Backstory: I've been using many agents in parallel as I work on a somewhat ambitious financial analysis tool. I was juggling agents working on epics for the linear solver, the persistence layer, the front-end, and planning for the second-generation solver. I was losing my mind playing whack-a-mole with the permission prompts. YOLO mode felt so tempting. And yet.
Then it occurred to me: what if YOLO mode isn't so bad? Decision fatigue is a thing. If I could cap the blast radius of a confused agent, maybe I could just review once. Wouldn't that be safer?
So that day, while my kids were taking a nap, I decided to see if I could put YOLO-mode Claude inside a sandbox that blocks exfiltration and regulates git access. The result is yolo-cage.
Also: the AI wrote its own containment system from inside the system's own prototype. Which is either very aligned or very meta, depending on how you look at it.
I started Muky in April 2024. Classic side project that got out of hand. We have two kids - the younger one is happy with the Toniebox, but our older one outgrew it. She started asking for specific songs, audiobooks that aren't available as figurines, and "the music from that movie."
We had an old iPad Mini lying around and already pay for Apple Music. Felt dumb to keep buying €17/$20 figurines for 30-45 minutes of content when we have 100 million songs.
Now at version 4.0 after ~20 updates. Some lessons:
On the hardware vs app tradeoff: Toniebox and Yoto are brilliant for little ones – tactile, simple, no screen needed. But they hit a wall once kids want more. And handing a 5-year-old Apple Music means infinite scrolling and "Dad, what's this song about?" Muky sits in between – full library access, but parents control what's visible.
On sharing: Remember lending CDs or cassettes to friends? Or kids swapping Tonie figurines at a playdate? I wanted that for a digital app. So I built QR code sharing. Scan, import, done. And unlike a physical thing – both keep a copy.
On onboarding: First versions: empty app, figure it out yourself. Retention was awful. Now: 4-step onboarding that actually guides you. Should've done this from the start.
On content discovery: 100 million songs sounds great until you have to find something. Parents don't want to search – they want suggestions. Spent a lot of time building a Browse tab with curated albums and audiobooks for kids. Finally feels like the app helps you instead of just waiting for input.
On going native: Went with Swift/SwiftUI instead of Flutter or React Native. No regrets - SwiftUI is a joy to work with and performance is great. Android users ask for a port regularly. No capacity for that now, but Swift for Android is progressing (https://www.swift.org/documentation/articles/swift-sdk-for-a...). Maybe one day. CarPlay is another one parents keep asking for – going native should make that easier to add, if Apple grants me the entitlement.
On subscriptions vs one-time: Started with one-time purchase. Revenue spikes at launch, then nothing. Switched to subscription – existing one-time buyers kept full access. Harder to sell, but sustainable.
Ask me anything about indie iOS dev or building for kids. App is at https://muky.app if you're curious.
NOTE! Turn the volume way down before using the site. It is noise music. :)