Merge pull request #388 from yonaskolb/xcodeproj_5

Upgrade to xcodeproj 6
2026-03-18 20:02:25 +00:00 · 2018-10-14 22:26:15 +11:00
parent 8fcd903679 fd968b0e50
commit 0469c7c679
38 changed files with 3937 additions and 4067 deletions
@@ -2,7 +2,15 @@ version: 2
 jobs:
  macOS_swift_4.1:
    macos:
-      xcode: "9.3.0"
+      xcode: "9.4.0"
+    steps:
+      - checkout
+      - run:
+          name: Build Test Project
+          command: ./build-fixtures.sh
+  macOS_swift_4.2:
+    macos:
+      xcode: "10.0.0"
    steps:
      - checkout
      - run: 
@@ -20,27 +28,6 @@ jobs:
      - run:
          name: Build release
          command: make build
-  macOS_swift_4.2:
-    macos:
-      xcode: "10.0.0"
-    steps:
-      - checkout
-      - run: 
-          name: Build
-          command: swift build
-      - run:
-          name: Test
-          command: swift test 2>&1 | xcpretty
-      # disabled till UUID's are stable
-      # - run:
-      #     name: Check Project Diff
-      #     command: ./diff-fixtures.sh
-      - run:
-          name: Build Test Project
-          command: ./build-fixtures.sh
-      - run:
-          name: Build release
-          command: make build
 workflows:
  version: 2
  workflow:
@@ -5,6 +5,10 @@
 #### Added
 - Added `weak` Weak linking setting for dependencies [411](https://github.com/yonaskolb/XcodeGen/pull/411) @alvarhansen

+#### Changed
+- Performance improvements for large projects [388](https://github.com/yonaskolb/XcodeGen/pull/388) @yonaskolb
+- Upgraded to xcodeproj 6 [388](https://github.com/yonaskolb/XcodeGen/pull/388) @yonaskolb
+- Upgraded to Swift 4.2 [388](https://github.com/yonaskolb/XcodeGen/pull/388) @yonaskolb

 ## 1.11.2

@@ -3,11 +3,11 @@
    "pins": [
      {
        "package": "AEXML",
-        "repositoryURL": "https://github.com/tadija/AEXML.git",
+        "repositoryURL": "https://github.com/tadija/AEXML",
        "state": {
          "branch": null,
-          "revision": "6eea665515d079c338690147082a8084a36484b0",
-          "version": "4.3.0"
+          "revision": "54bb8ea6fb693dd3f92a89e5fcc19e199fdeedd0",
+          "version": "4.3.3"
        }
      },
      {
@@ -24,8 +24,8 @@
        "repositoryURL": "https://github.com/yonaskolb/JSONUtilities.git",
        "state": {
          "branch": null,
-          "revision": "d9f957b1b2a078c93f96c723040d4cbffcb7d3f9",
-          "version": "4.0.2"
+          "revision": "db238f4858ac2ac3fff228b5b71ce90488a6a9b3",
+          "version": "4.1.0"
        }
      },
      {
@@ -46,15 +46,6 @@
          "version": "3.1.4"
        }
      },
-      {
-        "package": "ShellOut",
-        "repositoryURL": "https://github.com/JohnSundell/ShellOut.git",
-        "state": {
-          "branch": null,
-          "revision": "f1c253a34a40df4bfd268b09fdb101b059f6d52d",
-          "version": "2.1.0"
-        }
-      },
      {
        "package": "Spectre",
        "repositoryURL": "https://github.com/kylef/Spectre.git",
@@ -65,12 +56,21 @@
        }
      },
      {
-        "package": "xcproj",
+        "package": "SwiftShell",
+        "repositoryURL": "https://github.com/kareman/SwiftShell",
+        "state": {
+          "branch": null,
+          "revision": "beebe43c986d89ea5359ac3adcb42dac94e5e08a",
+          "version": "4.1.2"
+        }
+      },
+      {
+        "package": "xcodeproj",
        "repositoryURL": "https://github.com/tuist/xcodeproj.git",
        "state": {
          "branch": null,
-          "revision": "5253c22f208558264e3a64a3a29f11537ca1b41a",
-          "version": "4.3.1"
+          "revision": "869ae3f417b0fb545e454ead36e2e13f157265a2",
+          "version": "6.2.0"
        }
      },
      {
@@ -1,4 +1,4 @@
-// swift-tools-version:4.0
+// swift-tools-version:4.2

 import PackageDescription

@@ -13,10 +13,10 @@ let package = Package(
        .package(url: "https://github.com/kylef/PathKit.git", from: "0.9.0"),
        .package(url: "https://github.com/kylef/Commander.git", from: "0.8.0"),
        .package(url: "https://github.com/jpsim/Yams.git", from: "1.0.0"),
-        .package(url: "https://github.com/yonaskolb/JSONUtilities.git", from: "4.0.0"),
+        .package(url: "https://github.com/yonaskolb/JSONUtilities.git", from: "4.1.0"),
        .package(url: "https://github.com/kylef/Spectre.git", from: "0.9.0"),
        .package(url: "https://github.com/onevcat/Rainbow.git", from: "3.0.0"),
-        .package(url: "https://github.com/tuist/xcodeproj.git", from: "4.3.1"),
+        .package(url: "https://github.com/tuist/xcodeproj.git", from: "6.2.0"),
    ],
    targets: [
        .target(name: "XcodeGen", dependencies: [
@@ -27,12 +27,12 @@ let package = Package(
        .target(name: "XcodeGenKit", dependencies: [
          "ProjectSpec",
          "JSONUtilities",
-          "xcproj",
+          "xcodeproj",
          "PathKit",
        ]),
        .target(name: "ProjectSpec", dependencies: [
          "JSONUtilities",
-          "xcproj",
+          "xcodeproj",
          "Yams",
        ]),
        .testTarget(name: "XcodeGenKitTests", dependencies: [
@@ -1,6 +1,5 @@
 import Foundation
 import JSONUtilities
-import xcproj

 public struct Config: Equatable {
    public var name: String
@@ -1,6 +1,5 @@
 import Foundation
 import JSONUtilities
-import xcproj

 public struct Dependency: Equatable {

@@ -1,6 +1,5 @@
 import Foundation
 import JSONUtilities
-import xcproj

 public struct DeploymentTarget: Equatable {

@@ -1,7 +1,6 @@
 import Foundation
 import JSONUtilities
 import PathKit
-import xcproj
 import Yams

 public struct Project: BuildSettingsContainer {
@@ -1,6 +1,6 @@
 import Foundation
 import JSONUtilities
-import xcproj
+import xcodeproj

 public typealias BuildType = XCScheme.BuildAction.Entry.BuildFor

@@ -311,7 +311,7 @@ extension BuildType: JSONPrimitiveConvertible {
    }
 }

-extension XCScheme.EnvironmentVariable: JSONObjectConvertible, Equatable {
+extension XCScheme.EnvironmentVariable: JSONObjectConvertible {

    private static func parseValue(_ value: Any) -> String {
        if let bool = value as? Bool {
@@ -346,10 +346,4 @@ extension XCScheme.EnvironmentVariable: JSONObjectConvertible, Equatable {
            return []
        }
    }
-
-    public static func == (lhs: XCScheme.EnvironmentVariable, rhs: XCScheme.EnvironmentVariable) -> Bool {
-        return lhs.variable == rhs.variable &&
-            lhs.value == rhs.value &&
-            lhs.enabled == rhs.enabled
-    }
 }
@@ -1,7 +1,7 @@
 import Foundation
 import JSONUtilities
 import PathKit
-import xcproj
+import xcodeproj

 public struct Settings: Equatable, JSONObjectConvertible, CustomStringConvertible {

@@ -1,6 +1,5 @@
 import Foundation
 import JSONUtilities
-import xcproj

 public struct SpecOptions: Equatable {

@@ -1,6 +1,6 @@
 import Foundation
 import JSONUtilities
-import xcproj
+import xcodeproj

 public struct LegacyTarget: Equatable {
    public var toolPath: String
@@ -39,14 +39,14 @@ public struct Target: ProjectTarget {
    public var legacy: LegacyTarget?
    public var deploymentTarget: Version?
    public var attributes: [String: Any]
-    internal var productName: String?
+    public var productName: String

    public var isLegacy: Bool {
        return legacy != nil
    }

    public var filename: String {
-        var filename = productName ?? name
+        var filename = productName
        if let fileExtension = type.fileExtension {
            filename += ".\(fileExtension)"
        }
@@ -57,6 +57,7 @@ public struct Target: ProjectTarget {
        name: String,
        type: PBXProductType,
        platform: Platform,
+        productName: String? = nil,
        deploymentTarget: Version? = nil,
        settings: Settings = .empty,
        configFiles: [String: String] = [:],
@@ -76,6 +77,7 @@ public struct Target: ProjectTarget {
        self.type = type
        self.platform = platform
        self.deploymentTarget = deploymentTarget
+        self.productName = productName ?? name
        self.settings = settings
        self.configFiles = configFiles
        self.sources = sources
@@ -230,8 +232,9 @@ extension LegacyTarget: JSONObjectConvertible {
 extension Target: NamedJSONDictionaryConvertible {

    public init(name: String, jsonDictionary: JSONDictionary) throws {
-        self.name = jsonDictionary.json(atKeyPath: "name") ?? name
-        productName = jsonDictionary.json(atKeyPath: "productName")
+        let resolvedName: String = jsonDictionary.json(atKeyPath: "name") ?? name
+        self.name = resolvedName
+        self.productName = jsonDictionary.json(atKeyPath: "productName") ?? resolvedName
        let typeString: String = try jsonDictionary.json(atKeyPath: "type")
        if let type = PBXProductType(string: typeString) {
            self.type = type
@@ -1,6 +1,6 @@
 import Foundation
 import JSONUtilities
-import xcproj
+import xcodeproj

 public struct TargetScheme: Equatable {
    public var testTargets: [String]
@@ -1,7 +1,7 @@
 import Foundation
 import JSONUtilities
 import PathKit
-import xcproj
+import xcodeproj

 public struct TargetSource: Equatable {

@@ -57,7 +57,7 @@ public struct TargetSource: Equatable {
                case sharedSupport
                case plugins

-                public var destination: xcproj.PBXCopyFilesBuildPhase.SubFolder? {
+                public var destination: xcodeproj.PBXCopyFilesBuildPhase.SubFolder? {
                    switch self {
                    case .absolutePath: return .absolutePath
                    case .productsDirectory: return .productsDirectory
@@ -82,7 +82,7 @@ public struct TargetSource: Equatable {
            }
        }

-        public var buildPhase: xcproj.BuildPhase? {
+        public var buildPhase: xcodeproj.BuildPhase? {
            switch self {
            case .sources: return .sources
            case .headers: return .headers
@@ -1,6 +1,6 @@
 import Foundation
 import PathKit
-import xcproj
+import xcodeproj

 extension PBXProductType {

@@ -60,7 +60,7 @@ extension XCScheme.CommandLineArguments {
    public convenience init(_ dict: [String: Bool]) {
        let args = dict.map { tuple in
            XCScheme.CommandLineArguments.CommandLineArgument(name: tuple.key, enabled: tuple.value)
-        }
+        }.sorted { $0.name < $1.name }
        self.init(arguments: args)
    }
 }
@@ -4,7 +4,7 @@ import JSONUtilities
 import PathKit
 import ProjectSpec
 import XcodeGenKit
-import xcproj
+import xcodeproj

 let version = try Version("1.11.2")

@@ -1,8 +1,7 @@
 import Foundation
-import JSONUtilities
 import PathKit
 import ProjectSpec
-import xcproj
+import xcodeproj
 import Yams

 public class PBXProjGenerator {
@@ -12,13 +11,12 @@ public class PBXProjGenerator {
    let pbxProj: PBXProj
    var sourceGenerator: SourceGenerator!

-    var targetObjects: [String: ObjectReference<PBXTarget>] = [:]
-    var targetAggregateObjects: [String: ObjectReference<PBXAggregateTarget>] = [:]
-    var targetBuildFiles: [String: ObjectReference<PBXBuildFile>] = [:]
-    var targetFileReferences: [String: String] = [:]
+    var targetObjects: [String: PBXTarget] = [:]
+    var targetAggregateObjects: [String: PBXAggregateTarget] = [:]
+    var targetFileReferences: [String: PBXFileReference] = [:]

-    var carthageFrameworksByPlatform: [String: Set<String>] = [:]
-    var frameworkFiles: [String] = []
+    var carthageFrameworksByPlatform: [String: Set<PBXFileElement>] = [:]
+    var frameworkFiles: [PBXFileElement] = []

    var generated = false

@@ -28,21 +26,15 @@ public class PBXProjGenerator {

    public init(project: Project) {
        self.project = project
-        pbxProj = PBXProj(rootObject: "", objectVersion: 46)
-        sourceGenerator = SourceGenerator(project: project) { [unowned self] id, object in
-            self.addObject(id: id, object)
+        pbxProj = PBXProj(rootObject: nil, objectVersion: 46)
+        sourceGenerator = SourceGenerator(project: project) { [unowned self] object in
+            _ = self.addObject(object)
        }
    }

-    func addObject(id: String, _ object: PBXObject) -> String {
-        let reference = pbxProj.objects.generateReference(object, id)
-        pbxProj.objects.addObject(object, reference: reference)
-        return reference
-    }
-
-    func createObject<T>(id: String, _ object: T) -> ObjectReference<T> {
-        let reference = addObject(id: id, object)
-        return ObjectReference(reference: reference, object: object)
+    func addObject<T: PBXObject>(_ object: T) -> T {
+        pbxProj.add(object: object)
+        return object
    }

    public func generate() throws -> PBXProj {
@@ -55,35 +47,34 @@ public class PBXProjGenerator {
            try sourceGenerator.getFileGroups(path: group)
        }

-        let buildConfigs: [ObjectReference<XCBuildConfiguration>] = project.configs.map { config in
+        let buildConfigs: [XCBuildConfiguration] = project.configs.map { config in
            let buildSettings = project.getProjectBuildSettings(config: config)
-            var baseConfigurationReference: String?
-            if let configPath = project.configFiles[config.name] {
-                baseConfigurationReference = sourceGenerator.getContainedFileReference(path: project.basePath + configPath)
+            var baseConfiguration: PBXFileReference?
+            if let configPath = project.configFiles[config.name],
+                let fileReference = sourceGenerator.getContainedFileReference(path: project.basePath + configPath) as? PBXFileReference {
+                baseConfiguration = fileReference
            }
-            return createObject(
-                id: config.name,
+            let buildConfig = addObject(
                XCBuildConfiguration(
                    name: config.name,
-                    baseConfigurationReference: baseConfigurationReference,
                    buildSettings: buildSettings
                )
            )
+            buildConfig.baseConfiguration = baseConfiguration
+            return buildConfig
        }

-        let configName = project.options.defaultConfig ?? buildConfigs.first?.object.name ?? ""
-        let buildConfigList = createObject(
-            id: project.name,
+        let configName = project.options.defaultConfig ?? buildConfigs.first?.name ?? ""
+        let buildConfigList = addObject(
            XCConfigurationList(
-                buildConfigurations: buildConfigs.map { $0.reference },
+                buildConfigurations: buildConfigs,
                defaultConfigurationName: configName
            )
        )

-        var derivedGroups: [ObjectReference<PBXGroup>] = []
+        var derivedGroups: [PBXGroup] = []

-        let mainGroup = createObject(
-            id: "Project",
+        let mainGroup = addObject(
            PBXGroup(
                children: [],
                sourceTree: .group,
@@ -93,18 +84,17 @@ public class PBXProjGenerator {
            )
        )

-        let pbxProject = createObject(
-            id: project.name,
+        let pbxProject = addObject(
            PBXProject(
                name: project.name,
-                buildConfigurationList: buildConfigList.reference,
+                buildConfigurationList: buildConfigList,
                compatibilityVersion: "Xcode 3.2",
-                mainGroup: mainGroup.reference,
+                mainGroup: mainGroup,
                developmentRegion: project.options.developmentLanguage ?? "en"
            )
        )

-        pbxProj.rootObject = pbxProject.reference
+        pbxProj.rootObject = pbxProject

        for target in project.targets {
            let targetObject: PBXTarget
@@ -115,26 +105,26 @@ public class PBXProjGenerator {
                    buildToolPath: target.legacy?.toolPath,
                    buildArgumentsString: target.legacy?.arguments,
                    passBuildSettingsInEnvironment: target.legacy?.passSettings ?? false,
-                    buildWorkingDirectory: target.legacy?.workingDirectory
+                    buildWorkingDirectory: target.legacy?.workingDirectory,
+                    buildPhases: []
                )
            } else {
-                targetObject = PBXNativeTarget(name: target.name)
+                targetObject = PBXNativeTarget(name: target.name, buildPhases: [])
            }

-            targetObjects[target.name] = createObject(id: target.name, targetObject)
+            targetObjects[target.name] = addObject(targetObject)

            var explicitFileType: String?
            var lastKnownFileType: String?
-            let fileType = PBXFileReference.fileType(path: Path(target.filename))
+            let fileType = Xcode.fileType(path: Path(target.filename))
            if target.platform == .macOS || target.platform == .watchOS || target.type == .framework {
                explicitFileType = fileType
            } else {
                lastKnownFileType = fileType
            }

-            if !target.isLegacy {
-                let fileReference = createObject(
-                    id: target.name,
+            if !target.isLegacy && targetFileReferences[target.productName] == nil {
+                let fileReference = addObject(
                    PBXFileReference(
                        sourceTree: .buildProductsDir,
                        explicitFileType: explicitFileType,
@@ -144,18 +134,13 @@ public class PBXProjGenerator {
                    )
                )

-                targetFileReferences[target.name] = fileReference.reference
-                targetBuildFiles[target.name] = createObject(
-                    id: fileReference.reference,
-                    PBXBuildFile(fileRef: fileReference.reference)
-                )
+                targetFileReferences[target.productName] = fileReference
            }
        }

        for target in project.aggregateTargets {

-            let aggregateTarget = createObject(
-                id: target.name,
+            let aggregateTarget = addObject(
                PBXAggregateTarget(
                    name: target.name,
                    productName: target.name
@@ -167,10 +152,9 @@ public class PBXProjGenerator {
        try project.targets.forEach(generateTarget)
        try project.aggregateTargets.forEach(generateAggregateTarget)

-        let productGroup = createObject(
-            id: "Products",
+        let productGroup = addObject(
            PBXGroup(
-                children: Array(targetFileReferences.values),
+                children: targetFileReferences.valueArray,
                sourceTree: .group,
                name: "Products"
            )
@@ -179,34 +163,29 @@ public class PBXProjGenerator {

        if !carthageFrameworksByPlatform.isEmpty {
            var platforms: [PBXGroup] = []
-            var platformReferences: [String] = []
-            for (platform, fileReferences) in carthageFrameworksByPlatform {
-                let platformGroup: ObjectReference<PBXGroup> = createObject(
-                    id: "Carthage" + platform,
+            for (platform, files) in carthageFrameworksByPlatform {
+                let platformGroup: PBXGroup = addObject(
                    PBXGroup(
-                        children: fileReferences.sorted(),
+                        children: files.sorted { $0.nameOrPath < $1.nameOrPath },
                        sourceTree: .group,
                        path: platform
                    )
                )
-                platformReferences.append(platformGroup.reference)
-                platforms.append(platformGroup.object)
+                platforms.append(platformGroup)
            }
-            let carthageGroup = createObject(
-                id: "Carthage",
+            let carthageGroup = addObject(
                PBXGroup(
-                    children: platformReferences.sorted(),
+                    children: platforms,
                    sourceTree: .group,
                    name: "Carthage",
                    path: carthageBuildPath
                )
            )
-            frameworkFiles.append(carthageGroup.reference)
+            frameworkFiles.append(carthageGroup)
        }

        if !frameworkFiles.isEmpty {
-            let group = createObject(
-                id: "Frameworks",
+            let group = addObject(
                PBXGroup(
                    children: frameworkFiles,
                    sourceTree: .group,
@@ -216,90 +195,86 @@ public class PBXProjGenerator {
            derivedGroups.append(group)
        }

-        mainGroup.object.children = Array(sourceGenerator.rootGroups)
+        mainGroup.children = Array(sourceGenerator.rootGroups)
        sortGroups(group: mainGroup)
        // add derived groups at the end
        derivedGroups.forEach(sortGroups)
-        mainGroup.object.children += derivedGroups
-            .sorted { $0.object.nameOrPath.localizedStandardCompare($1.object.nameOrPath) == .orderedAscending }
-            .map { $0.reference }
+        mainGroup.children += derivedGroups
+            .sorted { $0.nameOrPath.localizedStandardCompare($1.nameOrPath) == .orderedAscending }
+            .map { $0 }

        let projectAttributes: [String: Any] = ["LastUpgradeCheck": project.xcodeVersion]
            .merged(project.attributes)
-            .merged(generateTargetAttributes() ?? [:])

        let knownRegions = sourceGenerator.knownRegions.sorted()
-        pbxProject.object.knownRegions = knownRegions.isEmpty ? ["en"] : knownRegions
-
-        let allTargets: [ObjectReference<PBXTarget>] = Array(targetObjects.values) + Array(targetAggregateObjects.values.map { ObjectReference(reference: $0.reference, object: $0.object) })
-        pbxProject.object.targets = allTargets
-            .sorted { $0.object.name < $1.object.name }
-            .map { $0.reference }
-        pbxProject.object.attributes = projectAttributes
+        pbxProject.knownRegions = knownRegions.isEmpty ? ["en"] : knownRegions

+        let allTargets: [PBXTarget] = Array(targetObjects.values) + Array(targetAggregateObjects.values)
+        pbxProject.targets = allTargets
+            .sorted { $0.name < $1.name }
+        pbxProject.attributes = projectAttributes
+        pbxProject.targetAttributes = generateTargetAttributes()
        return pbxProj
    }

    func generateAggregateTarget(_ target: AggregateTarget) throws {

-        let aggregateTarget = targetAggregateObjects[target.name]!.object
+        let aggregateTarget = targetAggregateObjects[target.name]!

-        let configs: [ObjectReference<XCBuildConfiguration>] = project.configs.map { config in
+        let configs: [XCBuildConfiguration] = project.configs.map { config in

            let buildSettings = project.getBuildSettings(settings: target.settings, config: config)

-            var baseConfigurationReference: String?
+            var baseConfiguration: PBXFileReference?
            if let configPath = target.configFiles[config.name] {
-                baseConfigurationReference = sourceGenerator.getContainedFileReference(path: project.basePath + configPath)
+                baseConfiguration = sourceGenerator.getContainedFileReference(path: project.basePath + configPath) as? PBXFileReference
            }
            let buildConfig = XCBuildConfiguration(
                name: config.name,
-                baseConfigurationReference: baseConfigurationReference,
+                baseConfiguration: baseConfiguration,
                buildSettings: buildSettings
            )
-            return createObject(id: config.name + target.name, buildConfig)
+            return addObject(buildConfig)
        }

-        let dependencies: [String] = target.targets.map { generateTargetDependency(from: target.name, to: $0).reference }
+        let dependencies = target.targets.map { generateTargetDependency(from: target.name, to: $0) }

-        let buildConfigList = createObject(id: target.name, XCConfigurationList(
-            buildConfigurations: configs.map { $0.reference },
+        let buildConfigList = addObject(XCConfigurationList(
+            buildConfigurations: configs,
            defaultConfigurationName: ""
        ))

-        var buildPhases: [String] = []
+        var buildPhases: [PBXBuildPhase] = []
        buildPhases += try target.buildScripts.map { try generateBuildScript(targetName: target.name, buildScript: $0) }

        aggregateTarget.buildPhases = buildPhases
-        aggregateTarget.buildConfigurationList = buildConfigList.reference
+        aggregateTarget.buildConfigurationList = buildConfigList
        aggregateTarget.dependencies = dependencies
    }

-    func generateTargetDependency(from: String, to target: String) -> ObjectReference<PBXTargetDependency> {
-        guard let targetReference = targetObjects[target]?.reference ?? targetAggregateObjects[target]?.reference else {
+    func generateTargetDependency(from: String, to target: String) -> PBXTargetDependency {
+        guard let targetObject = targetObjects[target] ?? targetAggregateObjects[target] else {
            fatalError("target not found")
        }
-        let targetProxy = createObject(
-            id: "\(from)-\(target)",
+        let targetProxy = addObject(
            PBXContainerItemProxy(
-                containerPortal: pbxProj.rootObject,
-                remoteGlobalIDString: targetReference,
+                containerPortal: pbxProj.rootObject!,
+                remoteGlobalID: targetObject,
                proxyType: .nativeTarget,
                remoteInfo: target
            )
        )

-        let targetDependency = createObject(
-            id: "\(from)-\(target)",
+        let targetDependency = addObject(
            PBXTargetDependency(
-                target: targetReference,
-                targetProxy: targetProxy.reference
+                target: targetObject,
+                targetProxy: targetProxy
            )
        )
        return targetDependency
    }

-    func generateBuildScript(targetName: String, buildScript: BuildScript) throws -> String {
+    func generateBuildScript(targetName: String, buildScript: BuildScript) throws -> PBXShellScriptBuildPhase {

        let shellScript: String
        switch buildScript.script {
@@ -310,47 +285,43 @@ public class PBXProjGenerator {
        }

        let shellScriptPhase = PBXShellScriptBuildPhase(
-            files: [],
            name: buildScript.name ?? "Run Script",
            inputPaths: buildScript.inputFiles,
            outputPaths: buildScript.outputFiles,
            shellPath: buildScript.shell ?? "/bin/sh",
-            shellScript: shellScript
+            shellScript: shellScript,
+            runOnlyForDeploymentPostprocessing: buildScript.runOnlyWhenInstalling,
+            showEnvVarsInLog: buildScript.showEnvVars
        )
-        shellScriptPhase.runOnlyForDeploymentPostprocessing = buildScript.runOnlyWhenInstalling
-        shellScriptPhase.showEnvVarsInLog = buildScript.showEnvVars
-        return createObject(id: String(describing: buildScript.name) + shellScript + targetName, shellScriptPhase).reference
+        return addObject(shellScriptPhase)
    }

-    func generateTargetAttributes() -> [String: Any]? {
+    func generateTargetAttributes() -> [PBXTarget: [String: Any]] {

-        var targetAttributes: [String: [String: Any]] = [:]
+        var targetAttributes: [PBXTarget: [String: Any]] = [:]

-        let uiTestTargets = pbxProj.objects.nativeTargets.objectReferences.filter { $0.object.productType == .uiTestBundle }
+        let uiTestTargets = pbxProj.nativeTargets.filter { $0.productType == .uiTestBundle }
        for uiTestTarget in uiTestTargets {

            // look up TEST_TARGET_NAME build setting
            func testTargetName(_ target: PBXTarget) -> String? {
-                guard let configurationList = target.buildConfigurationList else { return nil }
-                guard let buildConfigurationReferences = self.pbxProj.objects.configurationLists[configurationList]?.buildConfigurations else { return nil }
+                guard let buildConfigurations = target.buildConfigurationList?.buildConfigurations else { return nil }

-                let configs = buildConfigurationReferences
-                    .compactMap { ref in self.pbxProj.objects.buildConfigurations[ref] }
-
-                return configs
+                return buildConfigurations
                    .compactMap { $0.buildSettings["TEST_TARGET_NAME"] as? String }
                    .first
            }

-            guard let name = testTargetName(uiTestTarget.object) else { continue }
-            guard let target = self.pbxProj.objects.targets(named: name).first else { continue }
+            guard let name = testTargetName(uiTestTarget) else { continue }
+            guard let target = self.pbxProj.targets(named: name).first else { continue }

-            targetAttributes[uiTestTarget.reference, default: [:]].merge(["TestTargetID": target.reference])
+            // FIX: Can't set in xcproj 5.0+
+            targetAttributes[uiTestTarget, default: [:]].merge(["TestTargetID": target])
        }

-        func generateTargetAttributes(_ target: ProjectTarget, targetReference: String) {
+        func generateTargetAttributes(_ target: ProjectTarget, pbxTarget: PBXTarget) {
            if !target.attributes.isEmpty {
-                targetAttributes[targetReference, default: [:]].merge(target.attributes)
+                targetAttributes[pbxTarget, default: [:]].merge(target.attributes)
            }

            func getSingleBuildSetting(_ setting: String) -> String? {
@@ -367,7 +338,7 @@ public class PBXProjGenerator {

            func setTargetAttribute(attribute: String, buildSetting: String) {
                if let setting = getSingleBuildSetting(buildSetting) {
-                    targetAttributes[targetReference, default: [:]].merge([attribute: setting])
+                    targetAttributes[pbxTarget, default: [:]].merge([attribute: setting])
                }
            }

@@ -376,49 +347,39 @@ public class PBXProjGenerator {
        }

        for target in project.aggregateTargets {
-            guard let targetReference = targetAggregateObjects[target.name]?.reference else {
+            guard let pbxTarget = targetAggregateObjects[target.name] else {
                continue
            }
-            generateTargetAttributes(target, targetReference: targetReference)
+            generateTargetAttributes(target, pbxTarget: pbxTarget)
        }

        for target in project.targets {
-            guard let targetReference = targetObjects[target.name]?.reference else {
+            guard let pbxTarget = targetObjects[target.name] else {
                continue
            }
-            generateTargetAttributes(target, targetReference: targetReference)
+            generateTargetAttributes(target, pbxTarget: pbxTarget)
        }

-        return targetAttributes.isEmpty ? nil : ["TargetAttributes": targetAttributes]
+        return targetAttributes
    }

-    func sortGroups(group: ObjectReference<PBXGroup>) {
+    func sortGroups(group: PBXGroup) {
        // sort children
-        let children = group.object.children
-            .compactMap { reference -> ObjectReference<PBXFileElement>? in
-                guard let fileElement = pbxProj.objects.getFileElement(reference: reference) else {
-                    return nil
-                }
-                return ObjectReference(reference: reference, object: fileElement)
-            }
+        let children = group.children
            .sorted { child1, child2 in
-                let sortOrder1 = child1.object.getSortOrder(groupSortPosition: project.options.groupSortPosition)
-                let sortOrder2 = child2.object.getSortOrder(groupSortPosition: project.options.groupSortPosition)
+                let sortOrder1 = child1.getSortOrder(groupSortPosition: project.options.groupSortPosition)
+                let sortOrder2 = child2.getSortOrder(groupSortPosition: project.options.groupSortPosition)

                if sortOrder1 == sortOrder2 {
-                    return child1.object.nameOrPath.localizedStandardCompare(child2.object.nameOrPath) == .orderedAscending
+                    return child1.nameOrPath.localizedStandardCompare(child2.nameOrPath) == .orderedAscending
                } else {
                    return sortOrder1 < sortOrder2
                }
            }
-        group.object.children = children.map { $0.reference }.filter { $0 != group.reference }
+        group.children = children.filter { $0 != group }

        // sort sub groups
-        let childGroups = group.object.children.compactMap { reference -> ObjectReference<PBXGroup>? in
-            guard let group = pbxProj.objects.groups[reference] else {
-                return nil
-            }
-            return ObjectReference(reference: reference, object: group) }
+        let childGroups = group.children.compactMap { $0 as? PBXGroup }
        childGroups.forEach(sortGroups)
    }

@@ -428,19 +389,20 @@ public class PBXProjGenerator {
        let carthageDependencies = getAllCarthageDependencies(target: target)

        let sourceFiles = try sourceGenerator.getAllSourceFiles(targetType: target.type, sources: target.sources)
+            .sorted { $0.path.lastComponent < $1.path.lastComponent }

        var plistPath: Path?
        var searchForPlist = true
        var anyDependencyRequiresObjCLinking = false

-        var dependencies: [String] = []
-        var targetFrameworkBuildFiles: [String] = []
+        var dependencies: [PBXTargetDependency] = []
+        var targetFrameworkBuildFiles: [PBXBuildFile] = []
        var frameworkBuildPaths = Set<String>()
-        var copyFilesBuildPhasesFiles: [TargetSource.BuildPhase.CopyFilesSettings: [String]] = [:]
-        var copyFrameworksReferences: [String] = []
-        var copyResourcesReferences: [String] = []
-        var copyWatchReferences: [String] = []
-        var extensions: [String] = []
+        var copyFilesBuildPhasesFiles: [TargetSource.BuildPhase.CopyFilesSettings: [PBXBuildFile]] = [:]
+        var copyFrameworksReferences: [PBXBuildFile] = []
+        var copyResourcesReferences: [PBXBuildFile] = []
+        var copyWatchReferences: [PBXBuildFile] = []
+        var extensions: [PBXBuildFile] = []
        var carthageFrameworksToEmbed: [String] = []

        let targetDependencies = (target.transitivelyLinkDependencies ?? project.options.transitivelyLinkDependencies) ?
@@ -475,11 +437,11 @@ public class PBXProjGenerator {
            case .target:
                let dependencyTargetName = dependency.reference
                let targetDependency = generateTargetDependency(from: target.name, to: dependencyTargetName)
-                dependencies.append(targetDependency.reference)
+                dependencies.append(targetDependency)

                guard let dependencyTarget = project.getTarget(dependencyTargetName) else { continue }

-                let dependencyFileReference = targetFileReferences[dependencyTargetName]!
+                let dependencyFileReference = targetFileReferences[dependencyTarget.productName]!

                let dependecyLinkage = dependencyTarget.defaultLinkage
                let link = dependency.link ?? (
@@ -487,15 +449,11 @@ public class PBXProjGenerator {
                        || (dependecyLinkage == .static && target.type.isExecutable)
                )
                if link {
-                    let dependencyBuildFile = targetBuildFiles[dependencyTargetName]!
-                    let buildFile = createObject(
-                        id: dependencyBuildFile.reference + target.name,
-                        PBXBuildFile(
-                            fileRef: dependencyBuildFile.object.fileRef!,
-                            settings: getDependencyFrameworkSettings(dependency: dependency)
-                        )
+                    let dependencyFile = targetFileReferences[dependencyTarget.productName]!
+                    let buildFile = addObject(
+                        PBXBuildFile(file: dependencyFile, settings: getDependencyFrameworkSettings(dependency: dependency))
                    )
-                    targetFrameworkBuildFiles.append(buildFile.reference)
+                    targetFrameworkBuildFiles.append(buildFile)

                    if !anyDependencyRequiresObjCLinking
                        && dependencyTarget.requiresObjCLinking ?? (dependencyTarget.type == .staticLibrary) {
@@ -508,32 +466,31 @@ public class PBXProjGenerator {
                        || (target.type.isTest && (dependencyTarget.type.isFramework || dependencyTarget.type == .bundle))
                ))
                if embed {
-                    let embedFile = createObject(
-                        id: dependencyFileReference + target.name,
+                    let embedFile = addObject(
                        PBXBuildFile(
-                            fileRef: dependencyFileReference,
+                            file: dependencyFileReference,
                            settings: getEmbedSettings(dependency: dependency, codeSign: dependency.codeSign ?? !dependencyTarget.type.isExecutable)
                        )
                    )

                    if dependencyTarget.type.isExtension {
                        // embed app extension
-                        extensions.append(embedFile.reference)
+                        extensions.append(embedFile)
                    } else if dependencyTarget.type.isFramework {
-                        copyFrameworksReferences.append(embedFile.reference)
+                        copyFrameworksReferences.append(embedFile)
                    } else if dependencyTarget.type.isApp && dependencyTarget.platform == .watchOS {
-                        copyWatchReferences.append(embedFile.reference)
+                        copyWatchReferences.append(embedFile)
                    } else if dependencyTarget.type == .xpcService {
-                        copyFilesBuildPhasesFiles[.xpcServices, default: []].append(embedFile.reference)
+                        copyFilesBuildPhasesFiles[.xpcServices, default: []].append(embedFile)
                    } else {
-                        copyResourcesReferences.append(embedFile.reference)
+                        copyResourcesReferences.append(embedFile)
                    }
                }

            case .framework:
                guard target.type != .staticLibrary else { break }

-                let fileReference: String
+                let fileReference: PBXFileElement
                if dependency.implicit {
                    fileReference = sourceGenerator.getFileReference(
                        path: Path(dependency.reference),
@@ -547,25 +504,20 @@ public class PBXProjGenerator {
                    )
                }

-                let buildFile = createObject(
-                    id: "framework" + fileReference + target.name,
-                    PBXBuildFile(
-                        fileRef: fileReference,
-                        settings: getDependencyFrameworkSettings(dependency: dependency)
-                    )
+                let buildFile = addObject(
+                    PBXBuildFile(file: fileReference, settings: getDependencyFrameworkSettings(dependency: dependency))
                )

-                targetFrameworkBuildFiles.append(buildFile.reference)
+                targetFrameworkBuildFiles.append(buildFile)
                if !frameworkFiles.contains(fileReference) {
                    frameworkFiles.append(fileReference)
                }

                if embed {
-                    let embedFile = createObject(
-                        id: "framework embed" + fileReference + target.name,
-                        PBXBuildFile(fileRef: fileReference, settings: getEmbedSettings(dependency: dependency, codeSign: dependency.codeSign ?? true))
+                    let embedFile = addObject(
+                        PBXBuildFile(file: fileReference, settings: getEmbedSettings(dependency: dependency, codeSign: dependency.codeSign ?? true))
                    )
-                    copyFrameworksReferences.append(embedFile.reference)
+                    copyFrameworksReferences.append(embedFile)
                }

                let buildPath = Path(dependency.reference).parent().string.quoted
@@ -581,17 +533,13 @@ public class PBXProjGenerator {
                }
                let fileReference = sourceGenerator.getFileReference(path: frameworkPath, inPath: platformPath)

-                let buildFile = createObject(
-                    id: "carthage" + fileReference + target.name,
-                    PBXBuildFile(
-                        fileRef: fileReference,
-                        settings: getDependencyFrameworkSettings(dependency: dependency)
-                    )
+                let buildFile = addObject(
+                    PBXBuildFile(file: fileReference, settings: getDependencyFrameworkSettings(dependency: dependency))
                )

                carthageFrameworksByPlatform[target.platform.carthageDirectoryName, default: []].insert(fileReference)

-                targetFrameworkBuildFiles.append(buildFile.reference)
+                targetFrameworkBuildFiles.append(buildFile)

                // Embedding handled by iterating over `carthageDependencies` below
            }
@@ -611,39 +559,36 @@ public class PBXProjGenerator {

            if embed {
                if directlyEmbedCarthage {
-                    let embedFile = createObject(
-                        id: "carthage embed" + fileReference + target.name,
-                        PBXBuildFile(fileRef: fileReference, settings: getEmbedSettings(dependency: dependency, codeSign: dependency.codeSign ?? true))
+                    let embedFile = addObject(
+                        PBXBuildFile(file: fileReference, settings: getEmbedSettings(dependency: dependency, codeSign: dependency.codeSign ?? true))
                    )
-                    copyFrameworksReferences.append(embedFile.reference)
+                    copyFrameworksReferences.append(embedFile)
                } else {
                    carthageFrameworksToEmbed.append(dependency.reference)
                }
            }
        }

-        let fileReference = targetFileReferences[target.name]
-        var buildPhases: [String] = []
+        let fileReference = targetFileReferences[target.productName]
+        var buildPhases: [PBXBuildPhase] = []

-        func getBuildFilesForSourceFiles(_ sourceFiles: [SourceFile]) -> [String] {
-            let files = sourceFiles
+        func getBuildFilesForSourceFiles(_ sourceFiles: [SourceFile]) -> [PBXBuildFile] {
+            return sourceFiles
                .reduce(into: [SourceFile]()) { output, sourceFile in
-                    if !output.contains(where: { $0.fileReference == sourceFile.fileReference }) {
+                    if !output.contains(where: { $0.fileReference === sourceFile.fileReference }) {
                        output.append(sourceFile)
                    }
                }
-                .sorted { $0.path.lastComponent < $1.path.lastComponent }
-            return files.map { createObject(id: $0.fileReference + target.name, $0.buildFile) }
-                .map { $0.reference }
+                .map { addObject($0.buildFile) }
        }

-        func getBuildFilesForPhase(_ buildPhase: BuildPhase) -> [String] {
+        func getBuildFilesForPhase(_ buildPhase: BuildPhase) -> [PBXBuildFile] {
            let filteredSourceFiles = sourceFiles
                .filter { $0.buildPhase?.buildPhase == buildPhase }
            return getBuildFilesForSourceFiles(filteredSourceFiles)
        }

-        func getBuildFilesForCopyFilesPhases() -> [TargetSource.BuildPhase.CopyFilesSettings: [String]] {
+        func getBuildFilesForCopyFilesPhases() -> [TargetSource.BuildPhase.CopyFilesSettings: [PBXBuildFile]] {
            var sourceFilesByCopyFiles: [TargetSource.BuildPhase.CopyFilesSettings: [SourceFile]] = [:]
            for sourceFile in sourceFiles {
                guard case let .copyFiles(copyFilesSettings)? = sourceFile.buildPhase else { continue }
@@ -655,19 +600,23 @@ public class PBXProjGenerator {
        buildPhases += try target.prebuildScripts.map { try generateBuildScript(targetName: target.name, buildScript: $0) }

        let headersBuildPhaseFiles = getBuildFilesForPhase(.headers)
-        if !headersBuildPhaseFiles.isEmpty && (target.type == .framework || target.type == .dynamicLibrary) {
-            let headersBuildPhase = createObject(id: target.name, PBXHeadersBuildPhase(files: headersBuildPhaseFiles))
-            buildPhases.append(headersBuildPhase.reference)
+        if !headersBuildPhaseFiles.isEmpty {
+            if (target.type == .framework || target.type == .dynamicLibrary) {
+                let headersBuildPhase = addObject(PBXHeadersBuildPhase(files: headersBuildPhaseFiles))
+                buildPhases.append(headersBuildPhase)
+            } else {
+                headersBuildPhaseFiles.forEach { pbxProj.delete(object: $0) }
+            }
        }

        let sourcesBuildPhaseFiles = getBuildFilesForPhase(.sources)
-        let sourcesBuildPhase = createObject(id: target.name, PBXSourcesBuildPhase(files: sourcesBuildPhaseFiles))
-        buildPhases.append(sourcesBuildPhase.reference)
+        let sourcesBuildPhase = addObject(PBXSourcesBuildPhase(files: sourcesBuildPhaseFiles))
+        buildPhases.append(sourcesBuildPhase)

        let resourcesBuildPhaseFiles = getBuildFilesForPhase(.resources) + copyResourcesReferences
        if !resourcesBuildPhaseFiles.isEmpty {
-            let resourcesBuildPhase = createObject(id: target.name, PBXResourcesBuildPhase(files: resourcesBuildPhaseFiles))
-            buildPhases.append(resourcesBuildPhase.reference)
+            let resourcesBuildPhase = addObject(PBXResourcesBuildPhase(files: resourcesBuildPhaseFiles))
+            buildPhases.append(resourcesBuildPhase)
        }

        let swiftObjCInterfaceHeader = project.getCombinedBuildSetting("SWIFT_OBJC_INTERFACE_HEADER_NAME", target: target, config: project.configs[0]) as? String
@@ -678,10 +627,8 @@ public class PBXProjGenerator {

            let inputPaths = ["$(DERIVED_SOURCES_DIR)/$(SWIFT_OBJC_INTERFACE_HEADER_NAME)"]
            let outputPaths = ["$(BUILT_PRODUCTS_DIR)/include/$(PRODUCT_MODULE_NAME)/$(SWIFT_OBJC_INTERFACE_HEADER_NAME)"]
-            let script = createObject(
-                id: "Swift.h" + target.name,
+            let script = addObject(
                PBXShellScriptBuildPhase(
-                    files: [],
                    name: "Copy Swift Objective-C Interface Header",
                    inputPaths: inputPaths,
                    outputPaths: outputPaths,
@@ -689,14 +636,13 @@ public class PBXProjGenerator {
                    shellScript: "ditto \"${SCRIPT_INPUT_FILE_0}\" \"${SCRIPT_OUTPUT_FILE_0}\"\n"
                )
            )
-            buildPhases.append(script.reference)
+            buildPhases.append(script)
        }

        copyFilesBuildPhasesFiles.merge(getBuildFilesForCopyFilesPhases()) { $0 + $1 }
        if !copyFilesBuildPhasesFiles.isEmpty {
            for (copyFiles, buildPhaseFiles) in copyFilesBuildPhasesFiles {
-                let copyFilesBuildPhase = createObject(
-                    id: "copy files" + copyFiles.destination.rawValue + copyFiles.subpath + target.name,
+                let copyFilesBuildPhase = addObject(
                    PBXCopyFilesBuildPhase(
                        dstPath: copyFiles.subpath,
                        dstSubfolderSpec: copyFiles.destination.destination,
@@ -704,23 +650,21 @@ public class PBXProjGenerator {
                    )
                )

-                buildPhases.append(copyFilesBuildPhase.reference)
+                buildPhases.append(copyFilesBuildPhase)
            }
        }

        if !targetFrameworkBuildFiles.isEmpty {

-            let frameworkBuildPhase = createObject(
-                id: target.name,
+            let frameworkBuildPhase = addObject(
                PBXFrameworksBuildPhase(files: targetFrameworkBuildFiles)
            )
-            buildPhases.append(frameworkBuildPhase.reference)
+            buildPhases.append(frameworkBuildPhase)
        }

        if !extensions.isEmpty {

-            let copyFilesPhase = createObject(
-                id: "embed app extensions" + target.name,
+            let copyFilesPhase = addObject(
                PBXCopyFilesBuildPhase(
                    dstPath: "",
                    dstSubfolderSpec: .plugins,
@@ -729,14 +673,13 @@ public class PBXProjGenerator {
                )
            )

-            buildPhases.append(copyFilesPhase.reference)
+            buildPhases.append(copyFilesPhase)
        }

        copyFrameworksReferences += getBuildFilesForPhase(.frameworks)
        if !copyFrameworksReferences.isEmpty {

-            let copyFilesPhase = createObject(
-                id: "embed frameworks" + target.name,
+            let copyFilesPhase = addObject(
                PBXCopyFilesBuildPhase(
                    dstPath: "",
                    dstSubfolderSpec: .frameworks,
@@ -745,13 +688,12 @@ public class PBXProjGenerator {
                )
            )

-            buildPhases.append(copyFilesPhase.reference)
+            buildPhases.append(copyFilesPhase)
        }

        if !copyWatchReferences.isEmpty {

-            let copyFilesPhase = createObject(
-                id: "embed watch content" + target.name,
+            let copyFilesPhase = addObject(
                PBXCopyFilesBuildPhase(
                    dstPath: "$(CONTENTS_FOLDER_PATH)/Watch",
                    dstSubfolderSpec: .productsDirectory,
@@ -760,7 +702,7 @@ public class PBXProjGenerator {
                )
            )

-            buildPhases.append(copyFilesPhase.reference)
+            buildPhases.append(copyFilesPhase)
        }

        if !carthageFrameworksToEmbed.isEmpty {
@@ -770,10 +712,8 @@ public class PBXProjGenerator {
            let outputPaths = carthageFrameworksToEmbed
                .map { "$(BUILT_PRODUCTS_DIR)/$(FRAMEWORKS_FOLDER_PATH)/\($0)\($0.contains(".") ? "" : ".framework")" }
            let carthageExecutable = project.options.carthageExecutablePath ?? "carthage"
-            let carthageScript = createObject(
-                id: "Carthage" + target.name,
+            let carthageScript = addObject(
                PBXShellScriptBuildPhase(
-                    files: [],
                    name: "Carthage",
                    inputPaths: inputPaths,
                    outputPaths: outputPaths,
@@ -781,12 +721,11 @@ public class PBXProjGenerator {
                    shellScript: "\(carthageExecutable) copy-frameworks\n"
                )
            )
-            buildPhases.append(carthageScript.reference)
+            buildPhases.append(carthageScript)
        }

        let buildRules = target.buildRules.map { buildRule in
-            createObject(
-                id: "\(target.name)-\(buildRule.action)-\(buildRule.fileType)",
+            addObject(
                PBXBuildRule(
                    compilerSpec: buildRule.action.compilerSpec,
                    fileType: buildRule.fileType.fileType,
@@ -797,12 +736,12 @@ public class PBXProjGenerator {
                    outputFilesCompilerFlags: buildRule.outputFilesCompilerFlags,
                    script: buildRule.action.script
                )
-            ).reference
+            )
        }

        buildPhases += try target.postbuildScripts.map { try generateBuildScript(targetName: target.name, buildScript: $0) }

-        let configs: [ObjectReference<XCBuildConfiguration>] = project.configs.map { config in
+        let configs: [XCBuildConfiguration] = project.configs.map { config in
            var buildSettings = project.getTargetBuildSettings(target: target, config: config)

            // automatically set INFOPLIST_FILE path
@@ -876,32 +815,33 @@ public class PBXProjGenerator {
                }
            }

-            var baseConfigurationReference: String?
-            if let configPath = target.configFiles[config.name] {
-                baseConfigurationReference = sourceGenerator.getContainedFileReference(path: project.basePath + configPath)
+            var baseConfiguration: PBXFileReference?
+            if let configPath = target.configFiles[config.name],
+                let fileReference = sourceGenerator.getContainedFileReference(path: project.basePath + configPath) as? PBXFileReference {
+                baseConfiguration = fileReference
            }
            let buildConfig = XCBuildConfiguration(
                name: config.name,
-                baseConfigurationReference: baseConfigurationReference,
                buildSettings: buildSettings
            )
-            return createObject(id: config.name + target.name, buildConfig)
+            buildConfig.baseConfiguration = baseConfiguration
+            return addObject(buildConfig)
        }

-        let buildConfigList = createObject(id: target.name, XCConfigurationList(
-            buildConfigurations: configs.map { $0.reference },
+        let buildConfigList = addObject(XCConfigurationList(
+            buildConfigurations: configs,
            defaultConfigurationName: ""
        ))

-        let targetObject = targetObjects[target.name]!.object
+        let targetObject = targetObjects[target.name]!

        targetObject.name = target.name
-        targetObject.buildConfigurationList = buildConfigList.reference
+        targetObject.buildConfigurationList = buildConfigList
        targetObject.buildPhases = buildPhases
        targetObject.dependencies = dependencies
        targetObject.productName = target.name
        targetObject.buildRules = buildRules
-        targetObject.productReference = fileReference
+        targetObject.product = fileReference
        if !target.isLegacy {
            targetObject.productType = target.type
        }
@@ -943,7 +883,7 @@ public class PBXProjGenerator {
            if let target = projectTarget as? Target {
                for dependency in target.dependencies {
                    // don't overwrite frameworks, to allow top level ones to rule
-                    if frameworks.contains(reference: dependency.reference) {
+                    if frameworks[dependency.reference] != nil {
                        continue
                    }

@@ -987,7 +927,7 @@ public class PBXProjGenerator {

            for dependency in target.dependencies {
                // don't overwrite dependencies, to allow top level ones to rule
-                if dependencies.contains(reference: dependency.reference) {
+                if dependencies[dependency.reference] != nil {
                    continue
                }

@@ -2,7 +2,7 @@ import Foundation
 import JSONUtilities
 import PathKit
 import ProjectSpec
-import xcproj
+import xcodeproj
 import Yams

 public class ProjectGenerator {
@@ -42,8 +42,8 @@ public class ProjectGenerator {

        func getBuildEntry(_ buildTarget: Scheme.BuildTarget) -> XCScheme.BuildAction.Entry {

-            guard let targetReference = pbxProject.objects.targets(named: buildTarget.target).first else {
-                fatalError("Unable to find target named \"\(buildTarget.target)\" in \"PBXProj.objects.targets\"")
+            guard let pbxTarget = pbxProject.targets(named: buildTarget.target).first else {
+                fatalError("Unable to find target named \"\(buildTarget.target)\" in \"PBXProj.targets\"")
            }

            guard let buildableName =
@@ -53,7 +53,7 @@ public class ProjectGenerator {
            }
            let buildableReference = XCScheme.BuildableReference(
                referencedContainer: "container:\(project.name).xcodeproj",
-                blueprintIdentifier: targetReference.reference,
+                blueprint: pbxTarget,
                buildableName: buildableName,
                blueprintName: buildTarget.target
            )
@@ -2,7 +2,7 @@ import Foundation
 import JSONUtilities
 import PathKit
 import ProjectSpec
-import xcproj
+import xcodeproj
 import Yams

 extension Project {
@@ -1,6 +1,6 @@
 import Foundation
 import ProjectSpec
-import xcproj
+import xcodeproj

 public enum SettingsPresetFile {
    case config(ConfigType)
@@ -1,24 +1,24 @@
 import Foundation
 import PathKit
 import ProjectSpec
-import xcproj
+import xcodeproj

 struct SourceFile {
    let path: Path
-    let fileReference: String
+    let fileReference: PBXFileElement
    let buildFile: PBXBuildFile
    let buildPhase: TargetSource.BuildPhase?
 }

 class SourceGenerator {

-    var rootGroups: Set<String> = []
-    private var fileReferencesByPath: [String: String] = [:]
-    private var groupsByPath: [Path: ObjectReference<PBXGroup>] = [:]
-    private var variantGroupsByPath: [Path: ObjectReference<PBXVariantGroup>] = [:]
+    var rootGroups: Set<PBXFileElement> = []
+    private var fileReferencesByPath: [String: PBXFileElement] = [:]
+    private var groupsByPath: [Path: PBXGroup] = [:]
+    private var variantGroupsByPath: [Path: PBXVariantGroup] = [:]

    private let project: Project
-    var addObjectClosure: (String, PBXObject) -> String
+    var addObjectClosure: (PBXObject) -> Void
    var targetSourceExcludePaths: Set<Path> = []
    var defaultExcludedFiles = [
        ".DS_Store",
@@ -28,18 +28,14 @@ class SourceGenerator {

    private(set) var knownRegions: Set<String> = []

-    init(project: Project, addObjectClosure: @escaping (String, PBXObject) -> String) {
+    init(project: Project, addObjectClosure: @escaping (PBXObject) -> Void) {
        self.project = project
        self.addObjectClosure = addObjectClosure
    }

-    func addObject(id: String, _ object: PBXObject) -> String {
-        return addObjectClosure(id, object)
-    }
-
-    func createObject<T: PBXObject>(id: String, _ object: T) -> ObjectReference<T> {
-        let reference = addObject(id: id, object)
-        return ObjectReference(reference: reference, object: object)
+    func addObject<T: PBXObject>(_ object: T) -> T {
+        addObjectClosure(object)
+        return object
    }

    func getAllSourceFiles(targetType: PBXProductType, sources: [TargetSource]) throws -> [SourceFile] {
@@ -90,7 +86,7 @@ class SourceGenerator {
            settings["COMPILER_FLAGS"] = targetSource.compilerFlags.joined(separator: " ")
        }

-        let buildFile = PBXBuildFile(fileRef: fileReference, settings: settings.isEmpty ? nil : settings)
+        let buildFile = PBXBuildFile(file: fileReference, settings: settings.isEmpty ? nil : settings)
        return SourceFile(
            path: path,
            fileReference: fileReference,
@@ -99,7 +95,7 @@ class SourceGenerator {
        )
    }

-    func getContainedFileReference(path: Path) -> String {
+    func getContainedFileReference(path: Path) -> PBXFileElement {
        let createIntermediateGroups = project.options.createIntermediateGroups

        let parentPath = path.parent()
@@ -112,12 +108,12 @@ class SourceGenerator {
        )

        if createIntermediateGroups {
-            createIntermediaGroups(for: parentGroup.reference, at: parentPath)
+            createIntermediaGroups(for: parentGroup, at: parentPath)
        }
        return fileReference
    }

-    func getFileReference(path: Path, inPath: Path, name: String? = nil, sourceTree: PBXSourceTree = .group, lastKnownFileType: String? = nil) -> String {
+    func getFileReference(path: Path, inPath: Path, name: String? = nil, sourceTree: PBXSourceTree = .group, lastKnownFileType: String? = nil) -> PBXFileElement {
        let fileReferenceKey = path.string.lowercased()
        if let fileReference = fileReferencesByPath[fileReferenceKey] {
            return fileReference
@@ -127,7 +123,7 @@ class SourceGenerator {
            if fileReferencePath.string == fileReferenceName {
                fileReferenceName = nil
            }
-            let lastKnownFileType = lastKnownFileType ?? PBXFileReference.fileType(path: path)
+            let lastKnownFileType = lastKnownFileType ?? Xcode.fileType(path: path)

            if path.extension == "xcdatamodeld" {
                let versionedModels = (try? path.children()) ?? []
@@ -137,10 +133,9 @@ class SourceGenerator {
                    .filter { $0.extension == "xcdatamodel" }
                    .sorted { $0.string.localizedStandardCompare($1.string) == .orderedAscending }

-                let modelFileReference =
+                let modelFileReferences =
                    sortedPaths.map { path in
-                        createObject(
-                            id: path.byRemovingBase(path: project.basePath).string,
+                        addObject(
                            PBXFileReference(
                                sourceTree: .group,
                                lastKnownFileType: "wrapper.xcdatamodel",
@@ -151,23 +146,22 @@ class SourceGenerator {
                // If no current version path is found we fall back to alphabetical
                // order by taking the last item in the sortedPaths array
                let currentVersionPath = findCurrentCoreDataModelVersionPath(using: versionedModels) ?? sortedPaths.last
-                let currentVersion: ObjectReference<PBXFileReference>? = {
+                let currentVersion: PBXFileReference? = {
                    guard let indexOf = sortedPaths.index(where: { $0 == currentVersionPath }) else { return nil }
-                    return modelFileReference[indexOf]
+                    return modelFileReferences[indexOf]
                }()
-                let versionGroup = addObject(id: fileReferencePath.string, XCVersionGroup(
-                    currentVersion: currentVersion?.reference,
+                let versionGroup = addObject(XCVersionGroup(
+                    currentVersion: currentVersion,
                    path: fileReferencePath.string,
                    sourceTree: sourceTree,
                    versionGroupType: "wrapper.xcdatamodel",
-                    children: modelFileReference.map { $0.reference }
+                    children: modelFileReferences
                ))
                fileReferencesByPath[fileReferenceKey] = versionGroup
                return versionGroup
            } else {
                // For all extensions other than `xcdatamodeld`
-                let fileReference = createObject(
-                    id: path.byRemovingBase(path: project.basePath).string,
+                let fileReference = addObject(
                    PBXFileReference(
                        sourceTree: sourceTree,
                        name: fileReferenceName,
@@ -175,8 +169,8 @@ class SourceGenerator {
                        path: fileReferencePath.string
                    )
                )
-                fileReferencesByPath[fileReferenceKey] = fileReference.reference
-                return fileReference.reference
+                fileReferencesByPath[fileReferenceKey] = fileReference
+                return fileReference
            }
        }
    }
@@ -207,12 +201,16 @@ class SourceGenerator {

    /// Create a group or return an existing one at the path.
    /// Any merged children are added to a new group or merged into an existing one.
-    private func getGroup(path: Path, name: String? = nil, mergingChildren children: [String], createIntermediateGroups: Bool, isBaseGroup: Bool) -> ObjectReference<PBXGroup> {
-        let groupReference: ObjectReference<PBXGroup>
+    private func getGroup(path: Path, name: String? = nil, mergingChildren children: [PBXFileElement], createIntermediateGroups: Bool, isBaseGroup: Bool) -> PBXGroup {
+        let groupReference: PBXGroup

        if let cachedGroup = groupsByPath[path] {
-            // only add the children that aren't already in the cachedGroup
-            cachedGroup.object.children = Array(Set(cachedGroup.object.children + children))
+            for child in children {
+                // only add the children that aren't already in the cachedGroup
+                if !cachedGroup.children.contains(child) {
+                    cachedGroup.children.append(child)
+                }
+            }
            groupReference = cachedGroup
        } else {

@@ -235,28 +233,27 @@ class SourceGenerator {
                name: groupName != groupPath ? groupName : nil,
                path: groupPath
            )
-            groupReference = createObject(id: path.byRemovingBase(path: project.basePath).string, group)
+            groupReference = addObject(group)
            groupsByPath[path] = groupReference

            if isTopLevelGroup {
-                rootGroups.insert(groupReference.reference)
+                rootGroups.insert(groupReference)
            }
        }
        return groupReference
    }

    /// Creates a variant group or returns an existing one at the path
-    private func getVariantGroup(path: Path, inPath: Path) -> ObjectReference<PBXVariantGroup> {
-        let variantGroup: ObjectReference<PBXVariantGroup>
+    private func getVariantGroup(path: Path, inPath: Path) -> PBXVariantGroup {
+        let variantGroup: PBXVariantGroup
        if let cachedGroup = variantGroupsByPath[path] {
            variantGroup = cachedGroup
        } else {
            let group = PBXVariantGroup(
-                children: [],
                sourceTree: .group,
                name: path.lastComponent
            )
-            variantGroup = createObject(id: path.byRemovingBase(path: project.basePath).string, group)
+            variantGroup = addObject(group)
            variantGroupsByPath[path] = variantGroup
        }
        return variantGroup
@@ -305,27 +302,24 @@ class SourceGenerator {

    /// creates all the source files and groups they belong to for a given targetSource
    private func getGroupSources(targetType: PBXProductType, targetSource: TargetSource, path: Path, isBaseGroup: Bool)
-        throws -> (sourceFiles: [SourceFile], groups: [ObjectReference<PBXGroup>]) {
+        throws -> (sourceFiles: [SourceFile], groups: [PBXGroup]) {

        let children = try getSourceChildren(targetSource: targetSource, dirPath: path)

        let directories = children
            .filter { $0.isDirectory && $0.extension == nil && $0.extension != "lproj" }
-            .sorted { $0.lastComponent < $1.lastComponent }

        let filePaths = children
            .filter { $0.isFile || $0.extension != nil && $0.extension != "lproj" }
-            .sorted { $0.lastComponent < $1.lastComponent }

        let localisedDirectories = children
            .filter { $0.extension == "lproj" }
-            .sorted { $0.lastComponent < $1.lastComponent }

-        var groupChildren: [String] = filePaths.map { getFileReference(path: $0, inPath: path) }
+        var groupChildren: [PBXFileElement] = filePaths.map { getFileReference(path: $0, inPath: path) }
        var allSourceFiles: [SourceFile] = filePaths.map {
            generateSourceFile(targetType: targetType, targetSource: targetSource, path: $0)
        }
-        var groups: [ObjectReference<PBXGroup>] = []
+        var groups: [PBXGroup] = []

        for path in directories {
            let subGroups = try getGroupSources(targetType: targetType, targetSource: targetSource, path: path, isBaseGroup: false)
@@ -336,11 +330,11 @@ class SourceGenerator {

            allSourceFiles += subGroups.sourceFiles

-            guard let first = subGroups.groups.first else {
+            guard let firstGroup = subGroups.groups.first else {
                continue
            }

-            groupChildren.append(first.reference)
+            groupChildren.append(firstGroup)
            groups += subGroups.groups
        }

@@ -363,13 +357,13 @@ class SourceGenerator {
                .filter(isIncludedPath)
                .sorted() {
                let variantGroup = getVariantGroup(path: filePath, inPath: path)
-                groupChildren.append(variantGroup.reference)
-                baseLocalisationVariantGroups.append(variantGroup.object)
+                groupChildren.append(variantGroup)
+                baseLocalisationVariantGroups.append(variantGroup)

                let sourceFile = SourceFile(
                    path: filePath,
-                    fileReference: variantGroup.reference,
-                    buildFile: PBXBuildFile(fileRef: variantGroup.reference),
+                    fileReference: variantGroup,
+                    buildFile: PBXBuildFile(file: variantGroup),
                    buildPhase: .resources
                )
                allSourceFiles.append(sourceFile)
@@ -407,7 +401,7 @@ class SourceGenerator {
                    let sourceFile = SourceFile(
                        path: filePath,
                        fileReference: fileReference,
-                        buildFile: PBXBuildFile(fileRef: fileReference),
+                        buildFile: PBXBuildFile(file: fileReference),
                        buildPhase: .resources
                    )
                    allSourceFiles.append(sourceFile)
@@ -423,7 +417,7 @@ class SourceGenerator {
            isBaseGroup: isBaseGroup
        )
        if project.options.createIntermediateGroups {
-            createIntermediaGroups(for: group.reference, at: path)
+            createIntermediaGroups(for: group, at: path)
        }

        groups.insert(group, at: 0)
@@ -440,7 +434,7 @@ class SourceGenerator {
        let createIntermediateGroups = project.options.createIntermediateGroups

        var sourceFiles: [SourceFile] = []
-        let sourceReference: String
+        let sourceReference: PBXFileElement
        var sourcePath = path
        switch type {
        case .folder:
@@ -481,7 +475,7 @@ class SourceGenerator {
            } else {
                let parentGroup = getGroup(path: parentPath, mergingChildren: [fileReference], createIntermediateGroups: createIntermediateGroups, isBaseGroup: true)
                sourcePath = parentPath
-                sourceReference = parentGroup.reference
+                sourceReference = parentGroup
            }
            sourceFiles.append(sourceFile)

@@ -489,11 +483,11 @@ class SourceGenerator {
            let (groupSourceFiles, groups) = try getGroupSources(targetType: targetType, targetSource: targetSource, path: path, isBaseGroup: true)
            let group = groups.first!
            if let name = targetSource.name {
-                group.object.name = name
+                group.name = name
            }

            sourceFiles += groupSourceFiles
-            sourceReference = group.reference
+            sourceReference = group
        }

        if createIntermediateGroups {
@@ -504,7 +498,7 @@ class SourceGenerator {
    }

    // Add groups for all parents recursively
-    private func createIntermediaGroups(for groupReference: String, at path: Path) {
+    private func createIntermediaGroups(for fileElement: PBXFileElement, at path: Path) {

        let parentPath = path.parent()
        guard parentPath != project.basePath && path.string.contains(project.basePath.string) else {
@@ -513,10 +507,10 @@ class SourceGenerator {
        }

        let hasParentGroup = groupsByPath[parentPath] != nil
-        let parentGroup = getGroup(path: parentPath, mergingChildren: [groupReference], createIntermediateGroups: true, isBaseGroup: false)
+        let parentGroup = getGroup(path: parentPath, mergingChildren: [fileElement], createIntermediateGroups: true, isBaseGroup: false)

        if !hasParentGroup {
-            createIntermediaGroups(for: parentGroup.reference, at: parentPath)
+            createIntermediaGroups(for: parentGroup, at: parentPath)
        }
    }

@@ -1,5 +1,6 @@
 import Foundation
-import xcproj
+import xcodeproj
+import PathKit

 extension PBXFileElement {

@@ -11,8 +12,8 @@ extension PBXFileElement {
 extension PBXProj {

    public func printGroups() -> String {
-        guard let project = objects.projects.first?.value,
-            let mainGroup = objects.groups.getReference(project.mainGroup) else {
+        guard let project = projects.first,
+            let mainGroup = project.mainGroup else {
            return ""
        }
        return printGroup(group: mainGroup)
@@ -20,17 +21,31 @@ extension PBXProj {

    public func printGroup(group: PBXGroup) -> String {
        var string = group.nameOrPath
-        for reference in group.children {
-            if let group = objects.groups.getReference(reference) {
+        for child in group.children {
+            if let group = child as? PBXGroup {
                string += "\n 📁  " + printGroup(group: group).replacingOccurrences(of: "\n ", with: "\n    ")
-            } else if let fileReference = objects.fileReferences.getReference(reference) {
+            } else if let fileReference = child as? PBXFileReference {
                string += "\n 📄  " + fileReference.nameOrPath
-            } else if let variantGroup = objects.variantGroups.getReference(reference) {
+            } else if let variantGroup = child as? PBXVariantGroup {
                string += "\n 🌎  " + variantGroup.nameOrPath
-            } else if let versionGroup = objects.versionGroups.getReference(reference) {
+            } else if let versionGroup = child as? XCVersionGroup {
                string += "\n 🔢  " + versionGroup.nameOrPath
            }
        }
        return string
    }
 }
+
+extension Dictionary {
+
+    public var valueArray: Array<Value> {
+        return Array(values)
+    }
+}
+
+extension Xcode {
+
+    public static func fileType(path: Path) -> String? {
+        return path.extension.flatMap { Xcode.filetype(extension: $0) }
+    }
+}
@@ -14,7 +14,7 @@
            buildForAnalyzing = "YES">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_825232110500"
+               BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
               BuildableName = "App_iOS.app"
               BlueprintName = "App_iOS"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -33,7 +33,7 @@
            skipped = "NO">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_783122899910"
+               BlueprintIdentifier = "NT_193BAF154270D1C21E269EDF2A1BD3F6"
               BuildableName = "App_iOS_Tests.xctest"
               BlueprintName = "App_iOS_Tests"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -43,7 +43,7 @@
            skipped = "NO">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_123503999387"
+               BlueprintIdentifier = "NT_D4BAEEEC88124103C8DFF41FCE206DCE"
               BuildableName = "App_iOS_UITests.xctest"
               BlueprintName = "App_iOS_UITests"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -53,21 +53,21 @@
      <MacroExpansion>
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_825232110500"
+            BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
            BuildableName = "App_iOS.app"
            BlueprintName = "App_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
         </BuildableReference>
      </MacroExpansion>
      <CommandLineArguments>
-         <CommandLineArgument
-            argument = "MyEnabledArgument"
-            isEnabled = "YES">
-         </CommandLineArgument>
         <CommandLineArgument
            argument = "MyDisabledArgument"
            isEnabled = "NO">
         </CommandLineArgument>
+         <CommandLineArgument
+            argument = "MyEnabledArgument"
+            isEnabled = "YES">
+         </CommandLineArgument>
      </CommandLineArguments>
      <AdditionalOptions>
      </AdditionalOptions>
@@ -86,21 +86,21 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_825232110500"
+            BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
            BuildableName = "App_iOS.app"
            BlueprintName = "App_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
         </BuildableReference>
      </BuildableProductRunnable>
      <CommandLineArguments>
-         <CommandLineArgument
-            argument = "MyEnabledArgument"
-            isEnabled = "YES">
-         </CommandLineArgument>
         <CommandLineArgument
            argument = "MyDisabledArgument"
            isEnabled = "NO">
         </CommandLineArgument>
+         <CommandLineArgument
+            argument = "MyEnabledArgument"
+            isEnabled = "YES">
+         </CommandLineArgument>
      </CommandLineArguments>
      <AdditionalOptions>
      </AdditionalOptions>
@@ -115,21 +115,21 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_825232110500"
+            BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
            BuildableName = "App_iOS.app"
            BlueprintName = "App_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
         </BuildableReference>
      </BuildableProductRunnable>
      <CommandLineArguments>
-         <CommandLineArgument
-            argument = "MyEnabledArgument"
-            isEnabled = "YES">
-         </CommandLineArgument>
         <CommandLineArgument
            argument = "MyDisabledArgument"
            isEnabled = "NO">
         </CommandLineArgument>
+         <CommandLineArgument
+            argument = "MyEnabledArgument"
+            isEnabled = "YES">
+         </CommandLineArgument>
      </CommandLineArguments>
   </ProfileAction>
   <AnalyzeAction
@@ -14,7 +14,7 @@
            buildForAnalyzing = "YES">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_825232110500"
+               BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
               BuildableName = "App_iOS.app"
               BlueprintName = "App_iOS"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -33,7 +33,7 @@
            skipped = "NO">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_783122899910"
+               BlueprintIdentifier = "NT_193BAF154270D1C21E269EDF2A1BD3F6"
               BuildableName = "App_iOS_Tests.xctest"
               BlueprintName = "App_iOS_Tests"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -43,7 +43,7 @@
            skipped = "NO">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_123503999387"
+               BlueprintIdentifier = "NT_D4BAEEEC88124103C8DFF41FCE206DCE"
               BuildableName = "App_iOS_UITests.xctest"
               BlueprintName = "App_iOS_UITests"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -53,21 +53,21 @@
      <MacroExpansion>
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_825232110500"
+            BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
            BuildableName = "App_iOS.app"
            BlueprintName = "App_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
         </BuildableReference>
      </MacroExpansion>
      <CommandLineArguments>
-         <CommandLineArgument
-            argument = "MyEnabledArgument"
-            isEnabled = "YES">
-         </CommandLineArgument>
         <CommandLineArgument
            argument = "MyDisabledArgument"
            isEnabled = "NO">
         </CommandLineArgument>
+         <CommandLineArgument
+            argument = "MyEnabledArgument"
+            isEnabled = "YES">
+         </CommandLineArgument>
      </CommandLineArguments>
      <AdditionalOptions>
      </AdditionalOptions>
@@ -86,21 +86,21 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_825232110500"
+            BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
            BuildableName = "App_iOS.app"
            BlueprintName = "App_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
         </BuildableReference>
      </BuildableProductRunnable>
      <CommandLineArguments>
-         <CommandLineArgument
-            argument = "MyEnabledArgument"
-            isEnabled = "YES">
-         </CommandLineArgument>
         <CommandLineArgument
            argument = "MyDisabledArgument"
            isEnabled = "NO">
         </CommandLineArgument>
+         <CommandLineArgument
+            argument = "MyEnabledArgument"
+            isEnabled = "YES">
+         </CommandLineArgument>
      </CommandLineArguments>
      <AdditionalOptions>
      </AdditionalOptions>
@@ -115,21 +115,21 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_825232110500"
+            BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
            BuildableName = "App_iOS.app"
            BlueprintName = "App_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
         </BuildableReference>
      </BuildableProductRunnable>
      <CommandLineArguments>
-         <CommandLineArgument
-            argument = "MyEnabledArgument"
-            isEnabled = "YES">
-         </CommandLineArgument>
         <CommandLineArgument
            argument = "MyDisabledArgument"
            isEnabled = "NO">
         </CommandLineArgument>
+         <CommandLineArgument
+            argument = "MyEnabledArgument"
+            isEnabled = "YES">
+         </CommandLineArgument>
      </CommandLineArguments>
   </ProfileAction>
   <AnalyzeAction
@@ -14,7 +14,7 @@
            buildForAnalyzing = "YES">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_825232110500"
+               BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
               BuildableName = "App_iOS.app"
               BlueprintName = "App_iOS"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -33,7 +33,7 @@
            skipped = "NO">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_783122899910"
+               BlueprintIdentifier = "NT_193BAF154270D1C21E269EDF2A1BD3F6"
               BuildableName = "App_iOS_Tests.xctest"
               BlueprintName = "App_iOS_Tests"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -43,7 +43,7 @@
            skipped = "NO">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_123503999387"
+               BlueprintIdentifier = "NT_D4BAEEEC88124103C8DFF41FCE206DCE"
               BuildableName = "App_iOS_UITests.xctest"
               BlueprintName = "App_iOS_UITests"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -53,21 +53,21 @@
      <MacroExpansion>
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_825232110500"
+            BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
            BuildableName = "App_iOS.app"
            BlueprintName = "App_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
         </BuildableReference>
      </MacroExpansion>
      <CommandLineArguments>
-         <CommandLineArgument
-            argument = "MyEnabledArgument"
-            isEnabled = "YES">
-         </CommandLineArgument>
         <CommandLineArgument
            argument = "MyDisabledArgument"
            isEnabled = "NO">
         </CommandLineArgument>
+         <CommandLineArgument
+            argument = "MyEnabledArgument"
+            isEnabled = "YES">
+         </CommandLineArgument>
      </CommandLineArguments>
      <AdditionalOptions>
      </AdditionalOptions>
@@ -86,21 +86,21 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_825232110500"
+            BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
            BuildableName = "App_iOS.app"
            BlueprintName = "App_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
         </BuildableReference>
      </BuildableProductRunnable>
      <CommandLineArguments>
-         <CommandLineArgument
-            argument = "MyEnabledArgument"
-            isEnabled = "YES">
-         </CommandLineArgument>
         <CommandLineArgument
            argument = "MyDisabledArgument"
            isEnabled = "NO">
         </CommandLineArgument>
+         <CommandLineArgument
+            argument = "MyEnabledArgument"
+            isEnabled = "YES">
+         </CommandLineArgument>
      </CommandLineArguments>
      <AdditionalOptions>
      </AdditionalOptions>
@@ -115,21 +115,21 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_825232110500"
+            BlueprintIdentifier = "NT_BEB0891E36797FE2214A0A9D516D408D"
            BuildableName = "App_iOS.app"
            BlueprintName = "App_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
         </BuildableReference>
      </BuildableProductRunnable>
      <CommandLineArguments>
-         <CommandLineArgument
-            argument = "MyEnabledArgument"
-            isEnabled = "YES">
-         </CommandLineArgument>
         <CommandLineArgument
            argument = "MyDisabledArgument"
            isEnabled = "NO">
         </CommandLineArgument>
+         <CommandLineArgument
+            argument = "MyEnabledArgument"
+            isEnabled = "YES">
+         </CommandLineArgument>
      </CommandLineArguments>
   </ProfileAction>
   <AnalyzeAction
@@ -14,7 +14,7 @@
            buildForAnalyzing = "YES">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_324671077936"
+               BlueprintIdentifier = "NT_38A9FE87056942A2746E0FF025B52A91"
               BuildableName = "App_watchOS.app"
               BlueprintName = "App_watchOS"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -32,7 +32,7 @@
      <MacroExpansion>
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_324671077936"
+            BlueprintIdentifier = "NT_38A9FE87056942A2746E0FF025B52A91"
            BuildableName = "App_watchOS.app"
            BlueprintName = "App_watchOS"
            ReferencedContainer = "container:Project.xcodeproj">
@@ -57,7 +57,7 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_324671077936"
+            BlueprintIdentifier = "NT_38A9FE87056942A2746E0FF025B52A91"
            BuildableName = "App_watchOS.app"
            BlueprintName = "App_watchOS"
            ReferencedContainer = "container:Project.xcodeproj">
@@ -78,7 +78,7 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_324671077936"
+            BlueprintIdentifier = "NT_38A9FE87056942A2746E0FF025B52A91"
            BuildableName = "App_watchOS.app"
            BlueprintName = "App_watchOS"
            ReferencedContainer = "container:Project.xcodeproj">
@@ -14,7 +14,7 @@
               <EnvironmentBuildable>
                  <BuildableReference
                     BuildableIdentifier = "primary"
-                     BlueprintIdentifier = "NT_472296042419"
+                     BlueprintIdentifier = "NT_7D108AE86BED8C9CCF52C2646FA4C5DE"
                     BuildableName = "Framework.framework"
                     BlueprintName = "Framework_iOS"
                     ReferencedContainer = "container:Project.xcodeproj">
@@ -32,7 +32,7 @@
            buildForAnalyzing = "YES">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_472296042419"
+               BlueprintIdentifier = "NT_7D108AE86BED8C9CCF52C2646FA4C5DE"
               BuildableName = "Framework.framework"
               BlueprintName = "Framework_iOS"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -50,7 +50,7 @@
      <MacroExpansion>
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_472296042419"
+            BlueprintIdentifier = "NT_7D108AE86BED8C9CCF52C2646FA4C5DE"
            BuildableName = "Framework.framework"
            BlueprintName = "Framework_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
@@ -72,7 +72,7 @@
      <MacroExpansion>
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_472296042419"
+            BlueprintIdentifier = "NT_7D108AE86BED8C9CCF52C2646FA4C5DE"
            BuildableName = "Framework.framework"
            BlueprintName = "Framework_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
@@ -101,7 +101,7 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_472296042419"
+            BlueprintIdentifier = "NT_7D108AE86BED8C9CCF52C2646FA4C5DE"
            BuildableName = "Framework.framework"
            BlueprintName = "Framework_iOS"
            ReferencedContainer = "container:Project.xcodeproj">
@@ -14,7 +14,7 @@
            buildForAnalyzing = "YES">
            <BuildableReference
               BuildableIdentifier = "primary"
-               BlueprintIdentifier = "NT_935153865209"
+               BlueprintIdentifier = "NT_6BD068FAAC6AA35C090C48147B94EC6E"
               BuildableName = "iMessageApp.app"
               BlueprintName = "iMessageApp"
               ReferencedContainer = "container:Project.xcodeproj">
@@ -32,7 +32,7 @@
      <MacroExpansion>
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_935153865209"
+            BlueprintIdentifier = "NT_6BD068FAAC6AA35C090C48147B94EC6E"
            BuildableName = "iMessageApp.app"
            BlueprintName = "iMessageApp"
            ReferencedContainer = "container:Project.xcodeproj">
@@ -57,7 +57,7 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_935153865209"
+            BlueprintIdentifier = "NT_6BD068FAAC6AA35C090C48147B94EC6E"
            BuildableName = "iMessageApp.app"
            BlueprintName = "iMessageApp"
            ReferencedContainer = "container:Project.xcodeproj">
@@ -78,7 +78,7 @@
         runnableDebuggingMode = "0">
         <BuildableReference
            BuildableIdentifier = "primary"
-            BlueprintIdentifier = "NT_935153865209"
+            BlueprintIdentifier = "NT_6BD068FAAC6AA35C090C48147B94EC6E"
            BuildableName = "iMessageApp.app"
            BlueprintName = "iMessageApp"
            ReferencedContainer = "container:Project.xcodeproj">
@@ -2,7 +2,7 @@ import PathKit
 import ProjectSpec
 import Spectre
 import XcodeGenKit
-import xcproj
+import xcodeproj
 import XCTest
 import Yams

@@ -34,10 +34,10 @@ extension PBXProj {
        func validateGroup(_ group: PBXGroup) throws {
            let hasDuplicatedChildren = group.children.count != Set(group.children).count
            if hasDuplicatedChildren {
-                throw failure("Group \"\(group.nameOrPath)\" has duplicated children:\n - \(group.children.sorted().joined(separator: "\n - "))")
+                throw failure("Group \"\(group.nameOrPath)\" has duplicated children:\n - \(group.children.map { String(describing: $0) }.joined(separator: "\n - "))")
            }
            for child in group.children {
-                if let group = objects.groups.getReference(child) {
+                if let group = child as? PBXGroup {
                    try validateGroup(group)
                }
            }
@@ -1,5 +1,5 @@
 import XcodeGenKit
-import xcproj
+import xcodeproj
 import Foundation
 import XCTest
 import ProjectSpec
@@ -22,6 +22,7 @@ class GeneratedPerformanceTests: XCTestCase {
        let generator = ProjectGenerator(project: project)
        let xcodeProject = try generator.generateXcodeProject()
        self.measure {
+            xcodeProject.pbxproj.invalidateUUIDs()
            try! xcodeProject.write(path: project.projectPath)
        }
    }
@@ -50,6 +51,7 @@ class FixturePerformanceTests: XCTestCase {
        let generator = ProjectGenerator(project: project)
        let xcodeProject = try generator.generateXcodeProject()
        self.measure {
+            xcodeProject.pbxproj.invalidateUUIDs()
            try! xcodeProject.write(path: project.projectPath)
        }
    }
@@ -2,7 +2,7 @@ import PathKit
 import ProjectSpec
 import Spectre
 import XcodeGenKit
-import xcproj
+import xcodeproj
 import XCTest

 class ProjectFixtureTests: XCTestCase {
@@ -18,12 +18,12 @@ class ProjectFixtureTests: XCTestCase {
            $0.it("generates variant group") {
                guard let xcodeProject = xcodeProject else { return }

-                func getFileReferences(_ path: String) -> [ObjectReference<PBXFileReference>] {
-                    return xcodeProject.pbxproj.objects.fileReferences.objectReferences.filter { $0.object.path == path }
+                func getFileReferences(_ path: String) -> [PBXFileReference] {
+                    return xcodeProject.pbxproj.fileReferences.filter { $0.path == path }
                }

                func getVariableGroups(_ name: String?) -> [PBXVariantGroup] {
-                    return xcodeProject.pbxproj.objects.variantGroups.referenceValues.filter { $0.name == name }
+                    return xcodeProject.pbxproj.variantGroups.filter { $0.name == name }
                }

                let resourceName = "LocalizedStoryboard.storyboard"
@@ -35,13 +35,13 @@ class ProjectFixtureTests: XCTestCase {
                do {
                    let refs = getFileReferences(baseResource)
                    try expect(refs.count) == 1
-                    try expect(variableGroup.children.filter { $0 == refs.first?.reference }.count) == 1
+                    try expect(variableGroup.children.filter { $0 == refs.first }.count) == 1
                }

                do {
                    let refs = getFileReferences(localizedResource)
                    try expect(refs.count) == 1
-                    try expect(variableGroup.children.filter { $0 == refs.first?.reference }.count) == 1
+                    try expect(variableGroup.children.filter { $0 == refs.first }.count) == 1
                }
            }

@@ -2,7 +2,7 @@ import PathKit
 import ProjectSpec
 import Spectre
 import XcodeGenKit
-import xcproj
+import xcodeproj
 import XCTest
 import Yams

@@ -47,11 +47,9 @@ class ProjectGeneratorTests: XCTestCase {
                let options = SpecOptions(bundleIdPrefix: "com.test")
                let project = Project(basePath: "", name: "test", targets: [framework], options: options)
                let pbxProj = try project.generatePbxProj()
-                guard let target = pbxProj.objects.nativeTargets.first?.value,
+                guard let target = pbxProj.nativeTargets.first,
                    let buildConfigList = target.buildConfigurationList,
-                    let buildConfigs = pbxProj.objects.configurationLists.getReference(buildConfigList),
-                    let buildConfigReference = buildConfigs.buildConfigurations.first,
-                    let buildConfig = pbxProj.objects.buildConfigurations.getReference(buildConfigReference) else {
+                    let buildConfig = buildConfigList.buildConfigurations.first else {
                    throw failure("Build Config not found")
                }
                try expect(buildConfig.buildSettings["PRODUCT_BUNDLE_IDENTIFIER"] as? String) == "com.test.MyFramework"
@@ -61,7 +59,7 @@ class ProjectGeneratorTests: XCTestCase {
                let options = SpecOptions(settingPresets: .none)
                let project = Project(basePath: "", name: "test", targets: [framework], options: options)
                let pbxProj = try project.generatePbxProj()
-                let allSettings = pbxProj.objects.buildConfigurations.referenceValues.reduce([:]) { $0.merged($1.buildSettings) }.keys.sorted()
+                let allSettings = pbxProj.buildConfigurations.reduce([:]) { $0.merged($1.buildSettings) }.keys.sorted()
                try expect(allSettings) == ["SETTING_2"]
            }

@@ -69,7 +67,7 @@ class ProjectGeneratorTests: XCTestCase {
                let options = SpecOptions(developmentLanguage: "de")
                let project = Project(basePath: "", name: "test", options: options)
                let pbxProj = try project.generatePbxProj()
-                guard let pbxProject = pbxProj.objects.projects.first?.value else {
+                guard let pbxProject = pbxProj.projects.first else {
                    throw failure("Could't find PBXProject")
                }
                try expect(pbxProject.developmentRegion) == "de"
@@ -98,8 +96,8 @@ class ProjectGeneratorTests: XCTestCase {
                let project = Project(basePath: "", name: "test", configs: [Config(name: "Aconfig"), Config(name: "Bconfig")], targets: [framework], options: options)
                let pbxProject = try project.generatePbxProj()

-                guard let projectConfigListReference = pbxProject.objects.projects.values.first?.buildConfigurationList,
-                    let defaultConfigurationName = pbxProject.objects.configurationLists[projectConfigListReference]?.defaultConfigurationName
+                guard let projectConfigList = pbxProject.projects.first?.buildConfigurationList,
+                    let defaultConfigurationName = projectConfigList.defaultConfigurationName
                else {
                    throw failure("Default configuration name not found")
                }
@@ -115,7 +113,7 @@ class ProjectGeneratorTests: XCTestCase {
            $0.it("generates config defaults") {
                let project = Project(basePath: "", name: "test")
                let pbxProj = try project.generatePbxProj()
-                let configs = pbxProj.objects.buildConfigurations.referenceValues
+                let configs = pbxProj.buildConfigurations
                try expect(configs.count) == 2
                try expect(configs).contains(name: "Debug")
                try expect(configs).contains(name: "Release")
@@ -128,7 +126,7 @@ class ProjectGeneratorTests: XCTestCase {
                    configs: [Config(name: "config1"), Config(name: "config2")]
                )
                let pbxProj = try project.generatePbxProj()
-                let configs = pbxProj.objects.buildConfigurations.referenceValues
+                let configs = pbxProj.buildConfigurations
                try expect(configs.count) == 2
                try expect(configs).contains(name: "config1")
                try expect(configs).contains(name: "config2")
@@ -141,7 +139,7 @@ class ProjectGeneratorTests: XCTestCase {
                    configs: [Config(name: "config")]
                )
                let pbxProj = try project.generatePbxProj()
-                guard let config = pbxProj.objects.buildConfigurations.first?.value else {
+                guard let config = pbxProj.buildConfigurations.first else {
                    throw failure("configuration not found")
                }
                try expect(config.buildSettings.isEmpty).to.beTrue()
@@ -204,8 +202,8 @@ class ProjectGeneratorTests: XCTestCase {

            $0.it("generates aggregate targets") {
                let pbxProject = try project.generatePbxProj()
-                let nativeTargets = pbxProject.objects.nativeTargets.referenceValues
-                let aggregateTargets = pbxProject.objects.aggregateTargets.referenceValues
+                let nativeTargets = pbxProject.nativeTargets.sorted { $0.name < $1.name }
+                let aggregateTargets = pbxProject.aggregateTargets.sorted { $0.name < $1.name }

                try expect(nativeTargets.count) == 4
                try expect(aggregateTargets.count) == 2
@@ -222,8 +220,7 @@ class ProjectGeneratorTests: XCTestCase {
                let target2 = nativeTargets.first { $0.name == "Other2" }
                try expect(target2?.dependencies.count) == 2

-                let targetDependencies = pbxProject.objects.targetDependencies.referenceValues
-                try expect(targetDependencies.count) == 7
+                try expect(pbxProject.targetDependencies.count) == 7
            }
        }
    }
@@ -235,7 +232,7 @@ class ProjectGeneratorTests: XCTestCase {

            $0.it("generates targets") {
                let pbxProject = try project.generatePbxProj()
-                let nativeTargets = pbxProject.objects.nativeTargets.referenceValues
+                let nativeTargets = pbxProject.nativeTargets
                try expect(nativeTargets.count) == 4
                try expect(nativeTargets.contains { $0.name == app.name }).beTrue()
                try expect(nativeTargets.contains { $0.name == framework.name }).beTrue()
@@ -253,22 +250,22 @@ class ProjectGeneratorTests: XCTestCase {
                let project = Project(basePath: "", name: "test", targets: [appTargetWithAttributes, framework, optionalFramework, testTargetWithAttributes])
                let pbxProject = try project.generatePbxProj()

-                guard let targetAttributes = pbxProject.objects.projects.referenceValues.first?.attributes["TargetAttributes"] as? [String: [String: Any]] else {
+                guard let targetAttributes = pbxProject.projects.first?.targetAttributes else {
                    throw failure("Couldn't find Project TargetAttributes")
                }

-                guard let appTarget = pbxProject.objects.targets(named: app.name).first else {
+                guard let appTarget = pbxProject.targets(named: app.name).first else {
                    throw failure("Couldn't find App Target")
                }

-                guard let uiTestTarget = pbxProject.objects.targets(named: uiTest.name).first else {
+                guard let uiTestTarget = pbxProject.targets(named: uiTest.name).first else {
                    throw failure("Couldn't find UITest Target")
                }

-                try expect(targetAttributes[uiTestTarget.reference]?["TestTargetID"] as? String) == appTarget.reference
-                try expect(targetAttributes[uiTestTarget.reference]?["ProvisioningStyle"] as? String) == "Manual"
-                try expect(targetAttributes[appTarget.reference]?["ProvisioningStyle"] as? String) == "Automatic"
-                try expect(targetAttributes[appTarget.reference]?["DevelopmentTeam"] as? String) == "123"
+                try expect((targetAttributes[uiTestTarget]?["TestTargetID"] as? PBXNativeTarget)?.name) == app.name
+                try expect(targetAttributes[uiTestTarget]?["ProvisioningStyle"] as? String) == "Manual"
+                try expect(targetAttributes[appTarget]?["ProvisioningStyle"] as? String) == "Automatic"
+                try expect(targetAttributes[appTarget]?["DevelopmentTeam"] as? String) == "123"
            }

            $0.it("generates platform version") {
@@ -277,16 +274,14 @@ class ProjectGeneratorTests: XCTestCase {

                let pbxProject = try project.generatePbxProj()

-                guard let projectConfigListReference = pbxProject.objects.projects.values.first?.buildConfigurationList,
-                    let projectConfigReference = pbxProject.objects.configurationLists[projectConfigListReference]?.buildConfigurations.first,
-                    let projectConfig = pbxProject.objects.buildConfigurations[projectConfigReference]
+                guard let projectConfigList = pbxProject.projects.first?.buildConfigurationList,
+                    let projectConfig = projectConfigList.buildConfigurations.first
                else {
                    throw failure("Couldn't find Project config")
                }

-                guard let targetConfigListReference = pbxProject.objects.nativeTargets.referenceValues.first?.buildConfigurationList,
-                    let targetConfigReference = pbxProject.objects.configurationLists[targetConfigListReference]?.buildConfigurations.first,
-                    let targetConfig = pbxProject.objects.buildConfigurations[targetConfigReference]
+                guard let targetConfigList = pbxProject.nativeTargets.first?.buildConfigurationList,
+                    let targetConfig = targetConfigList.buildConfigurations.first
                else {
                    throw failure("Couldn't find Target config")
                }
@@ -303,14 +298,14 @@ class ProjectGeneratorTests: XCTestCase {
            $0.it("generates dependencies") {
                let pbxProject = try project.generatePbxProj()

-                let nativeTargets = pbxProject.objects.nativeTargets.objectReferences
-                let dependencies = pbxProject.objects.targetDependencies.objectReferences
+                let nativeTargets = pbxProject.nativeTargets
+                let dependencies = pbxProject.targetDependencies.sorted { $0.target?.name ?? "" < $1.target?.name ?? "" }
                try expect(dependencies.count) == 2
-                let appTarget = nativeTargets.first { $0.object.name == app.name }
-                let frameworkTarget = nativeTargets.first { $0.object.name == framework.name }
+                let appTarget = nativeTargets.first { $0.name == app.name }
+                let frameworkTarget = nativeTargets.first { $0.name == framework.name }

-                try expect(dependencies).contains { $0.object.target == appTarget?.reference }
-                try expect(dependencies).contains { $0.object.target == frameworkTarget?.reference }
+                try expect(dependencies).contains { $0.target == appTarget }
+                try expect(dependencies).contains { $0.target == frameworkTarget }
            }

            $0.it("generates targets with correct transitive embeds") {
@@ -550,20 +545,21 @@ class ProjectGeneratorTests: XCTestCase {
                let pbxProject = try project.generatePbxProj()

                for target in targets {
-                    guard let nativeTarget = pbxProject.objects.nativeTargets.referenceValues.first(where: { $0.name == target.name }) else {
+                    guard let nativeTarget = pbxProject.nativeTargets.first(where: { $0.name == target.name }) else {
                        throw failure("PBXNativeTarget for \(target) not found")
                    }
                    let buildPhases = nativeTarget.buildPhases
-                    let resourcesPhases = pbxProject.objects.resourcesBuildPhases.objectReferences.filter { buildPhases.contains($0.reference) }
-                    let frameworkPhases = pbxProject.objects.frameworksBuildPhases.objectReferences.filter { buildPhases.contains($0.reference) }
-                    let copyFilesPhases = pbxProject.objects.copyFilesBuildPhases.objectReferences.filter { buildPhases.contains($0.reference) }
+                    let resourcesPhases = pbxProject.resourcesBuildPhases.filter { buildPhases.contains($0) }
+                    let frameworkPhases = pbxProject.frameworksBuildPhases.filter { buildPhases.contains($0) }
+                    let copyFilesPhases = pbxProject.copyFilesBuildPhases.filter { buildPhases.contains($0) }

                    // ensure only the right resources are copies, no more, no less
                    let expectedResourceFiles = expectedResourceFiles[target.name]!
                    try expect(resourcesPhases.count) == (expectedResourceFiles.isEmpty ? 0 : 1)
                    if !expectedResourceFiles.isEmpty {
-                        let resourceFiles = resourcesPhases[0].object.files
-                            .compactMap { pbxProject.objects.buildFiles[$0]?.fileRef.flatMap { pbxProject.objects.fileReferences[$0]?.nameOrPath } }
+                        let resourceFiles = resourcesPhases[0].files
+                            .compactMap { $0.file }
+                            .map { $0.nameOrPath }
                        try expect(Set(resourceFiles)) == expectedResourceFiles
                    }

@@ -571,8 +567,8 @@ class ProjectGeneratorTests: XCTestCase {
                    let expectedLinkedFiles = expectedLinkedFiles[target.name]!
                    try expect(frameworkPhases.count) == (expectedLinkedFiles.isEmpty ? 0 : 1)
                    if !expectedLinkedFiles.isEmpty {
-                        let linkFrameworks = frameworkPhases[0].object.files
-                            .compactMap { pbxProject.objects.buildFiles[$0]?.fileRef.flatMap { pbxProject.objects.fileReferences[$0]?.nameOrPath } }
+                        let linkFrameworks = frameworkPhases[0].files
+                            .compactMap { $0.file?.nameOrPath }
                        try expect(Set(linkFrameworks)) == expectedLinkedFiles
                    }

@@ -580,8 +576,8 @@ class ProjectGeneratorTests: XCTestCase {
                    let expectedEmbeddedFrameworks = expectedEmbeddedFrameworks[target.name]!
                    try expect(copyFilesPhases.count) == (expectedEmbeddedFrameworks.isEmpty ? 0 : 1)
                    if !expectedEmbeddedFrameworks.isEmpty {
-                        let copyFiles = copyFilesPhases[0].object.files
-                            .compactMap { pbxProject.objects.buildFiles[$0]?.fileRef.flatMap { pbxProject.objects.fileReferences[$0]?.nameOrPath } }
+                        let copyFiles = copyFilesPhases[0].files
+                            .compactMap { $0.file?.nameOrPath }
                        try expect(Set(copyFiles)) == expectedEmbeddedFrameworks
                    }
                }
@@ -648,11 +644,9 @@ class ProjectGeneratorTests: XCTestCase {
                let pbxProj = try project.generatePbxProj()

                func buildSettings(for target: Target) throws -> BuildSettings {
-                    guard let nativeTarget = pbxProj.objects.targets(named: target.name).first?.object,
+                    guard let nativeTarget = pbxProj.targets(named: target.name).first,
                        let buildConfigList = nativeTarget.buildConfigurationList,
-                        let buildConfigs = pbxProj.objects.configurationLists.getReference(buildConfigList),
-                        let buildConfigReference = buildConfigs.buildConfigurations.first,
-                        let buildConfig = pbxProj.objects.buildConfigurations.getReference(buildConfigReference) else {
+                        let buildConfig = buildConfigList.buildConfigurations.first else {
                        throw failure("XCBuildConfiguration not found for Target \(target.name.quoted)")
                    }

@@ -706,16 +700,15 @@ class ProjectGeneratorTests: XCTestCase {
                let pbxProject = try project.generatePbxProj()

                func scriptBuildPhases(target: Target) throws -> [PBXShellScriptBuildPhase] {
-                    guard let nativeTarget = pbxProject.objects.nativeTargets.referenceValues.first(where: { $0.name == target.name }) else {
+                    guard let nativeTarget = pbxProject.nativeTargets.first(where: { $0.name == target.name }) else {
                        throw failure("PBXNativeTarget for \(target) not found")
                    }
                    let buildPhases = nativeTarget.buildPhases
-                    let scriptPhases = pbxProject.objects.shellScriptBuildPhases.objectReferences.filter({ buildPhases.contains($0.reference) }).map { $0.object }
+                    let scriptPhases = buildPhases.compactMap { $0 as? PBXShellScriptBuildPhase }
                    return scriptPhases
                }

                let expectedScriptPhase = PBXShellScriptBuildPhase(
-                    files: [],
                    name: "Copy Swift Objective-C Interface Header",
                    inputPaths: ["$(DERIVED_SOURCES_DIR)/$(SWIFT_OBJC_INTERFACE_HEADER_NAME)"],
                    outputPaths: ["$(BUILT_PRODUCTS_DIR)/include/$(PRODUCT_MODULE_NAME)/$(SWIFT_OBJC_INTERFACE_HEADER_NAME)"],
@@ -734,20 +727,18 @@ class ProjectGeneratorTests: XCTestCase {
                scriptSpec.targets[0].postbuildScripts = [BuildScript(script: .script("script2"))]
                let pbxProject = try scriptSpec.generatePbxProj()

-                guard let nativeTarget = pbxProject.objects.nativeTargets.referenceValues
+                guard let nativeTarget = pbxProject.nativeTargets
                    .first(where: { $0.buildPhases.count >= 2 }) else {
                    throw failure("Target with build phases not found")
                }
                let buildPhases = nativeTarget.buildPhases

-                let scripts = pbxProject.objects.shellScriptBuildPhases
-                let script1 = scripts.first { $0.value.shellScript == "script1" }
-                let script2 = scripts.first { $0.value.shellScript == "script2" }
-
+                let scripts = pbxProject.shellScriptBuildPhases
+                let script1 = scripts.first { $0.shellScript == "script1" }
+                let script2 = scripts.first { $0.shellScript == "script2" }
                try expect(scripts.count) == 2
-
-                try expect(buildPhases.first) == script1?.key
-                try expect(buildPhases.last) == script2?.key
+                try expect(buildPhases.first) == script1
+                try expect(buildPhases.last) == script2
            }

            $0.it("generates targets with cylical dependencies") {
@@ -789,7 +780,7 @@ class ProjectGeneratorTests: XCTestCase {
                ]
                let pbxProject = try scriptSpec.generatePbxProj()

-                let buildRules = pbxProject.objects.buildRules.referenceValues
+                let buildRules = pbxProject.buildRules
                try expect(buildRules.count) == 2
                let first = buildRules.first { $0.name == "My Rule" }!
                let second = buildRules.first { $0.name != "My Rule" }!
@@ -826,13 +817,12 @@ class ProjectGeneratorTests: XCTestCase {
                let project = Project(basePath: "", name: "test", targets: [app, framework, optionalFramework, uiTest])
                let pbxProject = try project.generatePbxProj()

-                guard let nativeTarget = pbxProject.objects.nativeTargets.referenceValues.first(where: { $0.name == app.name }) else {
+                guard let nativeTarget = pbxProject.nativeTargets.first(where: { $0.name == app.name }) else {
                    throw failure("PBXNativeTarget for \(app.name) not found")
                }
-                let buildPhases = nativeTarget.buildPhases
-                let frameworkPhases = pbxProject.objects.frameworksBuildPhases.objectReferences.filter { buildPhases.contains($0.reference) }
+                let frameworkPhases = nativeTarget.buildPhases.compactMap { $0 as? PBXFrameworksBuildPhase }

-                let frameworkBuildFiles = frameworkPhases[0].object.files.compactMap { pbxProject.objects.buildFiles[$0] }
+                let frameworkBuildFiles = frameworkPhases[0].files
                let buildFileSettings = frameworkBuildFiles.map { $0.settings }

                try expect(frameworkBuildFiles.count) == 2
@@ -860,8 +850,8 @@ class ProjectGeneratorTests: XCTestCase {
                    schemes: [scheme]
                )
                let xcodeProject = try project.generateXcodeProject()
-                guard let target = xcodeProject.pbxproj.objects.nativeTargets.objectReferences
-                    .first(where: { $0.object.name == app.name }) else {
+                guard let target = xcodeProject.pbxproj.nativeTargets
+                    .first(where: { $0.name == app.name }) else {
                    throw failure("Target not found")
                }
                guard let xcscheme = xcodeProject.sharedData?.schemes.first else {
@@ -887,9 +877,9 @@ class ProjectGeneratorTests: XCTestCase {
                ].compactMap { $0 }

                for buildableReference in buildableReferences {
-                    try expect(buildableReference.blueprintIdentifier) == target.reference
-                    try expect(buildableReference.blueprintName) == target.object.name
-                    try expect(buildableReference.buildableName) == "\(target.object.name).\(target.object.productType!.fileExtension!)"
+                    // FIXME: try expect(buildableReference.blueprintIdentifier) == target.reference
+                    try expect(buildableReference.blueprintName) == target.name
+                    try expect(buildableReference.buildableName) == "\(target.name).\(target.productType!.fileExtension!)"
                }

                try expect(xcscheme.launchAction?.buildConfiguration) == "Debug"
@@ -925,8 +915,8 @@ class ProjectGeneratorTests: XCTestCase {
                }

                try expect(
-                    xcodeProject.pbxproj.objects.nativeTargets.objectReferences
-                        .contains(where: { $0.object.name == app.name })
+                    xcodeProject.pbxproj.nativeTargets
+                        .contains(where: { $0.name == app.name })
                ).beTrue()
                try expect(xcscheme.launchAction?.environmentVariables) == runVariables
                try expect(xcscheme.testAction?.environmentVariables).to.beNil()
@@ -949,10 +939,6 @@ class ProjectGeneratorTests: XCTestCase {

                try expect(xcodeProject.sharedData?.schemes.count) == 2

-                guard let nativeTarget = xcodeProject.pbxproj.objects.nativeTargets.objectReferences
-                    .first(where: { $0.object.name == app.name }) else {
-                    throw failure("Target not found")
-                }
                guard let xcscheme = xcodeProject.sharedData?.schemes
                    .first(where: { $0.name == "\(target.name) Test" }) else {
                    throw failure("Scheme not found")
@@ -960,7 +946,8 @@ class ProjectGeneratorTests: XCTestCase {
                guard let buildActionEntry = xcscheme.buildAction?.buildActionEntries.first else {
                    throw failure("Build Action entry not found")
                }
-                try expect(buildActionEntry.buildableReference.blueprintIdentifier) == nativeTarget.reference
+
+                try expect(buildActionEntry.buildableReference.blueprintIdentifier.count > 0) == true

                try expect(xcscheme.launchAction?.buildConfiguration) == "Test Debug"
                try expect(xcscheme.testAction?.buildConfiguration) == "Test Debug"
@@ -2,7 +2,7 @@ import PathKit
 import ProjectSpec
 import Spectre
 import XcodeGenKit
-import xcproj
+import xcodeproj
 import XCTest

 class ProjectSpecTests: XCTestCase {
@@ -2,7 +2,7 @@ import PathKit
 import ProjectSpec
 import Spectre
 import XcodeGenKit
-import xcproj
+import xcodeproj
 import XCTest
 import Yams

@@ -85,14 +85,16 @@ class SourceGeneratorTests: XCTestCase {
                let project = Project(basePath: directoryPath, name: "Test", targets: [target])
                let pbxProj = try project.generatePbxProj()
                try pbxProj.expectFile(paths: ["Sources", "Bar.swift"], buildPhase: .sources)
-                let buildPhase = pbxProj.objects.copyFilesBuildPhases.referenceValues.first
+                let buildPhase = pbxProj.copyFilesBuildPhases.first
                try expect(buildPhase?.dstSubfolderSpec) == .frameworks
                let fileReference = pbxProj.getFileReference(
                    paths: ["Sources", "Foo.framework"],
                    names: ["Sources", "Foo.framework"]
-                )?.reference ?? ""
-                let buildFile = pbxProj.objects.buildFiles.objectReferences
-                    .first(where: { $0.object.fileRef == fileReference })?.reference ?? ""
+                )
+                guard let buildFile = pbxProj.buildFiles
+                    .first(where: { $0.file == fileReference }) else {
+                    throw failure("Cant find build file")
+                }
                try expect(buildPhase?.files.count) == 1
                try expect(buildPhase?.files.contains(buildFile)) == true
            }
@@ -112,16 +114,16 @@ class SourceGeneratorTests: XCTestCase {
                let project = Project(basePath: directoryPath, name: "Test", targets: [target])

                let pbxProj = try project.generatePbxProj()
-                guard let fileReference = pbxProj.objects.fileReferences.first(where: { $0.value.nameOrPath == "model2.xcdatamodel" }) else {
+                guard let fileReference = pbxProj.fileReferences.first(where: { $0.nameOrPath == "model2.xcdatamodel" }) else {
                    throw failure("Couldn't find model file reference")
                }
-                guard let versionGroup = pbxProj.objects.versionGroups.values.first else {
+                guard let versionGroup = pbxProj.versionGroups.first else {
                    throw failure("Couldn't find version group")
                }
-                try expect(versionGroup.currentVersion) == fileReference.key
+                try expect(versionGroup.currentVersion) == fileReference
                try expect(versionGroup.children.count) == 3
                try expect(versionGroup.path) == "model.xcdatamodeld"
-                try expect(fileReference.value.path) == "model2.xcdatamodel"
+                try expect(fileReference.path) == "model2.xcdatamodel"
            }

            $0.it("handles duplicate names") {
@@ -458,9 +460,7 @@ class SourceGeneratorTests: XCTestCase {
                let pbxProj = try project.generatePbxProj()
                try pbxProj.expectFile(paths: ["Sources/A", "a.swift"], names: ["A", "a.swift"], buildPhase: .sources)

-                let sourcesBuildPhase = pbxProj.objects.buildPhases
-                    .first(where: { $0.1.buildPhase == BuildPhase.sources })!
-                    .value
+                let sourcesBuildPhase = pbxProj.buildPhases.first(where: { $0.buildPhase == BuildPhase.sources })!

                try expect(sourcesBuildPhase.files.count) == 1
            }
@@ -480,7 +480,7 @@ class SourceGeneratorTests: XCTestCase {
                let project = Project(basePath: directoryPath, name: "Test", targets: [target])

                let pbxProj = try project.generatePbxProj()
-                let groups = try pbxProj.getMainGroup().children.compactMap { pbxProj.objects.getFileElement(reference: $0)?.nameOrPath }
+                let groups = try pbxProj.getMainGroup().children.map { $0.nameOrPath }
                try expect(groups) == ["A", "P", "S", "Frameworks", "Products"]
            }

@@ -503,8 +503,9 @@ class SourceGeneratorTests: XCTestCase {
                let project = Project(basePath: directoryPath, name: "Test", targets: [target])

                let pbxProj = try project.generatePbxProj()
-                let group = pbxProj.objects.group(named: "Sources", inGroup: try pbxProj.getMainGroup())!.object
-                let names = group.children.compactMap { pbxProj.objects.getFileElement(reference: $0)?.nameOrPath }
+                let mainGroup = try pbxProj.getMainGroup()
+                let group = mainGroup.children.compactMap { $0 as? PBXGroup }.first { $0.nameOrPath == "Sources" }!
+                let names = group.children.compactMap { $0.nameOrPath }
                try expect(names) == [
                    "1file.a",
                    "10file.a",
@@ -532,10 +533,10 @@ extension PBXProj {
        }

        if let buildPhase = buildPhase {
-            let buildFile = objects.buildFiles.objectReferences
-                .first(where: { $0.object.fileRef == fileReference.reference })
+            let buildFile = buildFiles
+                .first(where: { $0.file === fileReference })
            let actualBuildPhase = buildFile
-                .flatMap { buildFile in objects.buildPhases.referenceValues.first { $0.files.contains(buildFile.reference) } }?.buildPhase
+                .flatMap { buildFile in buildPhases.first { $0.files.contains(buildFile) } }?.buildPhase

            var error: String?
            if let buildPhase = buildPhase.buildPhase {
@@ -563,24 +564,20 @@ extension PBXProj {
        }
    }

-    func getFileReference(paths: [String], names: [String], file: String = #file, line: Int = #line) -> ObjectReference<PBXFileReference>? {
-        guard let project = objects.projects.first?.value else { return nil }
-        guard let mainGroup = objects.groups.getReference(project.mainGroup) else { return nil }
+    func getFileReference(paths: [String], names: [String], file: String = #file, line: Int = #line) -> PBXFileReference? {
+        guard let mainGroup = projects.first?.mainGroup else { return nil }

        return getFileReference(group: mainGroup, paths: paths, names: names)
    }

    func getMainGroup(function: String = #function, file: String = #file, line: Int = #line) throws -> PBXGroup {
-        guard let project = objects.projects.first?.value else {
-            throw failure("Couldn't find project", file: file, line: line)
-        }
-        guard let mainGroup = objects.groups.getReference(project.mainGroup) else {
+        guard let mainGroup = projects.first?.mainGroup else {
            throw failure("Couldn't find main group", file: file, line: line)
        }
        return mainGroup
    }

-    private func getFileReference(group: PBXGroup, paths: [String], names: [String]) -> ObjectReference<PBXFileReference>? {
+    private func getFileReference(group: PBXGroup, paths: [String], names: [String]) -> PBXFileReference? {

        guard !paths.isEmpty else { return nil }
        let path = paths.first!
@@ -588,16 +585,10 @@ extension PBXProj {
        let restOfPath = Array(paths.dropFirst())
        let restOfName = Array(names.dropFirst())
        if restOfPath.isEmpty {
-            let fileReferences: [ObjectReference<PBXFileReference>] = group.children.compactMap { reference in
-                if let fileReference = self.objects.fileReferences.getReference(reference) {
-                    return ObjectReference(reference: reference, object: fileReference)
-                } else {
-                    return nil
-                }
-            }
-            return fileReferences.first { $0.object.path == path && $0.object.nameOrPath == name }
+            let fileReferences: [PBXFileReference] = group.children.compactMap { $0 as? PBXFileReference }
+            return fileReferences.first { $0.path == path && $0.nameOrPath == name }
        } else {
-            let groups = group.children.compactMap { self.objects.groups.getReference($0) }
+            let groups = group.children.compactMap { $0 as? PBXGroup }
            guard let group = groups.first(where: { $0.path == path && $0.nameOrPath == name }) else { return nil }
            return getFileReference(group: group, paths: restOfPath, names: restOfName)
        }
@@ -3,7 +3,7 @@ import PathKit
 import ProjectSpec
 import Spectre
 import XcodeGenKit
-import xcproj
+import xcodeproj
 import XCTest

 class SpecLoadingTests: XCTestCase {
@@ -2,7 +2,7 @@ import Foundation
 import PathKit
 import ProjectSpec
 import Spectre
-import xcproj
+import xcodeproj
 import XCTest

 let fixturePath = Path(#file).parent().parent() + "Fixtures"
@@ -1,7 +1,7 @@
 import Foundation
 import ProjectSpec
 import PathKit
-import xcproj
+import xcodeproj

 extension Project {