Note: MacGet is not affiliated with or endorsed by Tonec Inc. or Internet Download Manager. It's an independent free alternative.
Why another download manager?
Most "multi-threaded" download managers naively open as many TCP connections as you let them. Modern CDNs treat that as leech behavior — they TCP-RST connections after a few bytes, throttle your IP, or 403 your requests. The result: more threads = slower downloads, sometimes failures.
MacGet's engine discovers each host's true capacity at runtime and adapts:
- Adaptive demotion. When ≥4 chunk attempts fail without progress in a 10-second window (i.e., the host is rejecting parallelism), the engine halves its worker count, cancels the lowest-progress chunks, and continues. Repeats until stable.
- Per-host parallelism memory. The learned cap is persisted to
~/Library/Application Support/Macget/host_caps.json. Future downloads from that host start at the right level — no rediscovery cost.
- Stagger on spawn. Workers spawn 100 ms apart so anti-abuse middleboxes see a steady stream rather than a SYN burst from one IP.
- App Nap defense. A
ProcessInfo activity is held while any download is running, so macOS doesn't throttle CPU/network when you switch apps or minimize the window.
- Smart retry classification. Permanent failures (401/403/404/410/451, range refusals, malformed responses) fail fast. Transient errors (-1005 mid-stream RSTs, -1017 server-side stream kills, 5xx) retry with exponential backoff inside a hard global cap.
Features
- Up to 16 parallel HTTP-Range chunks per file (industry-standard cap; aria2 uses the same).
- Pause / resume / cancel with state that survives app restarts.
- Persistent queue — close the app, reopen, in-flight downloads continue.
- Drag-and-drop, clipboard watch, NSServices — paste a URL or drop a file from anywhere.
- Live thread adjustment while a download is running (subject to host caps).
- Built-in book catalogs — browse and search Project Gutenberg and the Internet Archive from inside the app, then send a book straight to the queue. Add any OPDS feed too, including your own Calibre server.
- BitTorrent — magnet links and
.torrent files download in the same queue as everything else, several at once. Off by default; seeding is bounded by a ratio and time limit you control. MacGet doesn't search for or index torrents.
- Auto-updates via Sparkle — enabled and signature-verified (details).
- Native SwiftUI with proper
@Observable view models and an actor-based engine.
- MIT licensed. No ads, no telemetry, no payments.
Install
Homebrew (recommended)
brew install --cask suryansh-codes2209/macget/macget
Requires macOS 26.4 or later on Apple silicon. The cask removes the quarantine
attribute after install, so there is no Gatekeeper prompt and no "Open Anyway" step.
From a release DMG (when v1 ships)
- Download
macget.dmg from the Releases page.
- Open the DMG, drag Macget to Applications.
- Launch from Applications.
Minimum macOS: 26.4 Tahoe.
First launch on macOS
Macget is currently distributed free and un-notarized (no paid Apple Developer
account). On first launch macOS Gatekeeper will say "Macget can't be opened because
Apple cannot check it for malicious software." This is expected — to open it:
- Click Done on the warning.
- Open System Settings → Privacy & Security, scroll down, and click Open Anyway next to Macget.
- Confirm once more — Macget opens normally from then on.
Power-user one-liner instead of the steps above:
xattr -dr com.apple.quarantine /Applications/Macget.app
Auto-updates (via Sparkle) install smoothly after this one-time step.
From source
git clone https://github.com/Suryansh-Codes2209/Macget.git
cd Macget
open Macget.xcodeproj
Then in Xcode: ⌘R to run, ⌘U to test. The .xcodeproj is committed and Sparkle is gated behind #if canImport(Sparkle), so the app builds and runs without any extra setup.
To enable auto-updates (optional): File → Add Package Dependencies… → https://github.com/sparkle-project/Sparkle (≥ 2.6.0).
Updates
After the first install you don't re-download MacGet from this page — it keeps
itself current with Sparkle, the standard
auto-update framework for apps distributed outside the Mac App Store.
- Automatic. On launch MacGet quietly checks its appcast feed on a schedule. When a newer version is published it offers to download and install it.
- Manual. Any time, choose MacGet → Check for Updates… from the menu bar.
- Verified. Every update is signed with an EdDSA key; MacGet checks the signature before installing, so a tampered or corrupt download is rejected. This is independent of Apple notarization — updates are trustworthy even on the free, un-notarized build.
Sparkle is gated behind #if canImport(Sparkle). Auto-updates are active in
release builds that bundle the Sparkle SPM dependency; a from-source build
without it falls back to a Check for Updates… menu item that explains the
dependency is missing.
Maintainers — publishing an update: cut a release (see
Release a DMG), then regenerate the signed feed
with Sparkle/bin/generate_appcast site/ and push site/. GitHub Pages serves
site/appcast.xml at the SUFeedURL above. The EdDSA private signing key
lives only in your login Keychain ("Private key for signing Sparkle updates") —
back it up offline, or you can
never sign another update for existing installs.
Architecture
The download engine is the heart of the app; everything else is glue. Top-level flow for one download:
Probe (HEAD → GET Range:0-0 fallback) → Disk-space check → Plan chunks
→ Open sparse partial file → Spawn workers (staggered)
→ Stream over URLSession → 64 KB writes through FileWriter actor
→ Demote on rapid failures → Finalize → Move into place
Key types (under Macget/Engine/):
| Type | Role |
|---|
DownloadEngine | Top-level actor. Owns all coordinators, schedules per maxConcurrentDownloads, emits an AsyncStream<EngineEvent> to the UI. |
DownloadCoordinator | Per-download actor. Probes, plans, spawns workers, runs the orchestration loop, demotes on rapid failures. |
ChunkWorker | One HTTP-Range request, one attempt. Streams data via an AsyncThrowingStream bridge over URLSessionDataDelegate. |
ChunkPlanner / ChunkSplitter | Static planning: split bytes into ≥ 64 KB chunks, clamped to Download.maxThreadCount. |
FileWriter | Actor wrapping a FileHandle. Serializes positional writes so concurrent chunks don't race. |
RangeProbe | HEAD then ranged-GET fallback. Records Content-Length, Accept-Ranges, ETag, Last-Modified. |
SpeedMeter | 3-second rolling-window throughput + ETA. |
HostCapStore | Persistent per-host parallelism memory. Caps ratchet downward only. |
URLSessionFactory.shared | Single process-wide URLSession — responsiveData QoS, extended background idle mode, httpMaximumConnectionsPerHost = 16. |
For deeper detail, read docs/architecture.md — the full engine walkthrough, object graph, and resume semantics. CLAUDE.md holds the day-to-day conventions for contributors.
Project layout
Macget/
├── Macget/ ← Swift sources
│ ├── App/ ← AppDelegate, AppEnvironment
│ ├── Models/ ← Download, Chunk, Status, Settings
│ ├── Persistence/ ← DownloadStore (queue.json), HostCapStore (host_caps.json)
│ ├── Engine/ ← ★ multi-threaded download engine
│ ├── Services/ ← Clipboard watcher, filename resolver, disk check
│ │ └── Catalog/ ← OPDS parser/client, catalog list (catalogs.json)
│ ├── Updater/ ← Sparkle wrapper (gated)
│ ├── ViewModels/ ← @MainActor @Observable
│ ├── Views/ ← SwiftUI
│ ├── Resources/ ← Info.plist, entitlements, Assets.xcassets, Branding/
│ └── Supporting/ ← os.Logger
├── MacgetTests/ ← XCTest suites (46 tests)
├── MacgetUITests/ ← XCUITest harness
├── scripts/release.sh ← build → DMG → notarize → staple
├── site/index.html ← landing page (deploy via GitHub Pages)
├── .github/workflows/ci.yml ← CI: build + test on push/PR
├── CHANGELOG.md
├── CLAUDE.md ← architecture + conventions
└── Macget.xcodeproj
Build, test, release
Develop
# Build
xcodebuild -project Macget.xcodeproj -scheme Macget -configuration Debug build
# Run all tests
xcodebuild test -project Macget.xcodeproj -scheme Macget -destination 'platform=macOS'
# Run one test class or method
xcodebuild test -project Macget.xcodeproj -scheme Macget -destination 'platform=macOS' \
-only-testing:MacgetTests/ChunkPlannerTests
Release a DMG (scripts/release.sh)
Free, no Apple account: run ./scripts/release.sh --no-notarize. It builds an
ad-hoc-signed DMG (bundling yt-dlp + ffmpeg), skipping the Developer ID and
notarization steps. Sparkle auto-updates still work; users do the one-time
Gatekeeper "Open Anyway" from First launch on macOS.
This needs only brew install create-dmg and the Sparkle key (step 4 below).
Notarized (frictionless install) requires a paid Apple Developer account —
one-time setup:
- Enroll in the Apple Developer Program ($99/yr) and install a Developer ID Application certificate in your Keychain.
- Save notarization credentials:
xcrun notarytool store-credentials "macget-notary" \
--apple-id "[email protected]" \
--team-id "YOUR-TEAM-ID" \
--password "<app-specific password from appleid.apple.com>"
brew install create-dmg- Add the Sparkle SPM dependency in Xcode and run
bin/generate_keys. Copy the printed public key into Macget/Resources/Info.plist's SUPublicEDKey. Back up the private key offline.
Per release:
- Bump Marketing Version + Current Project Version in Xcode's target settings.
- Add an entry to
CHANGELOG.md.
- Run
./scripts/release.sh from the repo root (builds, notarizes, and writes
dist/macget.dmg alongside the versioned dist/Macget-<version>.dmg).
- Create a GitHub Release and attach
dist/macget.dmg as an asset named
exactly macget.dmg — the Sparkle appcast enclosure and the Homebrew cask
URL both depend on that exact name.
- Run
./scripts/publish-cask.sh to push the Homebrew cask to the
tap.
- Run
Sparkle/bin/generate_appcast site/ and push site/ to GitHub Pages.
The CI workflow at .github/workflows/ci.yml runs build + tests on every push/PR.
Contributing
Issues and PRs welcome. The Engine/ directory is the high-stakes code — please include unit tests for any change there, and mirror the actor / @Sendable conventions described in CLAUDE.md.
License
MIT. See LICENSE.
