Your Mac's Hard Drive: AI Tools Are Eating 20GB of Invisible Trash

阅读中文版 →

Your Mac's Hard Drive: AI Tools Are Eating 20GB of Invisible Trash

Tuesday night, I opened Product Hunt and spotted a tool called DevCleaner. 111 upvotes, 18 comments. Not huge numbers, but I stared at it for ten minutes.

Why? Because its description hit a pain point I feel every month: "Your dev tools and AI apps are hoarding tens of gigabytes of junk data."

I checked my Mac. The ~/Library/Caches folder: 13.2GB. The AI-related directories inside ~/Library/Application Support—Cursor, Claude Desktop, Ollama, LM Studio—added up to 22.7GB.

This isn't a storage problem. It's a money problem.


Translation for Humans

DevCleaner does one simple thing: scans cache files, logs, model caches, and derivative data left by your dev tools and AI apps, then cleans it all with one click.

Sounds like CCleaner, right? Not quite.

Traditional cleaners don't know what "AI model cache" or "dev tool derivative data" is. They'll clear browser cache, but they won't touch the 4 7B model files in ~/.ollama/models—because you downloaded those intentionally, right? The problem is, you downloaded 4 models but only use 2. The other 2 are from testing months ago.

Who's hurting?

Why now?

Three shifts happening simultaneously:

  1. AI tools went from "trying them out" to "daily drivers." A year ago you installed one AI tool. Now you have 5-8. Each one silently hoards data.
  2. Mac storage upgrade costs are rising. Apple charges $200 to go from 256GB to 512GB, then another $200 for 512GB to 1TB. Every 50GB you free up is like "earning" $200.
  3. Dev tools themselves are bloating. VS Code extension cache, Node's node_modules, Xcode's derived data—these are classic pain points. Now add AI cache on top. Double the fun.

Pricing anchor: DevCleaner is free for now, but I see willingness to pay. On Reddit r/MacOS, someone asked "Is there a tool to clean AI cache?" and a commenter said "I'd pay $10 for a one-time purchase for this." On the Product Hunt comments, someone asked "Does it support scheduled cleanup?"—a question only paying users ask.

A reasonable price: $9.99 one-time purchase (competing with CleanMyMac X at $39.95/year, but more focused). Or $3.99/month subscription with auto-cleanup and disk space alerts.


The Real Opportunity Behind This

DevCleaner is a signal, but it's not pointing to "build another cleaning tool." That market's already taken.

The truly overlooked opportunity is: AI tool data management is an unclaimed space.

Specifically:

Product: AI Cache Auditor for Mac

A menu bar app that does three things:

  1. Scan: List all AI tools (Cursor, Claude Code, Ollama, LM Studio, ChatGPT Desktop, Midjourney, ComfyUI) with their cache and model data, grouped by tool, showing how much space each takes.
  2. Tiered Cleanup: Don't delete blindly. Instead, tell the user: "This model was last used 3 months ago—recommend cleaning" (Safe), "This cache is for the current project context—deleting may slow things down" (Caution), "This log file is 2GB and completely useless" (Safe to Delete).
  3. Disk Space Alerts: When free space drops below 20GB, automatically suggest items to clean.

Who'll pay first?

Why most people will miss it:

The mainstream view is: "CleanMyMac is enough."

Wrong. CleanMyMac doesn't know what codeContextCache is inside ~/.cursor/. It'll identify AI model files as "user files" and leave them alone. It doesn't know that Ollama's model cache and Cursor's project cache are two different things.

Another mainstream view: "Hard drives are cheap—no need to clean."

Wrong. The marginal cost of upgrading Mac storage is $200/100GB = $2/GB. Cleaning 20GB = saving $40. And it's not just about money—when disk space runs low, AI tools and IDEs slow down, crash, and stop generating code.


Why Most People Will Miss It

After reading all 18 comments on DevCleaner, I noticed a pattern: Users are asking "Can it auto-clean?" and "Can it support more tools?"—these are signals that say "I want to keep using this." But the developer didn't catch it.

The DevCleaner developer probably treated it as a weekend project—built it, shipped it, done. They didn't realize they'd hit a real, unmet need.

Data backing this up:

Counter-check (when this judgment is wrong):

  1. AI tools start cleaning themselves. For example, Cursor adds "auto-clean cache unused for 30 days" in a future version. This product dies.
  2. Users don't care. Maybe most developers don't sweat 20GB of cache—they bought the 1TB MacBook Pro. The market is smaller than I think.
  3. macOS adds native support. Apple includes AI cache management in macOS 18. Low probability, but possible.
  4. DevCleaner iterates. Its developer reads this article, decides to go full-time, and rapidly builds the version we're discussing. The slow mover loses.

If I Were Doing This

Day 1: Validate who's hurting

Open these 4 places:

Goal: Find 10 real people and ask them: "How much disk space are your AI tools eating? Do you want to clean it? How much would you pay?"

Don't build a product yet. Start with a Google Form, titled: "How much disk space are your AI tools eating?"

Questions:

  1. Which AI tools do you use? (Multi-select: Cursor/Claude Code/Ollama/LM Studio/ChatGPT Desktop/Other)
  2. How much free space is left on your Mac?
  3. When did you last clean your AI cache? (Options: Never/Manually cleaned/Used a tool but it didn't work)
  4. If a tool could safely clean your AI cache, how much would you pay? ($4.99 one-time / $9.99 one-time / $3.99/month / Nothing)

Post this form to the 4 Reddit subreddits + Hacker News "Show HN" + Twitter/X relevant threads. Goal: 100 valid responses in 7 days.

Day 7: Decide

MVP Plan (if you decide to build):

You don't need a full macOS app. Start with a Shell script + a simple web interface.

Script: Scan known directories (~/.cursor/, ~/.ollama/models, ~/.cache/, ~/Library/Application Support/, etc.), output each tool's space usage and last modified time.

Web interface: Write a local server in Go or Node.js, display results in the browser, and include a "Clean Up" button.

Can you build it in 7 days?

Yes. Days 1-2: write the scanning script. Days 3-4: write the web interface. Day 5: test. Days 6-7: send it to those 10 real users for feedback.

Failure conditions:


Other Signals Worth Watching This Week


About AimFast.Dev: Every day, I scan 1000+ signals from Hacker News, Product Hunt, GitHub, Reddit, and more. Using the BuilderPulse E-P-A framework (Evidence Anchoring → Plain Translation → Actionable Advice), I filter down to 1-3 actionable product opportunities. I'm not writing analysis reports—I'm chatting with fellow builders.

Slug: mac-ai-cache-cleaner-opportunity