diff --git a/Tests/AuthenticationTests/APIKeyTests.swift b/Tests/AuthenticationTests/APIKeyTests.swift
index 894baa164..58aecba29 100644
--- a/Tests/AuthenticationTests/APIKeyTests.swift
+++ b/Tests/AuthenticationTests/APIKeyTests.swift
@@ -12,33 +12,32 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import XCTest
-
 @testable import Authentication
 
 import JWTKit
+import Testing
 
 
-final class APIKeyTests: XCTestCase {
+@Suite struct APIKeyTests {
 
-    func test_verify() throws {
+    @Test func verify() throws {
         // Ensure verification rejects expired tokens
         let s = Signer(secretSigningKey: "secret")
         let token = try s.generateToken(for: "foo", expiringOn: .distantPast, contact: "bar", tier: .tier1)
         do {
             _ = try s.verifyToken(token)
-            XCTFail("Expected a JWTError.claimVerificationFailure to the thrown")
+            Issue.record("Expected a JWTError.claimVerificationFailure to the thrown")
         } catch let JWTError.claimVerificationFailure(name: name, reason: reason) {
-            XCTAssertEqual(name, "exp")
-            XCTAssertEqual(reason, "expired")
+            #expect(name == "exp")
+            #expect(reason == "expired")
         }
     }
 
-    func test_isAuthorized() throws {
-        XCTAssertTrue(APIKey.mock(tier: .internal).isAuthorized(for: .tier1))
-        XCTAssertTrue(APIKey.mock(tier: .internal).isAuthorized(for: .tier2))
-        XCTAssertTrue(APIKey.mock(tier: .tier1).isAuthorized(for: .tier1))
-        XCTAssertFalse(APIKey.mock(tier: .tier1).isAuthorized(for: .tier2))
+    @Test func isAuthorized() throws {
+        #expect(APIKey.mock(tier: .internal).isAuthorized(for: .tier1))
+        #expect(APIKey.mock(tier: .internal).isAuthorized(for: .tier2))
+        #expect(APIKey.mock(tier: .tier1).isAuthorized(for: .tier1))
+        #expect(!APIKey.mock(tier: .tier1).isAuthorized(for: .tier2))
     }
 
 }
diff --git a/Tests/AuthenticationTests/SignerTests.swift b/Tests/AuthenticationTests/SignerTests.swift
index 65ad25032..15f5a6592 100644
--- a/Tests/AuthenticationTests/SignerTests.swift
+++ b/Tests/AuthenticationTests/SignerTests.swift
@@ -12,33 +12,32 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import XCTest
-
 @testable import Authentication
 
 import JWTKit
+import Testing
 
 
-final class SignerTests: XCTestCase {
+@Suite struct SignerTests {
 
-    func test_generateToken_verifyToken() throws {
+    @Test func generateToken_verifyToken() throws {
         // Round trip test
         let s = Signer(secretSigningKey: "secret")
         let token = try s.generateToken(for: "foo", contact: "bar", tier: .tier1)
-        XCTAssertTrue(!token.isEmpty)
+        #expect(!token.isEmpty)
         let key = try s.verifyToken(token)
-        XCTAssertEqual(key.sub, .init(value: "foo"))
-        XCTAssertEqual(key.contact, "bar")
-        XCTAssertEqual(key.tier, .tier1)
+        #expect(key.sub == .init(value: "foo"))
+        #expect(key.contact == "bar")
+        #expect(key.tier == .tier1)
     }
 
-    func test_verifyToken_failure() throws {
+    @Test func verifyToken_failure() throws {
         // Ensure verification requires the correct secret
         let token = try Signer(secretSigningKey: "secret").generateToken(for: "foo", contact: "bar", tier: .tier1)
         let otherSigner = Signer(secretSigningKey: "other")
         do {
             _ = try otherSigner.verifyToken(token)
-            XCTFail("Expected a JWTError.signatureVerifictionFailed to the thrown")
+            Issue.record("Expected a JWTError.signatureVerifictionFailed to the thrown")
         } catch JWTError.signatureVerifictionFailed { }
     }
 
diff --git a/Tests/AuthenticationTests/TierTests.swift b/Tests/AuthenticationTests/TierTests.swift
index 0a36c8b18..d11bff553 100644
--- a/Tests/AuthenticationTests/TierTests.swift
+++ b/Tests/AuthenticationTests/TierTests.swift
@@ -12,21 +12,21 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import XCTest
-
 @testable import Authentication
 
+import Testing
+
 
-final class TierTests: XCTestCase {
+@Suite struct TierTests {
 
-    func test_Comparable() throws {
-        XCTAssertTrue(Tier<V1>.tier1 < Tier<V1>.tier2)
-        XCTAssertTrue(Tier<V1>.tier2 < Tier<V1>.internal)
+    @Test func Comparable() throws {
+        #expect(Tier<V1>.tier1 < Tier<V1>.tier2)
+        #expect(Tier<V1>.tier2 < Tier<V1>.internal)
 
-        XCTAssertFalse(Tier<V1>.tier1 > Tier<V1>.tier2)
+        #expect(!(Tier<V1>.tier1 > Tier<V1>.tier2))
 
-        XCTAssertTrue(Tier<V1>.tier1 <= Tier<V1>.tier1)
-        XCTAssertTrue(Tier<V1>.tier1 >= Tier<V1>.tier1)
+        #expect(Tier<V1>.tier1 <= Tier<V1>.tier1)
+        #expect(Tier<V1>.tier1 >= Tier<V1>.tier1)
     }
 
 }
diff --git a/Tests/S3StoreTests/S3StoreTests.swift b/Tests/S3StoreTests/S3StoreTests.swift
index 0c8fcacda..4f1a4042b 100644
--- a/Tests/S3StoreTests/S3StoreTests.swift
+++ b/Tests/S3StoreTests/S3StoreTests.swift
@@ -12,36 +12,36 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import XCTest
-
 @testable import S3Store
 
+import Testing
+
 
-final class S3StoreTests: XCTestCase {
+@Suite struct S3StoreTests {
 
-    func test_Key_path() throws {
+    @Test func Key_path() throws {
         do {
             let key = S3Store.Key(bucket: "bucket", path: "foo/bar")
-            XCTAssertEqual(key.path, "foo/bar")
+            #expect(key.path == "foo/bar")
         }
         do {
             let key = S3Store.Key(bucket: "bucket", path: "/foo/bar")
-            XCTAssertEqual(key.path, "foo/bar")
+            #expect(key.path == "foo/bar")
         }
         do {
             let key = S3Store.Key(bucket: "bucket", path: "//foo/bar")
-            XCTAssertEqual(key.path, "foo/bar")
+            #expect(key.path == "foo/bar")
         }
     }
 
-    func test_Key_objectUrl() throws {
+    @Test func Key_objectUrl() throws {
         let key = S3Store.Key(bucket: "bucket", path: "foo/bar")
-        XCTAssertEqual(key.objectUrl, "https://bucket.s3.us-east-2.amazonaws.com/foo/bar")
+        #expect(key.objectUrl == "https://bucket.s3.us-east-2.amazonaws.com/foo/bar")
     }
 
-    func test_Key_s3Uri() throws {
+    @Test func Key_s3Uri() throws {
         let key = S3Store.Key(bucket: "bucket", path: "foo/bar")
-        XCTAssertEqual(key.s3Uri, "s3://bucket/foo/bar")
+        #expect(key.s3Uri == "s3://bucket/foo/bar")
     }
 
 }