Development environments / Namespace alternative

A Namespace alternative for agents that need a growing durable computer

Namespace offers returning Linux/macOS Devboxes alongside CI runners, build infrastructure and caching. Devboxes retain persistent storage across stop/start, but their billing units and lifetime caps differ from the platform’s ordinary compute jobs. Compare the actual product rather than price an agent devbox from a runner table.

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Reviewed 2026-10-18 · Published by the Sandbox0 team

When Namespace fits

Namespace fits teams combining remote developer/agent environments with fast builds, managed runners, IDE/SSH access and its broader developer infrastructure. Its Devbox lifecycle supports reconnecting to an existing machine rather than recreating every workspace.

When to consider Sandbox0

Consider Sandbox0 for a hosted Linux agent runtime with whole-RootFS durability, online growth and supported file access during compute pauses. Keep macOS, CI/build services, cache integrations and developer interfaces separate in the architecture and bill.

Capabilities

Namespace and Sandbox0: what persists?

Feature comparison with documentation and verification status
Environment and runtime lifetimeNamespaceBusiness supports up to 24-hour active instances; lower plans have three-/five-hour caps that apply even during activity.View evidence ↗Sandbox0ttl 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 filesNamespaceStop retains persistent storage for a later automatic start; delete removes it.View evidence ↗Sandbox0The writable RootFS survives successful checkpoints, including software, system configuration, dependencies, and user data.Read documentation →
Whole RootFSNamespaceThe guide establishes persistent storage, not uniform complete writable RootFS coverage across all platform/image paths.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 stateNamespaceA stopped Devbox can restart with retained storage; idle and maximum-duration rules still apply.View evidence ↗Sandbox0Pause compute between tasks; resume on available capacity. Default resume starts fresh processes from the saved filesystem.Read documentation →
Memory and process stateNamespaceThe reviewed lifecycle does not establish arbitrary process-memory continuation on start.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.

Persistent Devbox storage is billed on used data, but the reviewed lifecycle does not establish automatic online expansion of a complete durable RootFS. Evaluate the selected image’s storage coverage and resizing path independently of billing capacity.

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.

See paused file operations →

An active connection does not bypass the maximum duration

The Devbox guide separates idle auto-stop from a hard active-instance maximum. Developer and Devbox Plus list three hours, Team five and Business 24. SSH, task markers and protected services can prevent idle, but cannot extend the hard cap. Persistent storage remains for a later start; deletion removes it.

Source 1 ↗

A returning Devbox and a Blueprint are different state

Stop/start retains the Devbox’s persistent storage, and connecting starts a stopped Devbox automatically. A Blueprint saves configuration for creating new Devboxes. Neither the reviewed lifecycle nor that configuration workflow establishes complete filesystem/memory checkpoint coverage across every platform and lifecycle action.

Source 1 ↗

Devbox Minutes do not consume included CI unit minutes

The public price page explicitly bills Devboxes separately from ordinary compute unit minutes. Larger and macOS shapes consume multiple Devbox Minutes. Used persistent bytes are charged separately from compute; the Devbox Plus bundle is a different $250 plan from the standard $250 Business plan.

Source 1 ↗Source 2 ↗

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.

Namespace

Pricing reviewed 2026-10-18

Developer Devbox plan
Pay as you go, no monthly commitment
Rate source ↗
One Devbox Minute
$0.004
Rate source ↗
Linux S / M / L / XL usage
1 / 2 / 4 / 8 Devbox Minutes per minute
Advertised max vCPU boosts differ by shape; they are not equal-throughput reservations.
Rate source ↗
macOS M / L usage
15 / 30 Devbox Minutes per minute
Rate source ↗
Persistent Devbox storage
$0.20 per used GB-month
Used bytes, not provisioned volume capacity.
Rate source ↗
Devbox Plus
$250/month with 50,000 Devbox Minutes and 400 GB-month storage
Different from standard Business/CI plan inclusions.
Rate source ↗

Standard CI/build unit-minute allowances do not include Devbox usage. Preserve GB units, platform multipliers and used-storage basis. Stopped Devboxes still count against per-user/workspace object limits. Advertised maximum vCPU is not an independently measured throughput guarantee.

Check current Namespace 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 Namespace

  1. Export required persistent data and system setup; record platform/image, Blueprint, hard cap, idle/task-marker policy and current Devbox plan.
  2. Port compatible Linux tools, lifecycle, files, credentials and network behavior while retaining required macOS, CI and build/cache integrations.
  3. Validate system-path coverage, online growth, paused file access, process restart expectations and all Devbox-minute/storage charges.

Common questions

Is Sandbox0 a drop-in Namespace 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 ↗namespace.so/docs/devbox/lifecycle.md ↗namespace.so/pricing ↗namespace.so/docs/workspaces/billing-and-limits.md ↗Sandbox0 RootFS capacity →

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