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Deep Unfreeze - Services That Sleep for Decades

January 05, 2026

Deep Unfreeze: Services That Sleep for Decades

What happens to your cloud service when you stop paying? Most providers delete everything after 30-90 days. Your data, your configuration, your work. All gone.

We built something different.

The Problem with Cloud Expiration

Traditional cloud services have a simple lifecycle:

  1. You pay. Service runs.
  2. You stop paying. Grace period (maybe).
  3. Grace period ends. Data deleted forever.

This makes sense for the provider because storage costs money. But itโ€™s terrible for users who might want to come back someday.

Deep Freeze: Suspended Animation for Services

When your unsandbox API key expires, your services donโ€™t die. They enter deep freeze:

  • Container state preserved (frozen, not deleted)
  • All data intact on disk
  • Configuration saved
  • DNS records maintained
  • Justโ€ฆ sleeping

The service consumes minimal resources in this state. Itโ€™s like cryogenic storage for your code.

The Wake-Up Call

Hereโ€™s where it gets interesting. When someone visits your frozen service (say, minecraft.on.unsandbox.com), they see a page like this:

This service is paused

The hosting subscription has expired.
Renew to bring it back online.

[Renew Subscription]

https://unsandbox.com/keys/extend?key=unsb-pk-xxxx-xxxx-xxxx-xxxx

Use this link on any device to renew.

That button links directly to the payment page with the public key pre-filled. The URL can be copied and used on any device.

Anyone Can Pay the Toll

The public key is embedded in the URL. This means:

  • You can extend it when youโ€™re ready
  • A friend can gift you service time
  • A random visitor who wants your service back online can pay
  • Someone in 2041 who finds your old project can resurrect it

Once payment confirms (speed varies by cryptocurrency or credit card), the service wakes up automatically. Container unfreezes, processes resume, traffic flows.

Why This Matters

Preservation of Digital History

That game server you ran in college? The demo site for your startup that didnโ€™t make it? The hobby project you abandoned? They donโ€™t have to disappear.

Graceful Degradation

Instead of hard failures & data loss, expired services show a helpful page explaining what happened & how to fix it.

Community Revival

Open source projects, community servers, shared resources. Anyone who cares enough can keep them alive.

Long-Term Archival

Weโ€™re not promising โ€œforeverโ€ (nothing is forever), but weโ€™re promising โ€œas long as we exist, your frozen service exists.โ€

Technical Implementation

When a wake attempt hits a deep-frozen service:

  1. Proxy receives request for *.on.unsandbox.com
  2. Lookup service: Found, but sleeping
  3. Check account status: API key expired
  4. Return 402 Payment Required with extend URL
  5. User pays: Key extended
  6. Next request: Service wakes (container unfreezes)
  7. Traffic flows normally

The whole system is lazy. We donโ€™t proactively wake services. The first request after payment triggers the thaw.

Automatic OS Upgrades

A service frozen in 2026 runs Ubuntu 24.04. If it wakes in 2041, that OS is 12 years past end-of-life. Running ancient, unpatched software isnโ€™t an option.

We handle this automatically for all supported operating systems:

OS Upgrade Method
Ubuntu LTS chain via do-release-upgrade
Debian Stable releases via apt full-upgrade
Fedora Version chain via dnf system-upgrade
Alpine Minor versions via apk upgrade
FreeBSD Releases via freebsd-update
OpenBSD Versions via sysupgrade
Arch Rolling updates via pacman -Syu

Freeze Wake (Active Account)

When you wake a service from regular freeze (account still active), we upgrade to the next version if one is available:

Ubuntu:  24.04 โ†’ 26.04
FreeBSD: 14.0 โ†’ 14.1
Alpine:  3.20 โ†’ 3.21

One hop. Fast. Keeps your services reasonably current.

Deep Freeze Wake (Account Revived)

When a service wakes from deep freeze (account was expired, then revived), we chain upgrade to the latest supported version:

Ubuntu:  24.04 โ†’ 26.04 โ†’ 28.04 โ†’ 30.04 โ†’ ... โ†’ 40.04
FreeBSD: 14.0 โ†’ 14.1 โ†’ 14.2 โ†’ 15.0 โ†’ ... โ†’ 16.0
Alpine:  3.20 โ†’ 3.21 โ†’ 3.22 โ†’ ... โ†’ 3.30

The 2041 Minecraft server gets all the hops it needs. Takes longer, but comes up fully patched.

Service States During Upgrade

The CLI and web console show exactly whatโ€™s happening:

$ un service --list

SERVICE ID                       NAME       STATUS           PORTS  DOMAIN
unsb-service-a1b2c3d4e5f6g7h8    minecraft  upgrading        25565  minecraft.on.unsandbox.com
                                            24.04 โ†’ 26.04

For deep freeze upgrades:

SERVICE ID                       NAME       STATUS           PORTS  DOMAIN
unsb-service-a1b2c3d4e5f6g7h8    minecraft  deep_upgrading   25565  minecraft.on.unsandbox.com
                                            28.04 โ†’ 30.04 (4/8)

Progress Screen

Visitors to a waking service see the upgrade progress:

Service is waking up...

โ”Œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”
โ”‚ OS Upgrade in Progress                     โ”‚
โ”‚                                            โ”‚
โ”‚ โœ“ 24.04 โ†’ 26.04                            โ”‚
โ”‚ โœ“ 26.04 โ†’ 28.04                            โ”‚
โ”‚ โ— 28.04 โ†’ 30.04  [โ–ˆโ–ˆโ–ˆโ–ˆโ–ˆโ–ˆโ–ˆโ–‘โ–‘โ–‘โ–‘โ–‘โ–‘โ–‘โ–‘]  47%    โ”‚
โ”‚ โ—‹ 30.04 โ†’ 32.04                            โ”‚
โ”‚ โ—‹ 32.04 โ†’ 34.04                            โ”‚
โ”‚                                            โ”‚
โ”‚ This service was frozen for 15 years.      โ”‚
โ”‚ Upgrading through 5 Ubuntu LTS releases.   โ”‚
โ”‚                                            โ”‚
โ”‚ Estimated time remaining: ~12 minutes      โ”‚
โ””โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”˜

Your data is safe. The service will start automatically.

Why Not Just Use the Old OS?

Running Ubuntu 24.04 in 2041 would be:

  • Security risk: 12 years of unpatched vulnerabilities
  • Compatibility nightmare: Modern TLS, DNS, packages wonโ€™t work
  • Repository dead: Canโ€™t install new software

The upgrade ensures your service runs on a supported, secure OS while preserving your data and configuration.

What About My App?

Your bootstrap script runs after the OS upgrade. Most apps survive fine:

  • Java apps: JVM is stable across versions
  • Python/Node/Ruby: May need version bump in bootstrap
  • Static binaries: Usually work
  • Compiled from source: Bootstrap recompiles

If your app needs adjustment, update your bootstrap script and redeploy. Your data is still there.

What Gets Preserved

Everything:

  • Container filesystem - Your code, data, logs
  • Environment variables - Configuration & secrets
  • Port mappings - Same URLs work after wake
  • Bootstrap scripts - Service knows how to start itself
  • Custom domains - DNS stays configured

What we donโ€™t preserve:

  • Running processes - Container was frozen, processes restart
  • In-memory state - RAM is cleared (design your service accordingly)
  • Active connections - WebSockets, SSH sessions, etc. need reconnection

Pricing Philosophy

Deep freeze storage is cheap. Weโ€™re not charging you for frozen containers since they use negligible resources. The cost is in the wake-up: when your service runs, you pay for compute.

This aligns incentives:

  • Frozen = Free (practically)
  • Running = Pay as you go
  • Wake up whenever youโ€™re ready

The 15-Year Minecraft Server

Imagine this scenario:

2026: You set up a Minecraft server for your kids. They play for a summer, then move on. Your API key expires in December.

2027-2040: Server sits frozen. You forget about it. We keep the container.

2041: Your kid, now an adult, finds the old server URL in their bookmarks. They visit minecraft.on.unsandbox.com, see the frozen page, pay $5 in whatever cryptocurrency exists then, andโ€ฆ

The world loads. Their childhood builds are still there. The chest they filled with diamonds. The house they built together.

Thatโ€™s deep unfreeze.

CLI Experience

For developers using the un CLI:

$ un service --unfreeze my-frozen-service

Error: deep_freeze
API key expired. Service cannot wake until key is extended.

Extend your key: https://unsandbox.com/keys/extend?key=unsb-pk-xxxx-xxxx-xxxx-xxxx

Your service data is preserved and waiting.

Clear, actionable, with the exact URL to fix it.

Comparison: Other Providers

Provider After Expiration Data Retention Revival
AWS Suspended, Deleted 30-90 days No
GCP Suspended, Deleted 30 days No
Heroku Deleted Immediate No
DigitalOcean Suspended, Deleted 30 days No
unsandbox Deep Freeze Indefinite Anyone can pay

FAQ

Q: How long will you keep frozen services? A: As long as unsandbox exists. We have no automatic deletion policy for frozen containers.

Q: Is there a storage limit? A: 7GB per concurrency slot, measuring only your data (copy-on-write means the base OS image doesnโ€™t count against you). With max 8 concurrency, thatโ€™s 56GB total capacity per account.

Q: Can I export my data while frozen? A: Not directly. The container is frozen. Pay to wake it, then export.

Q: What if unsandbox shuts down? A: Weโ€™d provide export tools & advance notice. Your data wouldnโ€™t just vanish.

Q: Can I prevent others from waking my service? A: The service is locked to your account. Others can pay to extend YOUR key, but they donโ€™t get access to manage the service.

Q: Can free tier keys be extended? A: No. Free tier keys are one-time use and cannot be extended. To use deep freeze, you need a paid API key. This ensures frozen services are backed by accounts with payment history.

Q: What payment methods can wake a service? A: Bitcoin, Litecoin, Dogecoin, Monero, or credit card. Crypto wake happens after confirmations (speed varies by chain). Credit card payments process immediately.

Q: Can I disable the freeze page? A: Yes. Set show_freeze_page: false in your service config via CLI or web console. Visitors will get a simple JSON error instead.

Q: What happens to the OS when my service wakes up? A: We automatically upgrade Ubuntu to a supported LTS version. For regular freeze (account active), we upgrade one LTS version. For deep freeze (account was expired), we chain upgrade to the latest LTS. Your data is preserved throughout.

Q: How long does the OS upgrade take? A: One LTS hop takes 5-10 minutes. Deep freeze wakes with multiple hops take longer. A 15-year-old service might need 30-60 minutes for 8 LTS upgrades. The progress screen shows exactly whatโ€™s happening.

Q: What if my app breaks after the OS upgrade? A: Your data is safe. Update your bootstrap script to handle the new OS (e.g., install a newer Python version) and redeploy. The upgrade preserves your filesystemโ€”only the base OS changes.

Q: Can I skip the OS upgrade? A: No. Running end-of-life operating systems is a security risk. The upgrade is automatic and required for wake.

Q: What service states indicate an upgrade? A: upgrading means a single LTS hop (freeze wake). deep_upgrading means chaining through multiple LTS versions (deep freeze wake). Both show progress in the CLI and web console.

Conclusion

Most cloud services treat expiration as deletion. We treat it as hibernation.

Your services can sleep for years, decades even, and wake up when someone decides theyโ€™re worth reviving. Data preserved. Configuration intact. Ready to run.

Because sometimes the most valuable things are the ones we forgot we had.

Pay the toll. Wake the service. Pick up where you left off.

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