mattpolzin · mattpolzin · Jan 27, 2026 · Feb 4, 2026 · Feb 10, 2026 · Feb 10, 2026
diff --git a/.github/workflows/codecov.yml b/.github/workflows/codecov.yml
@@ -5,7 +5,7 @@ on: [pull_request]
 jobs:
   codecov:
     container: 
-      image: swift:5.10
+      image: swift:6.2
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v5

diff --git a/.github/workflows/documentation.yml b/.github/workflows/documentation.yml
@@ -9,7 +9,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     container: 
-      image: swift:5.10
+      image: swift:6.2
 
     steps:
       - uses: actions/checkout@v5

diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
@@ -13,8 +13,6 @@ jobs:
       fail-fast: false
       matrix:
         image:
-          - swift:5.10-focal
-          - swift:5.10-jammy
           - swift:6.0-focal
           - swift:6.0-jammy
           - swift:6.0-noble

diff --git a/Package.resolved b/Package.resolved
diff --git a/Package.swift b/Package.swift
@@ -1,4 +1,4 @@
-// swift-tools-version: 5.10
+// swift-tools-version: 6.0
 
 import PackageDescription
 
@@ -21,7 +21,7 @@ let package = Package(
     ],
     dependencies: [
         .package(url: "https://github.com/apple/swift-docc-plugin", from: "1.0.0"),
-        .package(url: "https://github.com/jpsim/Yams.git", "5.1.0"..<"7.0.0") // just for tests
+        .package(url: "https://github.com/jpsim/Yams.git", "6.0.0"..<"7.0.0") // just for tests
     ],
     targets: [
         .target(
@@ -74,5 +74,5 @@ let package = Package(
             name: "OpenAPIKitCompatTests",
             dependencies: ["OpenAPIKitCompat"])
     ],
-    swiftLanguageVersions: [ .v5 ]
+    swiftLanguageModes: [ .v5, .v6 ]
 )
diff --git a/README.md b/README.md
@@ -1,4 +1,4 @@
-[![sswg:sandbox|94x20](https://img.shields.io/badge/sswg-sandbox-lightgrey.svg)](https://github.com/swift-server/sswg/blob/master/process/incubation.md#sandbox-level) [![Swift 5.10+](http://img.shields.io/badge/Swift-5.10+-blue.svg)](https://swift.org)
+[![sswg:sandbox|94x20](https://img.shields.io/badge/sswg-sandbox-lightgrey.svg)](https://github.com/swift-server/sswg/blob/master/process/incubation.md#sandbox-level) [![Swift 6.0+](http://img.shields.io/badge/Swift-6.0+-blue.svg)](https://swift.org)
 
 [![MIT license](http://img.shields.io/badge/license-MIT-lightgrey.svg)](http://opensource.org/licenses/MIT) ![Tests](https://github.com/mattpolzin/OpenAPIKit/actions/workflows/tests.yml/badge.svg?branch=main)
 
@@ -16,9 +16,9 @@ versions and key features are supported by which OpenAPIKit versions.
 
 | OpenAPIKit | Swift | OpenAPI v3.0, v3.1 | External Dereferencing & Sendable | OpenAPI v3.2 |
 |------------|-------|--------------------|-----------------------------------|--------------|
-| v3.x       | 5.1+  | ✅                 |                                   |              |
 | v4.x       | 5.8+  | ✅                 | ✅                                |              |
 | v5.x       | 5.10+ | ✅                 | ✅                                | ✅           |
+| v6.x       | 6.0+  | ✅                 | ✅                                | ✅           |
 
 - [Usage](#usage)
   - [Migration](#migration)

diff --git a/Sources/OpenAPIKitCore/AnyCodable/AnyCodable.swift b/Sources/OpenAPIKitCore/AnyCodable/AnyCodable.swift
@@ -154,10 +154,8 @@ extension AnyCodable: Encodable {
             try container.encode(nsnumber.floatValue)
         case .doubleType, .float64Type, .cgFloatType:
             try container.encode(nsnumber.doubleValue)
-            #if swift(>=5.0)
         @unknown default:
             fatalError()
-            #endif
         }
     }
     #endif

diff --git a/Tests/AnyCodableTests/TestHelpers.swift b/Tests/AnyCodableTests/TestHelpers.swift
@@ -26,7 +26,7 @@ func testStringFromEncoding<T: Encodable>(of entity: T) throws -> String? {
     return String(data: try testEncoder.encode(entity), encoding: .utf8)
 }
 
-func assertJSONEquivalent(_ str1: String?, _ str2: String?, file: StaticString = #file, line: UInt = #line) {
+func assertJSONEquivalent(_ str1: String?, _ str2: String?, file: StaticString = #filePath, line: UInt = #line) {
 
     // when testing on Linux, pretty printing has slightly different
     // meaning so the tests pass on OS X as written but need whitespace

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/ComponentErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/ComponentErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class ComponentErrorTests: XCTestCase {
 

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/DocumentErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/DocumentErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class DocumentErrorTests: XCTestCase {
 

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/Helpers.swift b/Tests/OpenAPIKit30ErrorReportingTests/Helpers.swift
@@ -6,6 +6,6 @@
 //
 
 import Foundation
-@preconcurrency import Yams
+import Yams
 
 var testDecoder: YAMLDecoder { YAMLDecoder() }
diff --git a/Tests/OpenAPIKit30ErrorReportingTests/JSONReferenceErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/JSONReferenceErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class JSONReferenceErrorTests: XCTestCase {
     func test_referenceFailedToParse() {

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/OperationErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/OperationErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class OperationErrorTests: XCTestCase {
     func test_missingResponses() {

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/PathsErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/PathsErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class PathsErrorTests: XCTestCase {
     func test_missingPaths() {

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/RequestContentMapErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/RequestContentMapErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class RequestContentMapErrorTests: XCTestCase {
     /**

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/RequestContentSchemaErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/RequestContentSchemaErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class RequestContentSchemaErrorTests: XCTestCase {
     func test_wrongTypeContentSchemaTypeProperty() {

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/RequestErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/RequestErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class RequestErrorTests: XCTestCase {
     func test_wrongTypeRequest() {

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/ResponseErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/ResponseErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class ResponseErrorTests: XCTestCase {
     func test_headerWithContentAndSchema() {

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/SchemaErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/SchemaErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class SchemaErrorTests: XCTestCase {
     func test_nonIntegerMaximumForIntegerSchema() {

diff --git a/Tests/OpenAPIKit30ErrorReportingTests/SecuritySchemeErrorTests.swift b/Tests/OpenAPIKit30ErrorReportingTests/SecuritySchemeErrorTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class SecuritySchemeErrorTests: XCTestCase {
     func test_missingSecuritySchemeError() {

diff --git a/Tests/OpenAPIKit30RealSpecSuite/GitHubAPITests.swift b/Tests/OpenAPIKit30RealSpecSuite/GitHubAPITests.swift
@@ -7,7 +7,7 @@
 
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 import Foundation
 #if canImport(FoundationNetworking)
 import FoundationNetworking
@@ -27,19 +27,23 @@ final class GitHubAPICampatibilityTests: XCTestCase {
                 commit for now.
          */
         if githubAPI == nil {
+            // Test file can be redownloaded from
+            // https://raw.githubusercontent.com/github/rest-api-description/e4f28959fbc6c9fc4eea823b495061dded87e84d/descriptions/ghes-3.0/ghes-3.0.yaml
             githubAPI = Result {
-                try YAMLDecoder().decode(
-                    OpenAPI.Document.self,
-                    from: String(contentsOf: URL(string: "https://raw.githubusercontent.com/github/rest-api-description/e4f28959fbc6c9fc4eea823b495061dded87e84d/descriptions/ghes-3.0/ghes-3.0.yaml")!)
+                let currentWorkingDirectory = FileManager.default.currentDirectoryPath
+                return try YAMLDecoder().decode(
+                  OpenAPI.Document.self,
+                  from: String(
+                    contentsOf: URL(
+                      filePath: "./Tests/inputs/ghes-3.0.yaml",
+                      relativeTo: URL(filePath: currentWorkingDirectory, directoryHint: .isDirectory)),
+                    encoding: .utf8)
                 )
             }
         }
     }
 
     func test_successfullyParsedDocument() throws {
-        #if os(Linux) && compiler(>=6.0)
-            throw XCTSkip("Swift bug causes CI failure currently (line 48): failed - The operation could not be completed. The file doesn’t exist.")
-        #endif
         switch githubAPI {
         case nil:
             XCTFail("Did not attempt to pull GitHub API documentation like expected.")

diff --git a/Tests/OpenAPIKit30RealSpecSuite/GoogleBooksAPITests.swift b/Tests/OpenAPIKit30RealSpecSuite/GoogleBooksAPITests.swift
@@ -7,7 +7,7 @@
 
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 import Foundation
 #if canImport(FoundationNetworking)
 import FoundationNetworking
@@ -22,19 +22,23 @@ final class GoogleBooksAPICampatibilityTests: XCTestCase {
 
     override func setUp() {
         if booksAPI == nil {
+            // Test file can be redownloaded from
+            // https://raw.githubusercontent.com/APIs-guru/openapi-directory/master/APIs/googleapis.com/books/v1/openapi.yaml
             booksAPI = Result {
-                try YAMLDecoder().decode(
-                    OpenAPI.Document.self,
-                    from: String(contentsOf: URL(string: "https://raw.githubusercontent.com/APIs-guru/openapi-directory/master/APIs/googleapis.com/books/v1/openapi.yaml")!)
+                let currentWorkingDirectory = FileManager.default.currentDirectoryPath
+                return try YAMLDecoder().decode(
+                  OpenAPI.Document.self,
+                  from: String(
+                    contentsOf: URL(
+                      filePath: "./Tests/inputs/google-books-3.0.yaml",
+                      relativeTo: URL(filePath: currentWorkingDirectory, directoryHint: .isDirectory)),
+                    encoding: .utf8)
                 )
             }
         }
     }
 
     func test_successfullyParsedDocument() throws {
-        #if os(Linux) && compiler(>=6.0)
-            throw XCTSkip("Swift bug causes CI failure currently (line 48): failed - The operation could not be completed. The file doesn’t exist.")
-        #endif
         switch booksAPI {
         case nil:
             XCTFail("Did not attempt to pull Google Books API documentation like expected.")

diff --git a/Tests/OpenAPIKit30RealSpecSuite/PetStoreAPITests.swift b/Tests/OpenAPIKit30RealSpecSuite/PetStoreAPITests.swift
@@ -7,7 +7,7 @@
 
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 import Foundation
 #if canImport(FoundationNetworking)
 import FoundationNetworking
@@ -22,19 +22,23 @@ final class PetStoreAPICampatibilityTests: XCTestCase {
 
     override func setUp() {
         if petStoreAPI == nil {
+            // Test file can be redownloaded from
+            // https://raw.githubusercontent.com/swagger-api/swagger-petstore/master/src/main/resources/openapi.yaml
             petStoreAPI = Result {
-                try YAMLDecoder().decode(
-                    OpenAPI.Document.self,
-                    from: String(contentsOf: URL(string: "https://raw.githubusercontent.com/swagger-api/swagger-petstore/master/src/main/resources/openapi.yaml")!)
+                let currentWorkingDirectory = FileManager.default.currentDirectoryPath
+                return try YAMLDecoder().decode(
+                  OpenAPI.Document.self,
+                  from: String(
+                    contentsOf: URL(
+                      filePath: "./Tests/inputs/pet-store-3.0.yaml",
+                      relativeTo: URL(filePath: currentWorkingDirectory, directoryHint: .isDirectory)),
+                    encoding: .utf8)
                 )
             }
         }
     }
 
     func test_successfullyParsedDocument() throws {
-        #if os(Linux) && compiler(>=6.0)
-        throw XCTSkip("Swift bug causes CI failure currently (line 48): failed - The operation could not be completed. The file doesn’t exist.")
-        #endif
         switch petStoreAPI {
         case nil:
             XCTFail("Did not attempt to pull Pet Store API documentation like expected.")

diff --git a/Tests/OpenAPIKit30RealSpecSuite/SwaggerDocSamplesTests.swift b/Tests/OpenAPIKit30RealSpecSuite/SwaggerDocSamplesTests.swift
@@ -8,7 +8,7 @@
 import Foundation
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 
 final class SwaggerDocSamplesTests: XCTestCase {
     func test_allOfExample() throws {

diff --git a/Tests/OpenAPIKit30RealSpecSuite/TomTomAPITests.swift b/Tests/OpenAPIKit30RealSpecSuite/TomTomAPITests.swift
@@ -7,7 +7,7 @@
 
 import XCTest
 import OpenAPIKit30
-@preconcurrency import Yams
+import Yams
 import Foundation
 #if canImport(FoundationNetworking)
 import FoundationNetworking
@@ -22,19 +22,23 @@ final class TomTomAPICampatibilityTests: XCTestCase {
 
     override func setUp() {
         if tomtomAPI == nil {
+            // Test file can be redownloaded from
+            // https://raw.githubusercontent.com/APIs-guru/openapi-directory/c9190db19e5cb151592d44f0d4482839e1e5a8e0/APIs/tomtom.com/search/1.0.0/openapi.yaml
             tomtomAPI = Result {
-                try YAMLDecoder().decode(
-                    OpenAPI.Document.self,
-                    from: String(contentsOf: URL(string: "https://raw.githubusercontent.com/APIs-guru/openapi-directory/c9190db19e5cb151592d44f0d4482839e1e5a8e0/APIs/tomtom.com/search/1.0.0/openapi.yaml")!)
+                let currentWorkingDirectory = FileManager.default.currentDirectoryPath
+                return try YAMLDecoder().decode(
+                  OpenAPI.Document.self,
+                  from: String(
+                    contentsOf: URL(
+                      filePath: "./Tests/inputs/tomtom-3.0.yaml",
+                      relativeTo: URL(filePath: currentWorkingDirectory, directoryHint: .isDirectory)),
+                    encoding: .utf8)
                 )
             }
         }
     }
 
     func test_successfullyParsedDocument() throws {
-        #if os(Linux) && compiler(>=6.0)
-        throw XCTSkip("Swift bug causes CI failure currently (line 43): failed - The operation could not be completed. The file doesn’t exist.")
-        #endif
         switch tomtomAPI {
         case nil:
             XCTFail("Did not attempt to pull TomTom API documentation like expected.")

diff --git a/Tests/OpenAPIKit30Tests/Document/ExternalDereferencingDocumentTests.swift b/Tests/OpenAPIKit30Tests/Document/ExternalDereferencingDocumentTests.swift
@@ -3,7 +3,7 @@
 //  
 
 import Foundation
-@preconcurrency import Yams
+import Yams
 import OpenAPIKit30
 import XCTest