Parallelize get, install & update

Sources/mas/Commands/MAS.Get.swift

@@ -20,9 +20,15 @@ extension MAS {
 		private var forceOptionGroup: ForceOptionGroup
 		@OptionGroup
 		private var catalogAppsOptionGroup: CatalogAppsOptionGroup
+		@OptionGroup
+		private var jobsOptionGroup: JobsOptionGroup
 
 		func run() async {
-			await AppStore.get.apps(withAppIDs: catalogAppsOptionGroup.appIDs, force: forceOptionGroup.force)
+			await AppStore.get.apps(
+				withAppIDs: catalogAppsOptionGroup.appIDs,
+				force: forceOptionGroup.force,
+				maxConcurrentTaskCount: jobsOptionGroup.jobs,
+			)
 		}
 	}
 }

Sources/mas/Commands/MAS.Install.swift

@@ -19,9 +19,15 @@ extension MAS {
 		private var forceOptionGroup: ForceOptionGroup
 		@OptionGroup
 		private var catalogAppsOptionGroup: CatalogAppsOptionGroup
+		@OptionGroup
+		private var jobsOptionGroup: JobsOptionGroup
 
 		func run() async {
-			await AppStore.install.apps(withAppIDs: catalogAppsOptionGroup.appIDs, force: forceOptionGroup.force)
+			await AppStore.install.apps(
+				withAppIDs: catalogAppsOptionGroup.appIDs,
+				force: forceOptionGroup.force,
+				maxConcurrentTaskCount: jobsOptionGroup.jobs,
+			)
 		}
 	}
 }

Sources/mas/Commands/MAS.Lucky.swift

@@ -32,7 +32,7 @@ extension MAS {
 				throw MASError.noCatalogAppsFound(for: searchTerm)
 			}
 
-			await AppStore.install.apps(withADAMIDs: [adamID], force: forceOptionGroup.force)
+			await AppStore.install.apps(withADAMIDs: [adamID], force: forceOptionGroup.force, maxConcurrentTaskCount: 1)
 		}
 	}
 }

Sources/mas/Commands/MAS.Update.swift

@@ -20,12 +20,15 @@ extension MAS {
 		private var forceOptionGroup: ForceOptionGroup
 		@OptionGroup
 		private var outdatedAppsOptionGroup: OutdatedAppsOptionGroup
+		@OptionGroup
+		private var jobsOptionGroup: JobsOptionGroup
 
 		func run() async {
 			await AppStore.update.apps(
 				withADAMIDs: await outdatedAppsOptionGroup
 					.outdatedApps(considerAllOutdated: forceOptionGroup.force, withFullJSON: false)
 					.map(\.installedApp.adamID),
+				maxConcurrentTaskCount: jobsOptionGroup.jobs,
 			)
 		}
 	}

Sources/mas/Commands/OptionGroups/JobsOptionGroup.swift

@@ -0,0 +1,19 @@
+//
+// JobsOptionGroup.swift
+// mas
+//
+// Copyright © 2026 mas-cli. All rights reserved.
+//
+
+internal import ArgumentParser
+
+struct JobsOptionGroup: ParsableArguments {
+	@Option(name: [.customShort("j"), .long], help: "Maximum number of apps to download & install concurrently")
+	private(set) var jobs = 4
+
+	func validate() throws(ValidationError) {
+		if jobs < 1 {
+			throw .init("--jobs must be at least 1")
+		}
+	}
+}

Sources/mas/Commands/OptionGroups/OutdatedAppsOptionGroup.swift

@@ -70,12 +70,16 @@ struct OutdatedAppsOptionGroup: ParsableArguments {
 
 					let newVersionGate = OSAllocatedUnfairLock(initialState: String?.none)
 					do {
-						try await AppStore.install.app(withADAMID: installedApp.adamID) { appStoreVersion, shouldOutput in
-							if shouldOutput, let appStoreVersion, installedApp.version != appStoreVersion {
-								newVersionGate.withLock { $0 = appStoreVersion }
-							}
-							return true
-						}
+						try await AppStore.install.app(
+							withADAMID: installedApp.adamID,
+							shouldCancel: { appStoreVersion, shouldOutput in
+								if shouldOutput, let appStoreVersion, installedApp.version != appStoreVersion {
+									newVersionGate.withLock { $0 = appStoreVersion }
+								}
+								return true
+							},
+							board: ProgressBoard(),
+						)
 					} catch is CancellationError {
 						// Fallthrough
 					} catch {

Sources/mas/Models/AppStoreAction.swift

@@ -42,11 +42,15 @@ enum AppStoreAction: String {
 		}
 	}
 
-	func apps(withAppIDs appIDs: [AppID], force: Bool) async {
-		await apps(withADAMIDs: await appIDs.catalogApps.map(\.adamID), force: force)
+	func apps(withAppIDs appIDs: [AppID], force: Bool, maxConcurrentTaskCount: Int) async {
+		await apps(
+			withADAMIDs: await appIDs.catalogApps.map(\.adamID),
+			force: force,
+			maxConcurrentTaskCount: maxConcurrentTaskCount,
+		)
 	}
 
-	func apps(withADAMIDs adamIDs: [ADAMID], force: Bool) async {
+	func apps(withADAMIDs adamIDs: [ADAMID], force: Bool, maxConcurrentTaskCount: Int) async {
 		let installedAppByADAMID = await installedApps(withAppIDs: adamIDs.map(AppID.adamID), withFullJSON: false) { _ in }
 			.reduce(into: [ADAMID: InstalledApp]()) { $0[$1.adamID] = $1 }
 		await apps(
@@ -60,19 +64,41 @@ enum AppStoreAction: String {
 					MAS.printer.warning("Already ", performed, " ", installedApp.name, " (", adamID, ")", separator: "")
 					return false
 				},
+			maxConcurrentTaskCount: maxConcurrentTaskCount,
 		)
 	}
 
-	func apps(withADAMIDs adamIDs: [ADAMID]) async {
+	func apps(withADAMIDs adamIDs: [ADAMID], maxConcurrentTaskCount: Int) async {
 		guard !adamIDs.isEmpty else {
 			return
 		}
 
+		let board = ProgressBoard()
 		await OrderedSet(adamIDs)
-			.forEach(attemptTo: "\(self) app for ADAM ID") { try await app(withADAMID: $0) { _, _ in false } }
+			.concurrentForEach(attemptTo: "\(self) app for ADAM ID", maxConcurrentTaskCount: maxConcurrentTaskCount) {
+				try await app(withADAMID: $0, shouldCancel: { _, _ in false }, board: board)
+			}
+	}
+
+	func app(
+		withADAMID adamID: ADAMID,
+		shouldCancel: @escaping @Sendable (String?, Bool) -> Bool,
+		board: ProgressBoard,
+	) async throws {
+		await board.update(adamID: adamID, row: "\(adamID) \(performing.uppercasingFirst)")
+		do {
+			try await performApp(withADAMID: adamID, shouldCancel: shouldCancel, board: board)
+		} catch {
+			await board.finish(adamID: adamID)
+			throw error
+		}
 	}
 
-	func app(withADAMID adamID: ADAMID, shouldCancel: @escaping @Sendable (String?, Bool) -> Bool) async throws {
+	private func performApp(
+		withADAMID adamID: ADAMID,
+		shouldCancel: @escaping @Sendable (String?, Bool) -> Bool,
+		board: ProgressBoard,
+	) async throws {
 		let (eventStream, eventContinuation) = AsyncStream.makeStream(of: QueueEvent.self)
 		let observerUUID = await DownloadQueueObserver(
 			action: self,
@@ -161,6 +187,7 @@ enum AppStoreAction: String {
 						error: error,
 					)
 				}
+				var permanentLines = [String]()
 				switch snapshot.activePhaseType {
 				case prevPhaseType:
 					break
@@ -169,53 +196,48 @@ enum AppStoreAction: String {
 					.downloaded where prevPhaseType == .downloading,
 					.performing
 				: // swiftformat:disable:this indent
-					MAS.printer.clearCurrentLine(of: .standardOutput)
-					MAS.printer.notice(snapshot.activePhaseType, snapshot.appNameAndVersion)
+					permanentLines.append("\(snapshot.activePhaseType) \(snapshot.appNameAndVersion)")
 				default:
 					break
 				}
-				if
-					FileHandle.standardOutput.isTerminal,
-					snapshot.phasePercentComplete != 0 || snapshot.activePhaseType != .processing
-				{
-					// Output the progress bar iff connected to a terminal
+				var row = String?.none
+				if snapshot.phasePercentComplete != 0 || snapshot.activePhaseType != .processing {
 					let totalLength = 60
 					let completedLength = Int(snapshot.phasePercentComplete * .init(totalLength))
-					MAS.printer.clearCurrentLine(of: .standardOutput)
-					MAS.printer.info(
-						String(repeating: "#", count: completedLength),
-						String(repeating: "-", count: totalLength - completedLength),
-						" ",
-						UInt64((snapshot.phasePercentComplete * 100).rounded()),
-						"% ",
-						snapshot.activePhaseType.performed,
-						separator: "",
-						terminator: "",
-					)
+					row = """
+						\(snapshot.appNameAndVersion) \
+						\(String(repeating: "#", count: completedLength))\(String(repeating: "-", count: totalLength - completedLength)) \
+						\(UInt64((snapshot.phasePercentComplete * 100).rounded()))% \(snapshot.activePhaseType.performed)
+						"""
 				}
+				await board.update(adamID: adamID, permanentLines: permanentLines, row: row)
 				prevPhaseType = snapshot.activePhaseType
 			case let .removed(snapshot):
-				MAS.printer.clearCurrentLine(of: .standardOutput)
 				let appFolderURL: URL?
 				if let error = snapshot.error {
 					guard error is Ignorable else {
 						throw error
 					}
 
-					MAS.printer.notice(PhaseType.downloaded, snapshot.appNameAndVersion)
-					MAS.printer.notice(performing.uppercasingFirst, snapshot.appNameAndVersion)
-					MAS.printer.info(rawValue.uppercasingFirst, "progress cannot be displayed", terminator: "")
+					await board.update(
+						adamID: adamID,
+						permanentLines: [
+							"\(PhaseType.downloaded) \(snapshot.appNameAndVersion)",
+							"\(performing.uppercasingFirst) \(snapshot.appNameAndVersion)",
+						],
+						row: "\(snapshot.appNameAndVersion) \(rawValue.uppercasingFirst) progress cannot be displayed",
+					)
 					appFolderURL = try await install(
 						appNameAndVersion: snapshot.appNameAndVersion,
 						pkgHardLinkURL: pkgHardLinkURL,
 						receiptHardLinkURL: receiptHardLinkURL,
 					)
-					MAS.printer.clearCurrentLine(of: .standardOutput)
 				} else {
 					guard !snapshot.isFailed else {
 						throw MASError.error("Failed to download \(snapshot.appNameAndVersion)")
 					}
 					guard !shouldCancel(snapshot.version, false) else {
+						await board.finish(adamID: adamID)
 						return
 					}
 					guard !snapshot.isCancelled else {
@@ -225,9 +247,13 @@ enum AppStoreAction: String {
 					appFolderURL = snapshot.appFolderPath.map { .init(folderPath: $0) }
 				}
 
-				MAS.printer.notice(
-					[performed.uppercasingFirst, snapshot.appNameAndVersion]
-						+ (appFolderURL.map { ["in", $0.filePath] } ?? .init()),
+				await board.finish(
+					adamID: adamID,
+					permanentLines: [
+						([performed.uppercasingFirst, snapshot.appNameAndVersion]
+							+ (appFolderURL.map { ["in", $0.filePath] } ?? .init()))
+							.joined(separator: " "),
+					],
 				)
 
 				if let appFolderURL {

Sources/mas/Utilities/Output/Printer.swift

@@ -8,6 +8,7 @@
 private import ArgumentParser
 private import Atomics
 internal import Foundation
+private import OrderedCollections
 
 /// Prints to `FileHandle`s like `.standardOutput` & `.standardError` with ANSI
 /// color codes when connected to a terminal.
@@ -83,12 +84,6 @@ struct Printer {
 		problem(items, prefix: errorPrefix, format: errorFormat, error: error, separator: separator, terminator: terminator)
 	}
 
-	func clearCurrentLine(of fileHandle: FileHandle) {
-		if fileHandle.isTerminal {
-			try? fileHandle.write(contentsOf: clearLineData)
-		}
-	}
-
 	private func problem(
 		_ items: [Any],
 		prefix: String,
@@ -160,6 +155,54 @@ extension String {
 	}
 }
 
+/// Tracks live progress lines for concurrently running operations, each
+/// identified by an `ADAMID`, redrawing all of them in place as a block at the
+/// bottom of the terminal; permanent lines interleaved with an update are
+/// printed above that block so they stay in the scrollback.
+///
+/// When `stdout` isn't a terminal, the live block is skipped entirely &
+/// permanent lines are printed as they arrive.
+actor ProgressBoard {
+	private var rows = OrderedDictionary<ADAMID, String>()
+	private var lineCount = 0
+
+	func update(adamID: ADAMID, permanentLines: [String] = [], row: String? = nil) {
+		rows[adamID] = row ?? rows[adamID] ?? ""
+		redraw(permanentLines: permanentLines)
+	}
+
+	func finish(adamID: ADAMID, permanentLines: [String] = []) {
+		rows.removeValue(forKey: adamID)
+		redraw(permanentLines: permanentLines)
+	}
+
+	private func redraw(permanentLines: [String]) {
+		guard FileHandle.standardOutput.isTerminal else {
+			for line in permanentLines {
+				MAS.printer.notice(line)
+			}
+			return
+		}
+
+		if lineCount > 0 {
+			try? FileHandle.standardOutput.write(contentsOf: moveUpData(lineCount))
+		}
+		for line in permanentLines {
+			try? FileHandle.standardOutput.write(contentsOf: clearLineData)
+			MAS.printer.notice(line)
+		}
+		for row in rows.values {
+			try? FileHandle.standardOutput.write(contentsOf: clearLineData)
+			MAS.printer.info(row)
+		}
+		lineCount = rows.count
+	}
+}
+
+private func moveUpData(_ lineCount: Int) -> Data {
+	Data("\(csi)\(lineCount)A".utf8)
+}
+
 private func indent(_ item: Any, with indent: String) -> String {
 	.init(describing: item).replacing(nonEmptyLineStartRegex, with: indent)
 }

Sources/mas/Utilities/Swift/Collection.swift

@@ -49,6 +49,18 @@ extension Collection where Element: Sendable {
 		}
 	}
 
+	/// Runs `body` concurrently for each element, letting elements that can
+	/// succeed finish even if others fail.
+	func concurrentForEach(
+		attemptTo perform: String,
+		maxConcurrentTaskCount: Int = defaultMaxConcurrentTaskCount,
+		_ body: @escaping @Sendable (Element) async throws -> Void,
+	) async {
+		_ = await concurrentCompactMap(attemptingTo: perform, maxConcurrentTaskCount: maxConcurrentTaskCount) {
+			try await body($0) as Void?
+		}
+	}
+
 	private func concurrentTransform<T: Sendable>(
 		maxConcurrentTaskCount: Int,
 		_ transform: @escaping @Sendable (Element) async throws -> T,