Scipio

Carthago delenda est

Scipio proposes a new workflow to integrate dependencies into your applications.

This product is highly inspired by Carthage and swift-create-xcframework.

Abstract

SwiftPM is the best way to integrate dependencies into your app. However, build artifacts built by Xcode are difficult to cache.

On the other hand, XCFramework is a good way to keep binaries portable.

Scipio provides a new hybrid way to manage dependencies.

First, use SwiftPM to resolve dependencies and checkout repositories. After that, this tool converts each dependency into XCFramework.

Usage

See Scipio Official Documentation for detail.

Prepare all dependencies for your application

The concept of Scipio, all dependencies wanted to be used in your application should be defined in one Package manifest.

prepare command is to build all dependencies as XCFrameworks in the manifest.

This mode is called prepare mode. See Prepare All Dependencies for Your Application for detail.

Define Package.swift to describe your application's dependencies

// swift-tools-version: 5.6
// The swift-tools-version declares the minimum version of Swift required to build this package.

import PackageDescription

let package = Package(
    name: "MyAppDependencies",
    platforms: [
        // Specify platforms to build
        .iOS(.v14),
    ],
    products: [],
    dependencies: [
        // Add dependencies
        .package(url: "https://github.com/onevcat/APNGKit.git", exact: "2.2.1"),
    ],
    targets: [
        .target(
            name: "MyAppDependency",
            dependencies: [
                // List all dependencies to build
                .product(name: "APNGKit", package: "APNGKit"),
            ]),
    ]
)

Run prepare command

$ scipio prepare path/to/MyAppDependencies
> 🔁 Resolving Dependencies...
> 🗑️ Cleaning MyAppDependencies...
> 📦 Building APNGKit for iOS
> 🚀 Combining into XCFramework...
> 📦 Building Delegate for iOS
> 🚀 Combining into XCFramework...
> ❇️ Succeeded.

All XCFrameworks are generated into MyAppDependencies/XCFramework by default.

Library Evolution support

Scipio disables to support Library Evolution feature by default.

It means built frameworks can be used only from products built with the same Swift version.

The primary reason why is Library Evolution limitation. In fact, some packages can't build with enabling Library Evolution. (https://developer.apple.com/forums/thread/123253, https://github.com/apple/swift-collections/issues/94, https://github.com/apple/swift-nio/issues/1257)

If you want to distribute generated XCFrameworks, it's recommended to enable Library Evolution. Pass --enable-library-evolution flag if you need. However, it means some packages can't be built.

Build Cache System

By default, Scipio checks whether re-building is required or not for existing XCFrameworks.

$ swift run scipio prepare --cache-policy project path/to/MyAppDependencies
> 🔁 Resolving Dependencies...
> 🗑️ Cleaning MyAppDependency...
> ✅ Valid APNGKit.xcframework is exists. Skip building.
> ✅ Valid Delegate.xcframework is exists. Skip building.
> ❇️ Succeeded.

Scipio supports Project/Local Disk/Remote Disk cache backends.

Using a remote cache, share built XCFrameworks among developers.

See Learn the Cache System for details.

Create XCFramework from a single Swift Package

Scipio also can generate XCFrameworks from a specific Swift Package. This feature is similar to swift-create-xcframework.

$ scipio create path/to/MyPackage
> 🔁 Resolving Dependencies...
> 🗑️ Cleaning MyPackage...
> 📦 Building MyPackage for iOS
> 🚀 Combining into XCFramework...
> ❇️ Succeeded.

See Convert Single Swift Package to XCFramework for detail.

Supported Xcode and Swift version

Currently, we support Swift 5.8, 5.9, and 5.10.

Swift 5.8 support will be dropped in the future.

	Xcode	Swift
✅	15.3	5.10
✅	15.0<=15.2	5.9
✅	14.3	5.8

Reliability

Scipio only builts with standard dependencies and Apple official tools to keep reliability.

How to resolve dependencies

Just run swift package resolve.

How to parse package manifests and generate Xcode projects

Scipio depends on swift-package-manager as a library.

Parsing package manifests and generating Xcode project is provided from the package. So it will be maintained in the future.

How to build XCFrameworks

Scipio only uses xcodebuild to build Frameworks and XCFrameworks.

Why Scipio

Scipio names after a historical story about Carthage.