".
      */
+    @Defaulted(defaultValue: "")
     public var text: String?
     public var unknownFields: Foundation.Data = .init()
 
@@ -23,7 +24,7 @@ extension Percents {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(text: Swift.String? = nil) {
-        self.text = text
+        self._text.wrappedValue = text
     }
 
 }
@@ -66,7 +67,7 @@ extension Percents : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.text = text
+        self._text.wrappedValue = text
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -81,7 +82,7 @@ extension Percents : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.text = try container.decodeIfPresent(Swift.String.self, forKey: "text")
+        self._text.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "text")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/Person.swift b/wire-tests-swift/no-manifest/src/main/swift/Person.swift
index 08465f8858..1f418f1741 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/Person.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/Person.swift
@@ -19,6 +19,7 @@ public struct Person {
     /**
      * Email address for the customer.
      */
+    @Defaulted(defaultValue: "")
     public var email: String?
     /**
      * A list of the customer's phone numbers.
@@ -53,7 +54,7 @@ extension Person {
     ) {
         self.id = id
         self.name = name
-        self.email = email
+        self._email.wrappedValue = email
         self.phone = phone
         self.aliases = aliases
     }
@@ -108,7 +109,7 @@ extension Person : Proto2Codable {
 
         self.id = try Person.checkIfMissing(id, "id")
         self.name = try Person.checkIfMissing(name, "name")
-        self.email = email
+        self._email.wrappedValue = email
         self.phone = phone
         self.aliases = aliases
     }
@@ -131,7 +132,7 @@ extension Person : Codable {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
         self.id = try container.decode(Swift.Int32.self, forKey: "id")
         self.name = try container.decode(Swift.String.self, forKey: "name")
-        self.email = try container.decodeIfPresent(Swift.String.self, forKey: "email")
+        self._email.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "email")
         self.phone = try container.decodeProtoArray(Person.PhoneNumber.self, forKey: "phone")
         self.aliases = try container.decodeProtoArray(Swift.String.self, forKey: "aliases")
     }
@@ -219,7 +220,7 @@ extension Person.PhoneNumber {
     @available(*, deprecated)
     public init(number: Swift.String, type: Person.PhoneType? = nil) {
         self.number = number
-        _type.wrappedValue = type
+        self._type.wrappedValue = type
     }
 
 }
@@ -265,7 +266,7 @@ extension Person.PhoneNumber : Proto2Codable {
         self.unknownFields = try protoReader.endMessage(token: token)
 
         self.number = try Person.PhoneNumber.checkIfMissing(number, "number")
-        _type.wrappedValue = type
+        self._type.wrappedValue = type
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -282,7 +283,7 @@ extension Person.PhoneNumber : Codable {
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
         self.number = try container.decode(Swift.String.self, forKey: "number")
-        _type.wrappedValue = try container.decodeIfPresent(Person.PhoneType.self, forKey: "type")
+        self._type.wrappedValue = try container.decodeIfPresent(Person.PhoneType.self, forKey: "type")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/Thing.swift b/wire-tests-swift/no-manifest/src/main/swift/Thing.swift
index 2ee456ed1d..26ef3861f2 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/Thing.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/Thing.swift
@@ -5,6 +5,7 @@ import Wire
 
 public struct Thing {
 
+    @Defaulted(defaultValue: "")
     public var name: String?
     public var unknownFields: Foundation.Data = .init()
 
@@ -20,7 +21,7 @@ extension Thing {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(name: Swift.String? = nil) {
-        self.name = name
+        self._name.wrappedValue = name
     }
 
 }
@@ -63,7 +64,7 @@ extension Thing : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.name = name
+        self._name.wrappedValue = name
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -78,7 +79,7 @@ extension Thing : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.name = try container.decodeIfPresent(Swift.String.self, forKey: "name")
+        self._name.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "name")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {
diff --git a/wire-tests-swift/no-manifest/src/main/swift/VersionOne.swift b/wire-tests-swift/no-manifest/src/main/swift/VersionOne.swift
index af553e8109..e9869d2d28 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/VersionOne.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/VersionOne.swift
@@ -5,7 +5,9 @@ import Wire
 
 public struct VersionOne {
 
+    @Defaulted(defaultValue: 0)
     public var i: Int32?
+    @Defaulted(defaultValue: NestedVersionOne())
     public var obj: NestedVersionOne?
     public var en: EnumVersionOne?
     public var unknownFields: Foundation.Data = .init()
@@ -26,8 +28,8 @@ extension VersionOne {
         obj: NestedVersionOne? = nil,
         en: EnumVersionOne? = nil
     ) {
-        self.i = i
-        self.obj = obj
+        self._i.wrappedValue = i
+        self._obj.wrappedValue = obj
         self.en = en
     }
 
@@ -75,8 +77,8 @@ extension VersionOne : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.i = i
-        self.obj = obj
+        self._i.wrappedValue = i
+        self._obj.wrappedValue = obj
         self.en = en
     }
 
@@ -94,8 +96,8 @@ extension VersionOne : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.i = try container.decodeIfPresent(Swift.Int32.self, forKey: "i")
-        self.obj = try container.decodeIfPresent(NestedVersionOne.self, forKey: "obj")
+        self._i.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, forKey: "i")
+        self._obj.wrappedValue = try container.decodeIfPresent(NestedVersionOne.self, forKey: "obj")
         self.en = try container.decodeIfPresent(EnumVersionOne.self, forKey: "en")
     }
 
diff --git a/wire-tests-swift/no-manifest/src/main/swift/VersionTwo.swift b/wire-tests-swift/no-manifest/src/main/swift/VersionTwo.swift
index 40347c6af3..12fe2d2654 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/VersionTwo.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/VersionTwo.swift
@@ -5,12 +5,18 @@ import Wire
 
 public struct VersionTwo {
 
+    @Defaulted(defaultValue: 0)
     public var i: Int32?
+    @Defaulted(defaultValue: 0)
     public var v2_i: Int32?
+    @Defaulted(defaultValue: "")
     public var v2_s: String?
+    @Defaulted(defaultValue: 0)
     public var v2_f32: UInt32?
+    @Defaulted(defaultValue: 0)
     public var v2_f64: UInt64?
     public var v2_rs: [String] = []
+    @Defaulted(defaultValue: NestedVersionTwo())
     public var obj: NestedVersionTwo?
     public var en: EnumVersionTwo?
     public var unknownFields: Foundation.Data = .init()
@@ -36,13 +42,13 @@ extension VersionTwo {
         obj: NestedVersionTwo? = nil,
         en: EnumVersionTwo? = nil
     ) {
-        self.i = i
-        self.v2_i = v2_i
-        self.v2_s = v2_s
-        self.v2_f32 = v2_f32
-        self.v2_f64 = v2_f64
+        self._i.wrappedValue = i
+        self._v2_i.wrappedValue = v2_i
+        self._v2_s.wrappedValue = v2_s
+        self._v2_f32.wrappedValue = v2_f32
+        self._v2_f64.wrappedValue = v2_f64
         self.v2_rs = v2_rs
-        self.obj = obj
+        self._obj.wrappedValue = obj
         self.en = en
     }
 
@@ -100,13 +106,13 @@ extension VersionTwo : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.i = i
-        self.v2_i = v2_i
-        self.v2_s = v2_s
-        self.v2_f32 = v2_f32
-        self.v2_f64 = v2_f64
+        self._i.wrappedValue = i
+        self._v2_i.wrappedValue = v2_i
+        self._v2_s.wrappedValue = v2_s
+        self._v2_f32.wrappedValue = v2_f32
+        self._v2_f64.wrappedValue = v2_f64
         self.v2_rs = v2_rs
-        self.obj = obj
+        self._obj.wrappedValue = obj
         self.en = en
     }
 
@@ -129,13 +135,13 @@ extension VersionTwo : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.i = try container.decodeIfPresent(Swift.Int32.self, forKey: "i")
-        self.v2_i = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "v2I", "v2_i")
-        self.v2_s = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "v2S", "v2_s")
-        self.v2_f32 = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "v2F32", "v2_f32")
-        self.v2_f64 = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "v2F64", "v2_f64")
+        self._i.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, forKey: "i")
+        self._v2_i.wrappedValue = try container.decodeIfPresent(Swift.Int32.self, firstOfKeys: "v2I", "v2_i")
+        self._v2_s.wrappedValue = try container.decodeIfPresent(Swift.String.self, firstOfKeys: "v2S", "v2_s")
+        self._v2_f32.wrappedValue = try container.decodeIfPresent(Swift.UInt32.self, firstOfKeys: "v2F32", "v2_f32")
+        self._v2_f64.wrappedValue = try container.decodeIfPresent(stringEncoded: Swift.UInt64.self, firstOfKeys: "v2F64", "v2_f64")
         self.v2_rs = try container.decodeProtoArray(Swift.String.self, firstOfKeys: "v2Rs", "v2_rs")
-        self.obj = try container.decodeIfPresent(NestedVersionTwo.self, forKey: "obj")
+        self._obj.wrappedValue = try container.decodeIfPresent(NestedVersionTwo.self, forKey: "obj")
         self.en = try container.decodeIfPresent(EnumVersionTwo.self, forKey: "en")
     }
 
diff --git a/wire-tests-swift/no-manifest/src/main/swift/VeryLongProtoNameCausingBrokenLineBreaks.swift b/wire-tests-swift/no-manifest/src/main/swift/VeryLongProtoNameCausingBrokenLineBreaks.swift
index 3b28de703a..453c9aabc8 100644
--- a/wire-tests-swift/no-manifest/src/main/swift/VeryLongProtoNameCausingBrokenLineBreaks.swift
+++ b/wire-tests-swift/no-manifest/src/main/swift/VeryLongProtoNameCausingBrokenLineBreaks.swift
@@ -8,6 +8,7 @@ import Wire
  */
 public struct VeryLongProtoNameCausingBrokenLineBreaks {
 
+    @Defaulted(defaultValue: "")
     public var foo: String?
     public var unknownFields: Foundation.Data = .init()
 
@@ -23,7 +24,7 @@ extension VeryLongProtoNameCausingBrokenLineBreaks {
     @_disfavoredOverload
     @available(*, deprecated)
     public init(foo: Swift.String? = nil) {
-        self.foo = foo
+        self._foo.wrappedValue = foo
     }
 
 }
@@ -66,7 +67,7 @@ extension VeryLongProtoNameCausingBrokenLineBreaks : Proto2Codable {
         }
         self.unknownFields = try protoReader.endMessage(token: token)
 
-        self.foo = foo
+        self._foo.wrappedValue = foo
     }
 
     public func encode(to protoWriter: Wire.ProtoWriter) throws {
@@ -81,7 +82,7 @@ extension VeryLongProtoNameCausingBrokenLineBreaks : Codable {
 
     public init(from decoder: Swift.Decoder) throws {
         let container = try decoder.container(keyedBy: Wire.StringLiteralCodingKeys.self)
-        self.foo = try container.decodeIfPresent(Swift.String.self, forKey: "foo")
+        self._foo.wrappedValue = try container.decodeIfPresent(Swift.String.self, forKey: "foo")
     }
 
     public func encode(to encoder: Swift.Encoder) throws {