diff --git a/.spi.yml b/.spi.yml
index ff36ee998..4949a4c2c 100644
--- a/.spi.yml
+++ b/.spi.yml
@@ -1,4 +1,4 @@
 version: 1
 builder:
   configs:
-    - documentation_targets: [CodableMacroPlugin, MetaCodable]
\ No newline at end of file
+    - documentation_targets: [MetaCodable, HelperCoders]
\ No newline at end of file
diff --git a/.vscode/settings.json b/.vscode/settings.json
index 844b16b8b..ff96b7538 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -10,4 +10,8 @@
     "editor.unicodeHighlight.allowedCharacters": {
         "－": true
     },
+    "swift.disableAutoResolve": true,
+    "swift.swiftEnvironmentVariables": {
+        "SWIFT_SYNTAX_EXTENSION_MACRO_FIXED": "true"
+    },
 }
\ No newline at end of file
diff --git a/Package.swift b/Package.swift
index 455e41177..0dd554836 100644
--- a/Package.swift
+++ b/Package.swift
@@ -45,3 +45,19 @@ let package = Package(
         ),
     ]
 )
+
+if Context.environment["SWIFT_SYNTAX_EXTENSION_MACRO_FIXED"] != nil {
+    package.dependencies.remove(at: 0)
+    package.dependencies.append(
+        .package(
+            url: "https://github.com/soumyamahunt/swift-syntax.git",
+            branch: "extension-macro-assert-fix"
+        )
+    )
+
+    package.targets.forEach { target in
+        var settings = target.swiftSettings ?? []
+        settings.append(.define("SWIFT_SYNTAX_EXTENSION_MACRO_FIXED"))
+        target.swiftSettings = settings
+    }
+}
diff --git a/Tests/MetaCodableTests/CodableTests.swift b/Tests/MetaCodableTests/CodableTests.swift
index 3dce6e70a..0c158df30 100644
--- a/Tests/MetaCodableTests/CodableTests.swift
+++ b/Tests/MetaCodableTests/CodableTests.swift
@@ -104,7 +104,8 @@ final class CodableTests: XCTestCase {
                         case value = "value"
                     }
                 }
-                """
+                """,
+            conformsTo: ["Codable": ["Decodable"]]
         )
     }
 
@@ -142,7 +143,8 @@ final class CodableTests: XCTestCase {
                         case value = "value"
                     }
                 }
-                """
+                """,
+            conformsTo: ["Codable": ["Encodable"]]
         )
     }
 
@@ -173,7 +175,8 @@ final class CodableTests: XCTestCase {
                     func encode(to encoder: Encoder) throws {
                     }
                 }
-                """
+                """,
+            conformsTo: ["Codable": []]
         )
     }
 }
@@ -182,6 +185,9 @@ func assertMacroExpansion(
     _ originalSource: String,
     expandedSource: String,
     diagnostics: [DiagnosticSpec] = [],
+    conformsTo conformanceMap: [String: [TypeSyntax]] = [
+        "Codable": ["Decodable", "Encodable"]
+    ],
     testModuleName: String = "TestModule",
     testFileName: String = "test.swift",
     indentationWidth: Trivia = .spaces(4),
@@ -204,6 +210,7 @@ func assertMacroExpansion(
             "CodingKeys": CodingKeys.self,
             "IgnoreCodingInitialized": IgnoreCodingInitialized.self,
         ],
+        conformsTo: conformanceMap,
         testModuleName: testModuleName, testFileName: testFileName,
         indentationWidth: indentationWidth,
         file: file, line: line
@@ -221,14 +228,9 @@ extension DiagnosticSpec {
         return .init(
             id: MessageID(
                 domain: "SwiftSyntaxMacroExpansion",
-                id: "accessorMacroOnVariableWithMultipleBindings"
+                id: "peerMacroOnVariableWithMultipleBindings"
             ),
-            message:
-                "swift-syntax applies macros syntactically and"
-                + " there is no way to represent a variable declaration"
-                + " with multiple bindings that have accessors syntactically."
-                + " While the compiler allows this expansion,"
-                + " swift-syntax cannot represent it and thus disallows it.",
+            message: "peer macro can only be applied to a single variable",
             line: line, column: column
         )
     }
diff --git a/Tests/MetaCodableTests/CodedAtTests.swift b/Tests/MetaCodableTests/CodedAtTests.swift
index 9c6941d74..8ab037bd7 100644
--- a/Tests/MetaCodableTests/CodedAtTests.swift
+++ b/Tests/MetaCodableTests/CodedAtTests.swift
@@ -51,16 +51,7 @@ final class CodedAtTests: XCTestCase {
                 }
                 """,
             diagnostics: [
-                .multiBinding(line: 2, column: 5),
-                .init(
-                    id: CodedAt.misuseID,
-                    message:
-                        "@CodedAt can't be used with grouped variables declaration",
-                    line: 2, column: 5,
-                    fixIts: [
-                        .init(message: "Remove @CodedAt attribute")
-                    ]
-                ),
+                .multiBinding(line: 2, column: 5)
             ]
         )
     }
diff --git a/Tests/MetaCodableTests/GroupedMutableVariableTests.swift b/Tests/MetaCodableTests/GroupedMutableVariableTests.swift
index 4c2d28a10..45a0ec37c 100644
--- a/Tests/MetaCodableTests/GroupedMutableVariableTests.swift
+++ b/Tests/MetaCodableTests/GroupedMutableVariableTests.swift
@@ -50,8 +50,7 @@ final class GroupedMutableVariableTests: XCTestCase {
                         case three = "three"
                     }
                 }
-                """,
-            diagnostics: [.multiBinding(line: 4, column: 5)]
+                """
         )
     }
 
@@ -106,8 +105,7 @@ final class GroupedMutableVariableTests: XCTestCase {
                         case three = "three"
                     }
                 }
-                """,
-            diagnostics: [.multiBinding(line: 4, column: 5)]
+                """
         )
     }
 
@@ -199,8 +197,7 @@ final class GroupedMutableVariableTests: XCTestCase {
                         case three = "three"
                     }
                 }
-                """,
-            diagnostics: [.multiBinding(line: 4, column: 5)]
+                """
         )
     }
 
@@ -255,8 +252,7 @@ final class GroupedMutableVariableTests: XCTestCase {
                         case three = "three"
                     }
                 }
-                """,
-            diagnostics: [.multiBinding(line: 4, column: 5)]
+                """
         )
     }
 
@@ -311,8 +307,7 @@ final class GroupedMutableVariableTests: XCTestCase {
                         case three = "three"
                     }
                 }
-                """,
-            diagnostics: [.multiBinding(line: 4, column: 5)]
+                """
         )
     }
 }
diff --git a/Tests/MetaCodableTests/GroupedVariableTests.swift b/Tests/MetaCodableTests/GroupedVariableTests.swift
index 3baf84eee..83aba681e 100644
--- a/Tests/MetaCodableTests/GroupedVariableTests.swift
+++ b/Tests/MetaCodableTests/GroupedVariableTests.swift
@@ -50,8 +50,7 @@ final class GroupedVariableTests: XCTestCase {
                         case three = "three"
                     }
                 }
-                """,
-            diagnostics: [.multiBinding(line: 4, column: 5)]
+                """
         )
     }
 
@@ -97,8 +96,7 @@ final class GroupedVariableTests: XCTestCase {
                         case two = "two"
                     }
                 }
-                """,
-            diagnostics: [.multiBinding(line: 4, column: 5)]
+                """
         )
     }
 
@@ -186,8 +184,7 @@ final class GroupedVariableTests: XCTestCase {
                         case three = "three"
                     }
                 }
-                """,
-            diagnostics: [.multiBinding(line: 4, column: 5)]
+                """
         )
     }
 
@@ -233,8 +230,7 @@ final class GroupedVariableTests: XCTestCase {
                         case three = "three"
                     }
                 }
-                """,
-            diagnostics: [.multiBinding(line: 4, column: 5)]
+                """
         )
     }
 
@@ -280,8 +276,7 @@ final class GroupedVariableTests: XCTestCase {
                         case three = "three"
                     }
                 }
-                """,
-            diagnostics: [.multiBinding(line: 4, column: 5)]
+                """
         )
     }
 }
diff --git a/package.json b/package.json
index 6abb89e1d..97147086e 100644
--- a/package.json
+++ b/package.json
@@ -20,7 +20,7 @@
   },
   "scripts": {
     "build": "npm exec --package=swiftylab-ci -- build.js",
-    "test": "npm exec --package=swiftylab-ci -- test.js",
+    "test": "SWIFT_SYNTAX_EXTENSION_MACRO_FIXED=true npm exec --package=swiftylab-ci -- test.js",
     "archive": "echo implement",
     "generate": "echo implement",
     "format": "npm exec --package=swiftylab-ci -- format.js",