diff --git a/CodeGeneration/Sources/SyntaxSupport/DeclNodes.swift b/CodeGeneration/Sources/SyntaxSupport/DeclNodes.swift
index 4c5a1061d4d..3ae3005bfce 100644
--- a/CodeGeneration/Sources/SyntaxSupport/DeclNodes.swift
+++ b/CodeGeneration/Sources/SyntaxSupport/DeclNodes.swift
@@ -120,6 +120,8 @@ public let DECL_NODES: [Node] = [
           .keyword(._modify),
           .keyword(.modify),
           .keyword(.`init`),
+          .keyword(.borrow),
+          .keyword(.mutate),
         ])
       ),
       Child(
diff --git a/CodeGeneration/Sources/SyntaxSupport/ExperimentalFeatures.swift b/CodeGeneration/Sources/SyntaxSupport/ExperimentalFeatures.swift
index f14f1de8e9d..690792dad47 100644
--- a/CodeGeneration/Sources/SyntaxSupport/ExperimentalFeatures.swift
+++ b/CodeGeneration/Sources/SyntaxSupport/ExperimentalFeatures.swift
@@ -23,6 +23,7 @@ public enum ExperimentalFeature: String, CaseIterable {
   case oldOwnershipOperatorSpellings
   case defaultIsolationPerFile
   case moduleSelector
+  case borrowAndMutateAccessors
 
   /// The name of the feature as it is written in the compiler's `Features.def` file.
   public var featureName: String {
@@ -47,6 +48,8 @@ public enum ExperimentalFeature: String, CaseIterable {
       return "DefaultIsolationPerFile"
     case .moduleSelector:
       return "ModuleSelector"
+    case .borrowAndMutateAccessors:
+      return "BorrowAndMutateAccessors"
     }
   }
 
@@ -73,6 +76,8 @@ public enum ExperimentalFeature: String, CaseIterable {
       return "set default actor isolation for a file"
     case .moduleSelector:
       return "Module selector syntax (`ModName::identifier`)"
+    case .borrowAndMutateAccessors:
+      return "borrow and mutate accessors"
     }
   }
 
diff --git a/CodeGeneration/Sources/SyntaxSupport/KeywordSpec.swift b/CodeGeneration/Sources/SyntaxSupport/KeywordSpec.swift
index e4a66399721..2b1809ae634 100644
--- a/CodeGeneration/Sources/SyntaxSupport/KeywordSpec.swift
+++ b/CodeGeneration/Sources/SyntaxSupport/KeywordSpec.swift
@@ -201,6 +201,7 @@ public enum Keyword: CaseIterable {
   case metadata
   case modify
   case module
+  case mutate
   case mutableAddressWithNativeOwner
   case mutableAddressWithOwner
   case mutating
@@ -535,6 +536,8 @@ public enum Keyword: CaseIterable {
       return KeywordSpec("modify", experimentalFeature: .coroutineAccessors)
     case .module:
       return KeywordSpec("module")
+    case .mutate:
+      return KeywordSpec("mutate", experimentalFeature: .borrowAndMutateAccessors)
     case .mutableAddressWithNativeOwner:
       return KeywordSpec("mutableAddressWithNativeOwner")
     case .mutableAddressWithOwner:
diff --git a/Sources/SwiftParser/TokenPrecedence.swift b/Sources/SwiftParser/TokenPrecedence.swift
index c0edb214bff..55dd9ffb769 100644
--- a/Sources/SwiftParser/TokenPrecedence.swift
+++ b/Sources/SwiftParser/TokenPrecedence.swift
@@ -239,7 +239,7 @@ enum TokenPrecedence: Comparable {
       .dependsOn, .scoped, .sending,
       // Accessors
       .get, .set, .didSet, .willSet, .unsafeAddress, .addressWithOwner, .addressWithNativeOwner, .unsafeMutableAddress,
-      .mutableAddressWithOwner, .mutableAddressWithNativeOwner, ._read, .read, ._modify, .modify,
+      .mutableAddressWithOwner, .mutableAddressWithNativeOwner, ._read, .read, ._modify, .modify, .mutate,
       // Misc
       .import, .using:
       self = .declKeyword
diff --git a/Sources/SwiftParser/generated/ExperimentalFeatures.swift b/Sources/SwiftParser/generated/ExperimentalFeatures.swift
index 1c12c14a148..b04cdfcd946 100644
--- a/Sources/SwiftParser/generated/ExperimentalFeatures.swift
+++ b/Sources/SwiftParser/generated/ExperimentalFeatures.swift
@@ -55,6 +55,9 @@ extension Parser.ExperimentalFeatures {
   /// Whether to enable the parsing of Module selector syntax (`ModName::identifier`).
   public static let moduleSelector = Self (rawValue: 1 << 9)
 
+  /// Whether to enable the parsing of borrow and mutate accessors.
+  public static let borrowAndMutateAccessors = Self (rawValue: 1 << 10)
+
   /// Creates a new value representing the experimental feature with the
   /// given name, or returns nil if the name is not recognized.
   public init?(name: String) {
@@ -79,6 +82,8 @@ extension Parser.ExperimentalFeatures {
       self = .defaultIsolationPerFile
     case "ModuleSelector":
       self = .moduleSelector
+    case "BorrowAndMutateAccessors":
+      self = .borrowAndMutateAccessors
     default:
       return nil
     }
diff --git a/Sources/SwiftParser/generated/Parser+TokenSpecSet.swift b/Sources/SwiftParser/generated/Parser+TokenSpecSet.swift
index ecc4bea5e93..92d9b8d96a4 100644
--- a/Sources/SwiftParser/generated/Parser+TokenSpecSet.swift
+++ b/Sources/SwiftParser/generated/Parser+TokenSpecSet.swift
@@ -39,6 +39,9 @@ extension AccessorDeclSyntax {
     @_spi(ExperimentalLanguageFeatures)
     case modify
     case `init`
+    case borrow
+    @_spi(ExperimentalLanguageFeatures)
+    case mutate
 
     init?(lexeme: Lexer.Lexeme, experimentalFeatures: Parser.ExperimentalFeatures) {
       switch PrepareForKeywordMatch(lexeme) {
@@ -72,6 +75,10 @@ extension AccessorDeclSyntax {
         self = .modify
       case TokenSpec(.`init`):
         self = .`init`
+      case TokenSpec(.borrow):
+        self = .borrow
+      case TokenSpec(.mutate) where experimentalFeatures.contains(.borrowAndMutateAccessors):
+        self = .mutate
       default:
         return nil
       }
@@ -109,6 +116,10 @@ extension AccessorDeclSyntax {
         self = .modify
       case TokenSpec(.`init`):
         self = .`init`
+      case TokenSpec(.borrow):
+        self = .borrow
+      case TokenSpec(.mutate):
+        self = .mutate
       default:
         return nil
       }
@@ -146,6 +157,10 @@ extension AccessorDeclSyntax {
         return .keyword(.modify)
       case .`init`:
         return .keyword(.`init`)
+      case .borrow:
+        return .keyword(.borrow)
+      case .mutate:
+        return .keyword(.mutate)
       }
     }
 
@@ -185,6 +200,10 @@ extension AccessorDeclSyntax {
         return .keyword(.modify)
       case .`init`:
         return .keyword(.`init`)
+      case .borrow:
+        return .keyword(.borrow)
+      case .mutate:
+        return .keyword(.mutate)
       }
     }
   }
diff --git a/Sources/SwiftSyntax/generated/Keyword.swift b/Sources/SwiftSyntax/generated/Keyword.swift
index 61e59e93cbc..f557d35d503 100644
--- a/Sources/SwiftSyntax/generated/Keyword.swift
+++ b/Sources/SwiftSyntax/generated/Keyword.swift
@@ -145,6 +145,8 @@ public enum Keyword: UInt8, Hashable, Sendable {
   @_spi(ExperimentalLanguageFeatures)
   case modify
   case module
+  @_spi(ExperimentalLanguageFeatures)
+  case mutate
   case mutableAddressWithNativeOwner
   case mutableAddressWithOwner
   case mutating
@@ -403,6 +405,8 @@ public enum Keyword: UInt8, Hashable, Sendable {
         self = .modify
       case "module":
         self = .module
+      case "mutate":
+        self = .mutate
       case "prefix":
         self = .prefix
       case "public":
@@ -883,6 +887,7 @@ public enum Keyword: UInt8, Hashable, Sendable {
     "metadata",
     "modify",
     "module",
+    "mutate",
     "mutableAddressWithNativeOwner",
     "mutableAddressWithOwner",
     "mutating",
diff --git a/Sources/SwiftSyntax/generated/raw/RawSyntaxValidation.swift b/Sources/SwiftSyntax/generated/raw/RawSyntaxValidation.swift
index a768f46192f..437ec0f5d05 100644
--- a/Sources/SwiftSyntax/generated/raw/RawSyntaxValidation.swift
+++ b/Sources/SwiftSyntax/generated/raw/RawSyntaxValidation.swift
@@ -264,7 +264,9 @@ func validateLayout(layout: RawSyntaxBuffer, as kind: SyntaxKind) {
       .keyword("read"),
       .keyword("_modify"),
       .keyword("modify"),
-      .keyword("init")
+      .keyword("init"),
+      .keyword("borrow"),
+      .keyword("mutate")
     ]))
     assertNoError(kind, 6, verify(layout[6], as: RawUnexpectedNodesSyntax?.self))
     assertNoError(kind, 7, verify(layout[7], as: RawAccessorParametersSyntax?.self))
diff --git a/Sources/SwiftSyntax/generated/syntaxNodes/SyntaxNodesAB.swift b/Sources/SwiftSyntax/generated/syntaxNodes/SyntaxNodesAB.swift
index 4e07265bc4a..d59177a6260 100644
--- a/Sources/SwiftSyntax/generated/syntaxNodes/SyntaxNodesAB.swift
+++ b/Sources/SwiftSyntax/generated/syntaxNodes/SyntaxNodesAB.swift
@@ -825,7 +825,7 @@ public struct AccessorBlockSyntax: SyntaxProtocol, SyntaxHashable, _LeafSyntaxNo
 /// 
 ///  - `attributes`: ``AttributeListSyntax``
 ///  - `modifier`: ``DeclModifierSyntax``?
-///  - `accessorSpecifier`: (`get` | `set` | `didSet` | `willSet` | `unsafeAddress` | `addressWithOwner` | `addressWithNativeOwner` | `unsafeMutableAddress` | `mutableAddressWithOwner` | `mutableAddressWithNativeOwner` | `_read` | `read` | `_modify` | `modify` | `init`)
+///  - `accessorSpecifier`: (`get` | `set` | `didSet` | `willSet` | `unsafeAddress` | `addressWithOwner` | `addressWithNativeOwner` | `unsafeMutableAddress` | `mutableAddressWithOwner` | `mutableAddressWithNativeOwner` | `_read` | `read` | `_modify` | `modify` | `init` | `borrow` | `mutate`)
 ///  - `parameters`: ``AccessorParametersSyntax``?
 ///  - `effectSpecifiers`: ``AccessorEffectSpecifiersSyntax``?
 ///  - `body`: ``CodeBlockSyntax``?
@@ -1001,6 +1001,8 @@ public struct AccessorDeclSyntax: DeclSyntaxProtocol, SyntaxHashable, _LeafDeclS
   ///  - `_modify`
   ///  - `modify`
   ///  - `init`
+  ///  - `borrow`
+  ///  - `mutate`
   public var accessorSpecifier: TokenSyntax {
     get {
       return Syntax(self).child(at: 5)!.cast(TokenSyntax.self)
diff --git a/Tests/SwiftParserTest/DeclarationTests.swift b/Tests/SwiftParserTest/DeclarationTests.swift
index d72f00824b1..dfce19135e3 100644
--- a/Tests/SwiftParserTest/DeclarationTests.swift
+++ b/Tests/SwiftParserTest/DeclarationTests.swift
@@ -3473,6 +3473,28 @@ final class DeclarationTests: ParserTestCase {
     )
   }
 
+  func testBorrowAndMutateAccessors() {
+    assertParse(
+      """
+      public class Klass {}
+
+      public struct Wrapper {
+        var _otherK: Klass
+
+        var k1: Klass {
+          borrow {
+            return _otherK
+          }
+          mutate {
+            return &_otherK
+          }
+        }
+      }
+      """,
+      experimentalFeatures: .borrowAndMutateAccessors
+    )
+  }
+
   func testMissingCommaInParameters() {
     assertParse(
       "func a(foo: Bar1️⃣ foo2: Bar2) {}",