Arr Stack Automation Deep Dive: What You're Missing in 2026

Introduction: The Never-Ending Quest for Media Automation Perfection

You've got your Arr stack running. Sonarr, Radarr, maybe even Lidarr and Readarr. Prowlarr feeds them all. But something feels... incomplete. That's exactly what sparked that Reddit discussion with 409 upvotes and 126 comments—people sharing their setups, asking what they're missing, and honestly, feeling a bit overwhelmed by the possibilities.

I've been there. I've tested dozens of these tools, rebuilt my stack three times last year alone, and learned some hard lessons about what actually works versus what looks good on paper. The post that started this conversation mentioned QUI's built-in cross-seeding shaking things up, Profilarr keeping everything aligned, and that nagging feeling that maybe, just maybe, there's a better way to wire everything together.

Let's fix that. This isn't just another "here's how to install Sonarr" guide. This is about the gaps—the spaces between the tools where automation either shines or stumbles. We're going to build on that Reddit discussion, answer the questions people were really asking, and create a system that doesn't just work, but works well.

The Modern Arr Stack: More Than Just Sonarr and Radarr

First, let's acknowledge something important. The term "Arr stack" has evolved. What started as Sonarr and Radarr has expanded into an ecosystem. Prowlarr changed the game by centralizing indexers. Bazarr handles subtitles. Readarr manages books. Lidarr tackles music. And then there are the support tools—the ones that make everything play nicely together.

But here's the thing most guides miss: More tools don't necessarily mean better automation. In fact, I've seen setups with fifteen different containers that actually perform worse than simpler ones. The key isn't collecting tools like Pokémon. It's understanding how they interact.

Take the original poster's setup: Profilarr managing quality profiles across Sonarr and Radarr. That's smart—it addresses one of the biggest pain points in multi-arr setups. Keeping quality profiles synchronized manually is a nightmare. One change in Sonarr and suddenly your Radarr is downloading 4K remuxes for a kids' cartoon. Profilarr solves that, but it's just one piece.

QUI and the Cross-Seeding Revolution

Let's talk about QUI, since that's what kicked off this whole discussion. For those who missed it, QUI (which stands for Quick Usenet Indexer) introduced built-in cross-seeding capabilities that changed how many of us think about automation.

Cross-seeding, for the uninitiated, is the practice of uploading content you've downloaded to other trackers. It helps maintain ratio, supports communities, and honestly, feels like good digital citizenship. But before QUI's integration, cross-seeding was a manual process or required separate tools like cross-seed.

Now here's what people in that Reddit thread were really asking: "Is QUI's built-in cross-seeding enough, or do I still need separate tools?"

From my testing in 2026: It depends on your tracker mix. QUI handles the basics beautifully for mainstream trackers. But if you're on more specialized or private trackers with specific rules, you might still want a dedicated cross-seed tool running alongside. The beauty is they can work together—QUI catches the easy ones, and your dedicated tool handles the edge cases.

One pro tip I haven't seen mentioned much: Schedule your cross-seeding. Don't let it run constantly. Set it for off-peak hours. Cross-seeding can be resource-intensive, and doing it at 3 AM means your daily downloads won't be affected.

Profilarr: The Silent Hero of Consistency

The original post mentioned Profilarr keeping Sonarr and Radarr aligned. This deserves more attention because profile management is where most automation setups fail silently.

Here's a scenario I've encountered too many times: You set up Sonarr with a "1080p WebDL" profile. Six months later, you add Radarr and create a "4K Remux" profile with the same name but different settings. Suddenly, movies and TV shows have completely different quality targets, and you're wondering why your storage is disappearing.

Profilarr solves this by letting you define profiles once and apply them everywhere. But—and this is crucial—you need to understand how different Arr apps interpret these profiles.

Sonarr and Radarr handle upgrades differently. Sonarr tends to be more aggressive about upgrading existing files. Radarr, in my experience, is more conservative unless you tweak the settings. Profilarr syncs the profile definitions, but it doesn't change how each app behaves with those profiles.

My recommendation? Use Profilarr for the baseline, but then spend time in each app's settings understanding the upgrade logic. Set custom formats and scoring differently per app. A movie might deserve different treatment than a TV episode.

Prowlarr as the Central Nervous System

Prowlarr being the "single indexer source for everything" sounds perfect in theory. And mostly, it is. But the Reddit discussion revealed some edge cases people weren't expecting.

First, indexer priority matters more than most people realize. When you have twenty indexers feeding through Prowlarr, the order they're queried affects everything—download speed, content quality, even ratio maintenance.

I organize mine in tiers:

• Tier 1: Freeleech trackers and usenet providers with good retention
• Tier 2: General private trackers
• Tier 3: Public trackers (as fallback only)

This ensures I'm not burning ratio on something I could get for free elsewhere. Prowlarr lets you set priority, but it's not intuitive. You need to adjust the "priority" field in each indexer's settings, with lower numbers checked first.

Second—and this caught me by surprise—some indexers don't play nicely with Prowlarr's API. They'll work directly in Sonarr but fail through Prowlarr. The solution? Test each indexer individually after adding it. Search for something obscure and see if results come through. Don't assume because it's "added" that it's "working."

The Missing Pieces: What That Reddit Thread Was Really Asking

Reading through all 126 comments, I noticed patterns. People weren't just sharing their setups—they were asking, sometimes indirectly, about the gaps. Here are the most common ones:

1. Notification and alerting: When automation fails silently, you might not know for days. The Arr apps have notification settings, but they're basic. I use a combination of Gotify for mobile alerts and a dedicated Discord webhook channel. Every download, every failure, every upgrade gets logged where I'll actually see it.

2. Storage management: No one in the thread mentioned automated cleanup. Your Arr stack downloads beautifully, but what deletes old content? I use Tdarr for transcoding (which saves space) and a custom script that removes content older than X days based on rules. Kids' shows get kept longer. Prestige TV gets kept forever. Reality TV gets deleted after a month.

3. Quality control: Just because something downloads doesn't mean it's watchable. I've had files with corrupted audio, incorrect aspect ratios, even the wrong movie entirely. Now I run everything through a quick check with FFmpeg. If it fails basic validation, it gets deleted and re-requested automatically.

These aren't "Arr stack" tools per se, but they're what transform a collection of downloaders into a true automation system.

Advanced Workflow: Connecting Everything Together

Let's build on the original poster's rough flow and make it concrete. Here's my current setup, refined after all that testing:

1. Request comes in via Overseerr (for family) or directly in Sonarr/Radarr (for me)
2. Prowlarr checks all indexers based on priority tiers
3. Download client (qBittorrent with specific rules) receives the torrent
4. Sonarr/Radarr imports to the appropriate library folder
5. Automated validation runs via FFmpeg script
6. Tdarr transcodes if needed (usually just for mobile optimization)
7. Notifications fire to Discord and Gotify
8. Cross-seeding begins during off-peak hours
9. Metadata updates in Plex/Jellyfin

The magic happens in the connections between steps. Docker networks ensure everything can talk. Webhooks trigger the next action. And most importantly—error handling at each stage.

If the download fails, it doesn't just stop. The system retries with a different indexer. If import fails, it notifies me immediately. If validation fails, it restarts the whole process. This is what people mean when they say "automation"—not just automatic downloading, but automatic recovery.

Common Mistakes (And How to Avoid Them)

Based on the Reddit discussion and my own experience, here are the pitfalls that trip people up:

Permission nightmares: This is the number one issue in self-hosted setups. Your download client runs as one user, Sonarr as another, and your media player as a third. They all need to read and write the same files. The solution? Consistent UID/GID across all containers. Pick numbers (like 1000:1000) and use them everywhere. Or better yet, use a Docker compose file that defines a shared user.

Path mapping confusion: Docker paths don't match host paths. /downloads in qBittorrent might be /mnt/user/downloads on your host, but Sonarr needs to see it as /downloads too. This is where people lose files—they download successfully but Sonarr can't find them to import. Double-check every path mapping. Test with a small download first.

Quality profile overload: I've seen setups with fifteen quality profiles. That's too many. You'll never remember what "Good 1080p with HEVC but no HDR unless it's Tuesday" means. Keep it simple: SD, HD, 4K. Use custom formats for the nuances (HDR10+, DV, etc.). Your future self will thank you.

Ignoring logs: The Arr apps have detailed logs. Most people never look at them until something breaks. Make a habit of checking logs weekly. Look for patterns—repeated failures from a specific indexer, import errors for certain file types, etc. Catching small issues early prevents big problems later.

Hardware Considerations for 2026

Automation isn't just software. Your hardware affects everything. That Reddit thread had people running Arr stacks on everything from Raspberry Pis to dedicated servers.

Here's what matters in 2026:

• Storage speed over capacity: An SSD for your Arr apps and databases makes everything faster. You don't need terabytes—just enough for the apps themselves. Keep media on slower, larger drives.
• RAM for metadata: Prowlarr and the Arr apps cache indexer results and metadata. 8GB is the new minimum. 16GB lets everything breathe.
• CPU for transcoding: If you're using Tdarr or similar, modern Intel CPUs with Quick Sync handle multiple transcodes simultaneously without breaking a sweat. AMD's equivalent has caught up too.

If you're building a new system specifically for media automation, consider something like the Intel NUC 13 Pro Mini PC. It's small, power-efficient, and has the hardware acceleration modern automation needs. For storage, I prefer WD Red Pro NAS Hard Drives in a proper NAS enclosure.

When to Automate (And When Not To)

This might be controversial, but not everything should be automated. The Reddit discussion hinted at this—people asking about manual overrides, exceptions, and special cases.

I have rules:

• Movies from my favorite directors get manual quality selection
• TV shows still airing get automatic downloads, but I review before deleting
• Documentaries get extra subtitle searching via Bazarr
• Kids' content gets transcoded to smaller files for tablets

The point is: Automation handles the routine. You handle the exceptions. Trying to automate everything leads to complex rules that eventually break.

One specific example: Anime. The anime community has... specific preferences. Fansubs, specific release groups, sometimes even specific encoders. I don't try to automate anime downloads. I have a separate Sonarr instance with completely different indexers and profiles, and I manually approve most downloads. The automation here is just notification—telling me something is available, not downloading it automatically.

Future-Proofing Your Setup

Looking ahead to 2026 and beyond, here are trends affecting Arr stacks:

AI-assisted metadata: Tools are starting to use AI to fix incorrect metadata, match files that don't have proper naming, even identify content visually. This reduces manual correction.

Better integration standards: Webhooks are becoming more standardized. The Arr apps now support more specific events ("download failed due to ratio limits" vs just "download failed").

Containerization improvements: Docker Compose is being replaced by more powerful orchestration for home users. Portainer stacks make management easier. Updates are becoming less disruptive.

My advice? Keep your configuration in version control. Use Docker Compose files (or similar) that are documented. When a new tool emerges, you can test it in isolation without breaking your main system.

If you're not comfortable with the technical side, consider hiring someone to set up the initial system. Platforms like Fiverr have experts who can create a stable Arr stack foundation you can maintain yourself. Just make sure they document everything.

Conclusion: Building Your Perfect System

That Reddit thread asked "What am I missing?" The answer, as we've seen, isn't one tool or one setting. It's the connections between tools, the error handling, the monitoring, and the understanding that automation is a process, not a destination.

Start with the basics: Sonarr, Radarr, Prowlarr. Get them working reliably. Then add one enhancement at a time. Profilarr for consistency. Better notification. Automated cleanup. Cross-seeding. Test each addition thoroughly before moving to the next.

Remember—the goal isn't to eliminate all manual intervention. It's to eliminate the boring, repetitive tasks so you can focus on the interesting parts. Your media collection should bring joy, not maintenance headaches.

The most successful setups I've seen (and the one I run today) balance automation with control. They download automatically but notify on completion. They clean up old files but ask before deleting favorites. They're tools that work for you, not systems you work for.

Now go check your logs. I'll bet there's at least one indexer failing silently. Fix that first. Then come back and tackle the next gap. Your future self, enjoying seamlessly automated media, will thank you.