diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 000000000..5ace4600a
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,6 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
diff --git a/.github/workflows/automerge.yml b/.github/workflows/automerge.yml
index b9ac3ab08..d3f5e7ddd 100644
--- a/.github/workflows/automerge.yml
+++ b/.github/workflows/automerge.yml
@@ -18,7 +18,7 @@ on:
 jobs:
   create_merge_pr:
     name: Create PR to merge main into release branch
-    uses: swiftlang/github-workflows/.github/workflows/create_automerge_pr.yml@main
+    uses: swiftlang/github-workflows/.github/workflows/create_automerge_pr.yml@0.0.3
     with:
       head_branch: main
       base_branch: release/6.3
diff --git a/.github/workflows/main_using_main.yml b/.github/workflows/main_using_main.yml
index dbf27c0f4..2b7c9ac16 100644
--- a/.github/workflows/main_using_main.yml
+++ b/.github/workflows/main_using_main.yml
@@ -15,7 +15,7 @@ concurrency:
 jobs:
   tests:
     name: Test
-    uses: swiftlang/github-workflows/.github/workflows/swift_package_test.yml@main
+    uses: swiftlang/github-workflows/.github/workflows/swift_package_test.yml@0.0.2
     with:
       linux_swift_versions: '["nightly-main"]'
       linux_os_versions: '["amazonlinux2", "jammy"]'
diff --git a/.github/workflows/main_using_release.yml b/.github/workflows/main_using_release.yml
index b861be1f8..ef6742d82 100644
--- a/.github/workflows/main_using_release.yml
+++ b/.github/workflows/main_using_release.yml
@@ -15,7 +15,7 @@ concurrency:
 jobs:
   tests:
     name: Test
-    uses: swiftlang/github-workflows/.github/workflows/swift_package_test.yml@main
+    uses: swiftlang/github-workflows/.github/workflows/swift_package_test.yml@0.0.2
     with:
       linux_swift_versions: '["nightly-6.2"]'
       linux_os_versions: '["amazonlinux2", "jammy"]'
diff --git a/.github/workflows/pull_request.yml b/.github/workflows/pull_request.yml
index 086b2226e..ca6aa7446 100644
--- a/.github/workflows/pull_request.yml
+++ b/.github/workflows/pull_request.yml
@@ -14,11 +14,11 @@ concurrency:
 jobs:
   tests:
     name: Test
-    uses: swiftlang/github-workflows/.github/workflows/swift_package_test.yml@main
+    uses: swiftlang/github-workflows/.github/workflows/swift_package_test.yml@0.0.2
     with:
-      linux_swift_versions: '["nightly-main", "nightly-6.2"]'
+      linux_swift_versions: '["nightly-main", "nightly-6.3", "nightly-6.2"]'
       linux_os_versions: '["amazonlinux2", "jammy"]'
-      windows_swift_versions: '["nightly-main", "nightly-6.2"]'
+      windows_swift_versions: '["nightly-main", "nightly-6.3", "nightly-6.2"]'
       enable_macos_checks: true
       macos_exclude_xcode_versions: '[{"xcode_version": "16.2"}, {"xcode_version": "16.3"}, {"xcode_version": "16.4"}]'
       enable_ios_checks: true
@@ -27,7 +27,7 @@ jobs:
       enable_android_sdk_build: true
   soundness:
     name: Soundness
-    uses: swiftlang/github-workflows/.github/workflows/soundness.yml@main
+    uses: swiftlang/github-workflows/.github/workflows/soundness.yml@0.0.3
     with:
       license_header_check_project_name: "Swift"
       docs_check_enabled: false
diff --git a/Sources/Testing/ABI/ABI.Record.swift b/Sources/Testing/ABI/ABI.Record.swift
index 40a8d4bc3..2c101ec40 100644
--- a/Sources/Testing/ABI/ABI.Record.swift
+++ b/Sources/Testing/ABI/ABI.Record.swift
@@ -70,8 +70,17 @@ extension ABI.Record: Codable {
   init(from decoder: any Decoder) throws {
     let container = try decoder.container(keyedBy: CodingKeys.self)
 
-    let versionNumber = try container.decode(VersionNumber.self, forKey: .version)
-    if versionNumber != V.versionNumber {
+    func validateVersionNumber(_ versionNumber: VersionNumber) throws {
+      if versionNumber == V.versionNumber {
+        return
+      }
+#if !hasFeature(Embedded)
+      // Allow for alternate version numbers if they correspond to the expected
+      // record version (e.g. "1.2.3" might map to `v1_2_0` without a problem.)
+      if ABI.version(forVersionNumber: versionNumber) == V.self {
+        return
+      }
+#endif
       throw DecodingError.dataCorrupted(
         DecodingError.Context(
           codingPath: decoder.codingPath + CollectionOfOne(CodingKeys.version as any CodingKey),
@@ -79,6 +88,8 @@ extension ABI.Record: Codable {
         )
       )
     }
+    let versionNumber = try container.decode(VersionNumber.self, forKey: .version)
+    try validateVersionNumber(versionNumber)
 
     switch try container.decode(String.self, forKey: .kind) {
     case "test":
diff --git a/Sources/Testing/ABI/ABI.swift b/Sources/Testing/ABI/ABI.swift
index 7a33970fc..9590949a6 100644
--- a/Sources/Testing/ABI/ABI.swift
+++ b/Sources/Testing/ABI/ABI.swift
@@ -43,7 +43,7 @@ extension ABI {
   }
 
   /// The current supported ABI version (ignoring any experimental versions.)
-  typealias CurrentVersion = v0
+  typealias CurrentVersion = v6_3
 
   /// The highest defined and supported ABI version (including any experimental
   /// versions.)
@@ -55,10 +55,18 @@ extension ABI {
   /// - Parameters:
   ///   - versionNumber: The ABI version number for which a concrete type is
   ///     needed.
+  ///   - swiftCompilerVersion: The version number of the Swift compiler. This
+  ///     is used when `versionNumber` is greater than the highest known version
+  ///     to determine whether a version type can be returned. The default value
+  ///     is the version of the Swift compiler which was used to build the
+  ///     testing library.
   ///
   /// - Returns: A type conforming to ``ABI/Version`` that represents the given
   ///   ABI version, or `nil` if no such type exists.
-  static func version(forVersionNumber versionNumber: VersionNumber = ABI.CurrentVersion.versionNumber) -> (any Version.Type)? {
+  static func version(
+    forVersionNumber versionNumber: VersionNumber,
+    givenSwiftCompilerVersion swiftCompilerVersion: @autoclosure () -> VersionNumber = swiftCompilerVersion
+  ) -> (any Version.Type)? {
     if versionNumber > ABI.HighestVersion.versionNumber {
       // If the caller requested an ABI version higher than the current Swift
       // compiler version and it's not an ABI version we've explicitly defined,
@@ -71,7 +79,7 @@ extension ABI {
       // Note also that building an old version of Swift Testing with a newer
       // compiler may produce incorrect results here. We don't generally support
       // that configuration though.
-      if versionNumber > swiftCompilerVersion {
+      if versionNumber > swiftCompilerVersion() {
         return nil
       }
     }
diff --git a/Sources/Testing/Issues/KnownIssue.swift b/Sources/Testing/Issues/KnownIssue.swift
index f59185388..17214c12c 100644
--- a/Sources/Testing/Issues/KnownIssue.swift
+++ b/Sources/Testing/Issues/KnownIssue.swift
@@ -77,6 +77,13 @@ struct KnownIssueScope: Sendable {
 ///   - sourceLocation: The source location to which the issue should be
 ///     attributed.
 private func _matchError(_ error: any Error, in scope: KnownIssueScope, comment: Comment?, sourceLocation: SourceLocation) throws {
+  // ExpectationFailedError is thrown by expectation checking functions to
+  // indicate a condition evaluated to `false`. Those functions record their
+  // own issue, so we don't need to create a new issue and attempt to match it.
+  if error is ExpectationFailedError {
+    return
+  }
+
   let sourceContext = SourceContext(backtrace: Backtrace(forFirstThrowOf: error), sourceLocation: sourceLocation)
   var issue = Issue(kind: .errorCaught(error), comments: [], sourceContext: sourceContext)
   if let context = scope.matcher(issue) {
diff --git a/Sources/Testing/Running/Runner.swift b/Sources/Testing/Running/Runner.swift
index a6a76189e..9a04f6d7e 100644
--- a/Sources/Testing/Running/Runner.swift
+++ b/Sources/Testing/Running/Runner.swift
@@ -77,7 +77,7 @@ extension Runner {
   /// type at runtime, it may be better-suited for ``Configuration`` instead.
   private struct _Context: Sendable {
     /// A serializer used to reduce parallelism among test cases.
-    var testCaseSerializer: Serializer?
+    var testCaseSerializer: Serializer<Void>?
   }
 
   /// Apply the custom scope for any test scope providers of the traits
diff --git a/Sources/Testing/Support/Serializer.swift b/Sources/Testing/Support/Serializer.swift
index 94f7d4f5b..fee310bc7 100644
--- a/Sources/Testing/Support/Serializer.swift
+++ b/Sources/Testing/Support/Serializer.swift
@@ -42,8 +42,13 @@ var defaultParallelizationWidth: Int {
 /// items do not start running; they must wait until the suspended work item
 /// either returns or throws an error.
 ///
+/// The generic type parameter `T` is unused. It avoids warnings when multiple
+/// copies of the testing library are loaded into a runner process on platforms
+/// which use the Objective-C runtime, due to non-generic actor types being
+/// implemented as classes there.
+///
 /// This type is not part of the public interface of the testing library.
-final actor Serializer {
+final actor Serializer<T> {
   /// The maximum number of work items that may run concurrently.
   nonisolated let maximumWidth: Int
 
diff --git a/Tests/TestingTests/KnownIssueTests.swift b/Tests/TestingTests/KnownIssueTests.swift
index 9174bfdd8..88deef5ec 100644
--- a/Tests/TestingTests/KnownIssueTests.swift
+++ b/Tests/TestingTests/KnownIssueTests.swift
@@ -574,6 +574,26 @@ final class KnownIssueTests: XCTestCase {
     await fulfillment(of: [issueRecorded, knownIssueNotRecorded], timeout: 0.0)
   }
 
+  func testKnownIssueWithRequiredExpectationFailure() async {
+    let issueRecorded = expectation(description: "Issue recorded")
+
+    var configuration = Configuration()
+    configuration.eventHandler = { event, _ in
+      guard case .issueRecorded = event.kind else {
+        return
+      }
+      issueRecorded.fulfill()
+    }
+
+    await Test {
+      withKnownIssue {
+        try #require(Bool(false))
+      }
+    }.run(configuration: configuration)
+
+    await fulfillment(of: [issueRecorded], timeout: 0.0)
+  }
+
   func testAsyncKnownIssueThatDoesNotAlwaysOccur() async {
     struct MyError: Error {}
 
diff --git a/Tests/TestingTests/SwiftPMTests.swift b/Tests/TestingTests/SwiftPMTests.swift
index 2d7001e8f..44877a1df 100644
--- a/Tests/TestingTests/SwiftPMTests.swift
+++ b/Tests/TestingTests/SwiftPMTests.swift
@@ -302,10 +302,11 @@ struct SwiftPMTests {
 
   @Test("New-but-not-experimental ABI version")
   func newButNotExperimentalABIVersion() async throws {
-    var versionNumber = ABI.CurrentVersion.versionNumber
-    versionNumber.patchComponent += 1
-    let version = try #require(ABI.version(forVersionNumber: versionNumber))
-    #expect(version.versionNumber == ABI.v0.versionNumber)
+    let currentVersionNumber = ABI.CurrentVersion.versionNumber
+    var newerVersionNumber = currentVersionNumber
+    newerVersionNumber.patchComponent += 1
+    let version = try #require(ABI.version(forVersionNumber: newerVersionNumber, givenSwiftCompilerVersion: newerVersionNumber))
+    #expect(version.versionNumber == currentVersionNumber)
   }
 
   @Test("Unsupported ABI version")