Package.swift

// swift-tools-version: 5.6
import PackageDescription

let package = Package(
    name: "SwiftLintPlugin",
    products: [
        .plugin(name: "SwiftLintCLIPlugin", targets: ["SwiftLintCLIPlugin"])
    ],
    targets: [
        .binaryTarget(
            name: "SwiftLintBinary",
            url: "https://github.com/realm/SwiftLint/releases/download/<VERSION>/SwiftLintBinary-macos.artifactbundle.zip",
            checksum: "<CHECKSUM>"
        ),
        .plugin(
            name: "SwiftLintCLIPlugin",
            capability: .command(intent: .custom(verb: "lint", description: "Lint Swift Code")),
            dependencies: ["SwiftLintBinary"]
        )
    ]
)

SwiftLintCLIPlugin.swift

//
//  SwiftLintCLIPlugin.swift
import Foundation
import PackagePlugin

@main
struct SwiftLintCLIPlugin: CommandPlugin {
    func performCommand(context: PluginContext, arguments: [String]) async throws {
        let process = Process()
        process.launchPath = try context.tool(named: "swiftlint").path.string
        process.arguments = [
            "lint",
            "--no-cache",
            "--config",
            arguments.first! + "/.swiftlint.yml",
            arguments.first!
        ]

        try process.run()
        process.waitUntilExit()

        switch process.terminationStatus {
        case EXIT_SUCCESS:
            print("Lint the source code in \(arguments.first!).")
        default:
            let problem = "\(process.terminationReason):\(process.terminationStatus)"
            Diagnostics.error("SwiftLint invocation failed: \(problem)")
        }
    }
}