KubeSail has stopped its hosted services and no longer accepts new users or sells hardware. Open-source code and PiBox documentation remain. Read the source ↗

Application platforms / KubeSail (retired hosted service) alternative

KubeSail alternative after hosted service closure

KubeSail’s official site says it has stopped operating hosted services and is no longer accepting new users or selling hardware. Open-source code and PiBox documentation remain. Treat this as a migration decision from an existing setup, rather than a comparison with an available new hosted subscription.

Start buildingCompare capabilities ↓

Reviewed 2026-10-19 · Published by the Sandbox0 team

When KubeSail (retired hosted service) fits

Existing operators may keep useful hardware and independently maintain the remaining code where appropriate. That requires checking which local applications, routing, backups and other dependencies still work without the retired hosted service.

When to consider Sandbox0

Consider managed Sandbox0 for compatible Linux agents needing a durable whole writable RootFS, automatic online growth and supported paused files. It is not a substitute for every home-server application or physical PiBox function.

Capabilities

KubeSail (retired hosted service) and Sandbox0: what persists?

Feature comparison with documentation and verification status
Environment and runtime lifetimeKubeSail (retired hosted service)Not established in this reviewSandbox0ttl and hard_ttl default to 0 (disabled). Configure idle pause and deletion policies for the same persistent sandbox identity; an idle running sandbox still accrues compute charges.Read documentation →
Persistent filesKubeSail (retired hosted service)Legacy documentation describes selected PVC backups; actual continuing backup/service access must be checked after closure.View evidence ↗Sandbox0The writable RootFS survives successful checkpoints, including software, system configuration, dependencies, and user data.Read documentation →
Whole RootFSKubeSail (retired hosted service)A selected-volume backup does not establish full writable container RootFS retention.View evidence ↗Sandbox0Persistence extends beyond /workspace to paths such as /usr/local, /etc, and /home. Runtime tmpfs and virtual filesystems are excluded.Read documentation →
Release compute, keep stateKubeSail (retired hosted service)Remaining cluster documentation does not establish an active managed agent pause/resume service.View evidence ↗Sandbox0Pause compute between tasks; resume on available capacity. Default resume starts fresh processes from the saved filesystem.Read documentation →
Memory and process stateKubeSail (retired hosted service)Legacy persistent-volume backups do not establish arbitrary running-process or RAM recovery.View evidence ↗Sandbox0Experimental memory checkpoints can preserve compatible process state. Use memory: true on both pause and resume on a compatible deployment. A filesystem checkpoint alone does not preserve running processes.Read documentation →

Online RootFS growth

On growth-enabled images, Sandbox0 automatically expands the writable RootFS as free space runs low, within a configured sparse logical ceiling up to 64 TiB. Agent processes keep running. Growth is enabled in the qualified Cloud region; confirm activation for other regions. Existing images and snapshots retain their captured storage geometry. The ceiling is logical capacity, not preallocated host disk.

Legacy cluster PVCs and backups retain selected data. An operator can implement storage expansion, but the remaining documentation does not establish a currently operated hosted policy for automatic online whole-RootFS growth.

Files while compute is paused

Sandbox0's Files API reads persistent files without resuming compute. Filesystem-only pauses also permit edits; retained-memory pauses are read-only and reject mutations with 409. SSH, SFTP, file watching, and runtime-only mounts require running compute.

Existing hosts and independent storage tools may access retained volumes without starting an agent container. That operator-owned workflow and legacy backup service are distinct from a current native API spanning a paused agent’s durable RootFS.

See paused file operations →

Hosted availability changed

The official farewell page describes KubeSail’s 2019–2025 history and the end of hosted operations, signups and hardware sales. Remaining code or documentation does not constitute a currently purchasable hosted plan. Establish which replacement services an existing installation actually needs.

Source 1 ↗

Legacy backups target selected persistent volumes

The remaining backup guide describes encrypting data on the cluster, uploading it to S3-backed storage and restoring a selected PersistentVolumeClaim. That preserves selected mounted data, not a blanket guarantee for every writable container OS path or live process.

Source 1 ↗

Separate the agent from the rest of the cluster

A self-hosted cluster can run more than agent workloads. Inventory local apps, ingress, devices, data volumes and backup access before migration. Move compatible Linux agent stages only where the target runtime fits, and retain unrelated hardware-dependent services on suitable infrastructure.

Source 1 ↗

Pricing

Compare billing models, then price your workload

CPU allocation, memory, billing minimums, disk, plan fees, and supported workload differ. These meters are not equal-performance machine quotes. Confirm region, resource units, and included allowances before estimating a total.

KubeSail (retired hosted service)

Pricing reviewed 2026-10-19

New KubeSail hosted subscription
Unavailable: hosted services stopped
The official site says no new users or hardware sales.
Rate source ↗
Existing hardware and independent operations
Actual operator costs
Remaining code is not an active hosted-service tariff.
Rate source ↗
Legacy backup subscription references
Historical; confirm existing data access
Old plan limits in remaining docs are not a current purchasable offer.
Rate source ↗

Do not use remaining Starter/Teams documentation as a current price quote. Confirm export and backup availability for an existing installation before relying on hosted endpoints. Replacement hardware, networking and backup services need separate pricing.

Check current KubeSail (retired hosted service) pricing ↗

Sandbox0

$0.015/GiB-hour compute (billed by the second at approximately $0.000004167/GiB-second), plus $0.02/GiB-month of retained incremental RootFS and memory checkpoint data. Shared base images and platform recovery retention are excluded; paused sandboxes accrue storage charges only.

Compute / GiB-hour
$0.015
Retained data / GiB-month
$0.02
Paused compute
$0.00

A 4 GiB agent, 100 running hours

$6.00 compute

4 GiB × 100 hours, billed by the second. Keeping 20 GiB of billable incremental data for a full billing month adds $0.40. CPU is derived from memory by the platform; choose a tier that fits your workload.

Understand storage billing →

Before migrating from KubeSail (retired hosted service)

  1. Inventory existing hardware, local workloads, PVCs, routing and dependencies on retired KubeSail endpoints; verify export and backup access first.
  2. Export consistent required files and recreate compatible Linux agent setup and network policy; retain unrelated local/device workloads separately.
  3. Test returning agent state, growing outputs, paused files and replacement runtime, storage, networking and hardware costs.

Common questions

Is Sandbox0 a drop-in KubeSail (retired hosted service) replacement?

Evaluate API compatibility and product scope. These products serve different core workflows, so a change may require a different architecture.

Does keeping files also keep a running agent?

Filesystem state and volatile process state are separate. Sandbox0 requires explicit compatible memory checkpoints to preserve running processes; its default filesystem resume starts fresh processes.

Sources and review scope

The Boat team's Battleships directory is the discovery source. References below describe the product and plan discussed on this page. Check current availability, regional terms and billing units before migrating. Where the cited material does not establish a capability or price, the comparison identifies that uncertainty.

Battleships research record ↗kubesail.com/ ↗docs.kubesail.com/backups/ ↗docs.kubesail.com/ ↗Sandbox0 RootFS capacity →

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