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Code & AI agent sandboxes: read the guide

smolvm

Open coreSandbox

Branchable microVMs for AI agents.

Scanned 12 Oct 2026 · Schema v5 · features v21

From
$20/mo

Hosted plan fee plus metered base running time, active vCPU, RSS memory, used disk and egress. Standard $0, Pro $20/month, Startup $150/month, Enterprise custom. OSS engine free under Apache-2.0 plus own infrastructure.

Free tier
Not documented

Standard has $0 monthly plan fee and one-time $100 signup credit, no card. Pricing page + public JSON agree; cloud quickstart still says $10 monthly free usage, so recurring free credit is not treated as current.

Isolation
Virtual machine

hypervisor, or nothing at all

Regions
—

Country-level disclosure: Google Cloud US regions and data processed in United States. Exact hosted regions and placement choices not public; no multi-region availability inferred. Self-host placement is operator-defined.

Capabilities
19 / 61

6 partial · 36 fail · 0 not assessed

Agent readiness
10/11 · 9/11

read · drive, pre-login surface

Advertised for

Untrusted/generated code, persistent coding agent workspaces, warm branch fan out, portable dev/CI environments, Linux services, headless browsers; local Vulkan desktop/computer use and CUDA training/inference.

Built for

Developers, then technical

  • · CLI/API/SDK-first onboarding and code examples
  • · Own-kernel microVM, branch/checkpoint, egress and GPU terminology
  • · Usage-metered compute and memory pricing

01 Pricing Hosted plan fee plus metered base running time, active vCPU, RSS memory, used disk and egress. Standard $0, Pro $20/month, Startup $150/month, Enterprise custom. OSS engine free under Apache-2.0 plus own infrastructure.

Tier EntrystandardprostartupTopenterprise
Price $0/month + usage$20/month + usage$150/month + usagecustom
Includes 20 machines; up to 8 vCPU/16 GB per machine; disk cap not published; idle apps scale to zero; one-time $100 signup credit, no card.100 machines; up to 16 vCPU/24 GB/200 GB disk each; always-on apps; 99.95% uptime SLA.1,000 machines; up to 32 vCPU/32 GB/200 GB disk each; priority support; always-on apps; 99.95% uptime SLA.Contractual limits, dedicated nodes, volume rates, 99.95% SLA and SSO/SAML.
Transfer overage $0.05/GB$0.05/GB$0.05/GB—
vCPU hours overage $0.05/h$0.05/h$0.05/h—
Compute hours overage $0.04/h$0.04/h$0.04/h—
Memory gb hours overage $0.0162/h$0.0162/h$0.0162/h—

Free tier: Standard has $0 monthly plan fee and one-time $100 signup credit, no card. Pricing page + public JSON agree; cloud quickstart still says $10 monthly free usage, so recurring free credit is not treated as current.

Machine-hour $0.04 (1-minute minimum), active vCPU-hour $0.05, active memory GB-hour $0.0162, used disk GB-hour $0.0001, egress GB $0.05. Exec/file I/O $0.·Card required: unconfirmed·smolmachines.com

Overages: All usage is metered at published rates. Graduated 10% discount applies only to spend above $2,000/month; stopped machines billed only held used disk. Plan fee additional.

02 Runtime Each fact carries its source; dots show confidence. Open a row for the evidence.

Isolation & lifecycle

Isolation primitive
Virtual machinehypervisor, or nothing at all
Persistence
Both local ephemeral runs and persistent machines. Cloud filesystem survives exec and stop/start; /tmp, /run and /dev/shm are memory-backed and reset on restart. Delete removes storage; stop is not a backup.
Snapshots / forks
Local live copy-on-write branches preserve RAM, processes and disks. Portable checkpoints and pause/resume are documented, with version/device/architecture constraints; current repo documents arm64 Mac-to-Linux restore and Windows checkpoints plus --freeze-source branches. Cloud branches are node-local; REST snapshots return 501, while separate checkpoint CLI routes are documented. Broad local/cloud live migration is not established.

Resources & limits

Storage
Persistent cloud machine filesystem sized by storageGb; memory-backed paths reset on stop. Local host-directory mounts and packed .smolmachine files. Cloud has no host mounts; generated legacy volume routes are not a supported storage API. No first-party object-storage service documented.
Limits & quotas
Local default 4 vCPU/8 GiB elastic RAM. Hosted Standard: 20 machines, 8 vCPU/16 GB per machine (disk cap unpublished); Pro: 100 machines, 16 vCPU/24 GB/200 GB; Startup: 1,000 machines, 32 vCPU/32 GB/200 GB; Enterprise contractual. Quota failures identify the plan limit. VM count is capacity/concurrency, not monthly sandbox-creation throughput.
GPU
Local/self-host only: Vulkan via virtio-gpu/Venus and CUDA API remoting over vsock. Needs compatible host graphics stack or NVIDIA GPU/driver. CUDA sharing is not hardware-partitioned GPU isolation. Cloud create API has no GPU resource fields; native Windows GPU acceleration unavailable.

Access

Deploy interface
clisdkapicontainer-imagetemplate
SDK languages
Node/TypeScript and Python smolmachines packages; embeddable Rust smolmachines crate. smol Machine API targets embedded local engine or cloud; older smolvm-sdk targets smolvm serve REST.

Network & secrets

Egress controls
Local networking off by default; hostname/subdomain and CIDR allowlists, exact/glob host patterns, runtime updates. Cloud supports explicit blocked/open/allowCidrs modes; SDK cloud default is open, so local isolation-by-default does not imply cloud egress blocked by default. No first-class deny-list documented.
Secrets
Local --secret-env/--secret-file inject readable plaintext; SSH-agent forwarding keeps key bytes on host but permits signatures. --credential and Smolfile network.credentials replace guest placeholders only on authorized HTTPS destinations so real secrets stay outside guest. No cloud-native secrets vault documented.
Bring your own cloud
na

Placement & use

Jurisdiction
United States: privacy policy says Google Cloud US regions and data processed in the United States. No exact hosted region codes disclosed. Self-host jurisdiction follows operator placement.
Advertised workloads
Untrusted/generated code, persistent coding-agent workspaces, warm branch fan-out, portable dev/CI environments, Linux services, headless browsers; local Vulkan desktop/computer-use and CUDA training/inference.

03 Capabilities 19 pass · 6 partial · 36 fail · 61 of 61 assessed

  • Supported
  • Partially supported
  • Not supported
  • Not assessed

Compute & storage 7/11

Persistent diskStorage that survives restart/stop (not ephemeral-only).
Supported
Object storageManaged S3-compatible / blob object store the platform PROVIDES to a user's workloads (buckets, presigned URLs). DISTINCT from persistent-disk (block/volume attached to an instance) and from a self-host dependency (source.self_host.deps[]=["object-storage"] is an infra dep to RUN an OSS tool — the opposite direction). SCOPE varies and matters: native first-class (Railway Buckets, Cloudflare R2) vs a sibling SKU / extension (Fly Tigris, Bunny Storage, DigitalOcean Spaces) — record which in the evidence quote / note. Admitted v15.
Not supported
Snapshots / forkingSnapshot or copy-on-write fork of a running instance (filesystem-only counts). Whether the snapshot also restores memory + running processes is recorded separately by memory-snapshot (v19).
Supported
Live-state (memory) snapshotsA snapshot / checkpoint / pause captures a running instance's MEMORY and PROCESS state and restores it, so running processes continue where they left off instead of a freshly booted instance with the same files. Counts whether user-triggered (snapshot, checkpoint, pause-to-storage) or used to restore pre-initialised state (memory snapshots for fast cold starts). Distinct from snapshots-forks (any snapshot or fork, including filesystem-only; a product passing that key may still fail this one) and from scale-to-zero (an idle-cost property; suspension may or may not keep memory). Actor multiplexing (see scale-to-zero) records its live-state half here — only when the suspended actor's MEMORY/process state is what comes back, not a freshly booted worker with the actor's files.
Supported
Scale to zeroIdle instances suspend at no / negligible cost. ACTOR MULTIPLEXING (many suspended stateful actors sharing a small pool of pre-warmed workers, woken on request — Agent Substrate, AX, kagent; Rivet's hibernating actors) has NO key of its own (proposal REJECTED v20) — score the idle-cost half HERE and the live-state half under memory-snapshot; the oversubscription ratio / density is a performance characteristic the registry does not key.
Supported
GPU computeGPU-backed instances available.
Supported
Multi-regionCompute placeable in more than one geographic region.
Not supported
Sandbox templates / custom imagesBuild reusable sandbox/VM images from an OCI image or Dockerfile (a base you fork instances from).
Supported
Cloud-init / ignition configCustomise a VM / microVM / instance at boot via cloud-init (or ignition) user-data — the same boot-metadata interface as AWS/Azure/GCP. Inject packages, users, SSH keys, files, and run-commands declaratively at launch. Distinct from sandbox-templates (a PREBUILT image you fork instances from) — this is PER-LAUNCH declarative customisation, not a baked image.
Partially supported
Desktop / computer-use sandboxA virtual desktop (GUI) for LLM computer-use — browser + desktop automation, often via noVNC/VNC.
Supported
Selectable isolation runtimeThe user chooses the isolation runtime per workload / environment / sandbox from more than one option (e.g. microVM vs gVisor vs plain container, native namespaces vs gVisor, gVisor vs VM). Records the CHOICE; the isolation_primitive facet still records the best-evidenced primary. A platform that switches runtime automatically without a user choice (e.g. gVisor forced for GPU) does not pass on that alone.
Not supported

Networking & delivery 3/9

Automatic HTTPSTLS endpoints provisioned automatically per workload.
Not supported
Built-in reverse proxyPlatform routes external traffic to workload services.
Supported
Custom domainsBring-your-own domain via CNAME/DNS.
Not supported
Public preview URLsShareable per-deploy / per-branch URLs.
Supported
Direct public IPv6Per-instance stable public IPv6 for raw TCP/UDP (beyond a managed HTTPS proxy) — e.g. mosh / raw sockets.
Not supported
Egress controlsConfigurable OUTBOUND network policy — egress firewall / allowlist / egress proxy on traffic LEAVING a workload. Scoped to OUTBOUND only (v15): private-network REACHABILITY between a user's own services is private-networking, not this. Static-egress-IP belongs here (an outbound concept).
Supported
Private networkingA platform-internal private network between a user's OWN services — service-to-service connectivity, VPC, service mesh, and/or service discovery, not exposed to the public internet. DISTINCT from egress-controls (OUTBOUND firewall/allowlist), reverse-proxy (PUBLIC inbound ingress), and direct-ipv6 (per-instance PUBLIC addressing). Admitted v15.
Not supported
Email send / receiveSend and/or receive email from the workload.
Not supported
Edge KV storeA globally-replicated key-value store read from WITHIN an edge runtime at the PoP (low-latency, eventually-consistent) — Cloudflare Workers KV, Deno KV, Fastly KV Store, Akamai EdgeKV, Vercel Edge Config. Distinct from first-party-db (a managed DATABASE service you provision and connect to) and from http-query-api (HTTP access to an external store) — edge-kv is colocated with the edge compute and read at the edge.
Not supported

Developer access 5/10

Public APIDocumented programmatic API.
Supported
OpenAPI specMachine-readable OpenAPI / Swagger spec published.
Supported
CLIOfficial command-line tool.
Supported
SDKOfficial client library/libraries.
Supported
SSH accessDirect SSH into workloads.
Not supported
Filesystem APIRemote file operations over the API (list/read/write/watch/copy/upload) without SSH.
Supported
Git deployDeploy from a Git repo / push-to-deploy.
Not supported
Private container registryHosted private image registry.
Partially supported
E2B-compatible APIDrop-in compatibility with the E2B sandbox API/SDKs — existing E2B client code runs against this product by changing the endpoint/domain + key, with no business-code changes. E2B itself passes as the reference implementation. Distinct from public-api / sdk (the product has its own API — this key says it also speaks another vendor's) and from self-host-oss (a self-hosted E2B-compatible server is scored on both).
Not supported
HTTP data APIQuery / read / write the stored DATA over plain HTTP/REST (or GraphQL) WITHOUT the native protocol driver (Postgres wire / Redis RESP) — agent- and edge-friendly data access via fetch(). The DATA plane; distinct from public-api (a control-plane / management API). Auto-generated-from-schema REST/GraphQL (PostgREST, pg_graphql) is a flavour of this.
Not supported

AI & agents 3/12

Built-in coding agentShips a first-party AI coding agent in the product.
Not supported
Agent skillsInstallable / declarable agent skills or tools.
Supported
AI app builderPrompt-to-app / vibe-coding generation surface.
Not supported
MCP serverExposes a Model Context Protocol server for agents.
Not supported
MCP clientActs as an MCP client / consumes MCP tools.
Not supported
MCP-server hostingRun/host MCP servers as a workload on the platform (distinct from exposing a first-party MCP control server — that is mcp-server).
Not supported
LLM gatewayRoutes LLM API calls through the platform (multi-provider).
Not supported
BYOK for LLMsBring-your-own LLM provider keys.
Not supported
Model inference API (first-party)A FIRST-PARTY hosted LLM/model inference API — the provider serves its OWN catalogue of (usually open-weight) models behind a (typically OpenAI-compatible) endpoint, billed per token. Distinct from llm-gateway (a multi-PROVIDER proxy/router for YOUR calls to external providers like OpenAI/Anthropic) and from byok-llm (bring your own provider keys) — here the platform IS the inference provider, serving its own models.
Not supported
Autonomous QA agentA first-party AUTONOMOUS AI agent that QA-TESTS a running app / implementation — exercising it like a real user (clicking through flows, checking behaviour) and reporting bugs/defects (often back to a coding agent, or before a human review). Distinct from built-in-agent (a code-AUTHORING agent — this one VERIFIES the result, it does not write the feature; a product can ship both), from ai-guided-code-review (organises a diff for a HUMAN to review — not an autonomous tester), and from observability (runtime metrics/logs, not active testing).
Not supported
Credential-injection proxyThe platform holds real secrets OUTSIDE the workload and injects them on the wire (an egress / broker proxy swaps a placeholder or phantom token for the real credential on matching outbound requests), so code running in the sandbox — e.g. an untrusted agent — never sees or can exfiltrate the real key. Distinct from secrets-management (storage + injection INTO the workload as env vars/files — the workload holds the secret) and from egress-controls (outbound allow/deny POLICY; a product can have an allowlist without injecting credentials, and vice versa).
Supported
Preinstalled coding agentThe platform installs and launches a THIRD-PARTY coding agent (a harnesses.yml entry — Claude Code, Codex, OpenCode, Pi ...) inside a workspace/sandbox it provisions, with the agent's auth wired in (your own account or API key), so you start an agent session rather than an empty box. Distinct from built-in-agent (a FIRST-PARTY agent the vendor ships) and from harnesses[] (which records that a harness CAN target the product, not that the product runs it for you).
Supported

Data 0/4

First-party databasePlatform-provided managed database.
Not supported
Database branchingCopy-on-write branch of a DATABASE (schema + data) as a dev-lifecycle primitive — branch your data like code, usually instant via a metadata operation. Distinct from snapshots-forks (forks a running compute INSTANCE / VM state) and from preview-environments (a full per-PR environment that may USE a DB branch). For a data product a CoW branch maps HERE, not to snapshots-forks.
Not supported
Vector searchFirst-class storage, indexing, and similarity search of vector embeddings — a native vector type/index or a managed vector DB. The data-layer primitive for RAG / semantic retrieval.
Not supported
Ephemeral instant DB (no-signup)Provision a working, usable instance via a single command / HTTP call with NO account, signup, or card — typically time-boxed (expires unless claimed). A zero-onboarding path an agent can hit directly.
Not supported

Platform & operations 0/6

Scheduled tasksCron / scheduled job primitive.
Not supported
Durable workflowsDurable execution / long-running workflow primitive.
Not supported
Preview environmentsA full EPHEMERAL environment spun up per PR / branch — compute + addons + (often) a DB branch — torn down on merge. More than preview-urls (which is just a shareable URL for one deploy).
Not supported
Built-in observabilityFirst-party metrics / logs / tracing / APM / profiling included in the platform (no third-party stack required to see what a workload is doing).
Partially supported
Managed CI/CD runnersPlatform-hosted, drop-in CI/CD runner VMs (GitHub Actions / GitLab), typically faster and cheaper than the CI vendor's own hosted runners, billed per runner-minute; isolated + ephemeral per job. Distinct from git-deploy (push-to-deploy of an APP) and scheduled-tasks (cron) — this is managed CI COMPUTE you point your existing pipelines at.
Not supported
Project template marketplaceA marketplace / gallery of prebuilt PROJECT STARTER templates (apps or websites) a user clones or launches a new project from and then customises — the "start from a template" surface of a builder / PaaS. Distinct from sandbox-templates (a COMPUTE base IMAGE you fork runtime INSTANCES from — Dockerfile / OCI), from app-builder (the prompt-to-app GENERATION surface — a product can have both), and from one-click OSS-app catalogues / helm-addon-marketplace (deploy a FINISHED app as-is, not a starter you build on).
Not supported

Organisation & security 1/9

Built-in authPlatform-provided authentication / IAM for workloads.
Not supported
SSO / SAMLEnterprise single sign-on.
Partially supported
Secrets managementFirst-class secrets storage / injection.
Partially supported
TeamsMulti-user team accounts.
Not supported
SharingShare a running workload/resource via link (optionally gated).
Partially supported
BYOCRuns inside the customer's own cloud account.
Not supported
Deploy into customers' VPCsA SaaS vendor uses the platform to deploy and operate ITS software inside ITS CUSTOMERS' cloud accounts / VPCs (nested or "customer BYOC"), managed from the vendor's control plane. Distinct from byoc (your own workloads in your own cloud account).
Not supported
Workload identityThe platform gives each workload its own verifiable identity (OIDC token, SPIFFE SVID, cloud IAM federation) that it exchanges for short-lived credentials, so no long-lived static secret is stored or injected. Distinct from secrets-management (stores / injects static secrets) and credential-injection-proxy (swaps real secrets in on the wire).
Not supported
Self-host / OSS coreOpen-source core that can be self-hosted.
Supported

Proposed, not verified

Capabilities the scan saw but the registry does not track yet. A key is admitted only once two distinct products exhibit it. These are not scored.

  • Portable self-contained VM artifact (.smolmachine)portable-vm-artifact

    “Pack a machine, however you set it up, into a single `.smolmachine` file. Push it to any OCI registry, or run it as a self-contained executable that boots in under 200 ms with nothing to install.” github.com

04 Agent readiness Pre-login surface · counts, not a grade

Can an agent read it?

parse-ability · docs, metadata, machine-readable surfaces

10/11

10 full · 0 partial · 91% of applicable checks

  • llms.txt
    Supported
  • llms-full.txt
    Not supported
  • robots.txt AI policy
    Supported
  • JSON-LD
    Supported
  • Sitemap
    Supported
  • Meta tags
    Supported
  • Markdown negotiation
    Supported
  • Content efficiency
    Supported
  • Docs discoverable
    Supported
  • Machine-readable pricing
    Supported
  • No anti-bot wall
    Supported

Can an agent drive it?

act-ability · APIs, SDKs, MCP, credentials, webhooks

9/11

7 full · 2 partial · 82% of applicable checks

  • Public API
    Supported
  • OpenAPI spec
    Supported
  • MCP server
    Not supported
  • SDK packages
    Supported
  • Auth documented
    Supported
  • Self-serve credentials
    Supported
  • Webhooks
    Not supported
  • CLI tool
    Supported
  • Error model
    Supported
  • Rate limits documented
    Partially supported
  • Agent config files
    Partially supported

05 Coding harnesses Which agents and IDEs are documented to run here

Advertised integrations 1

  • Codex CLI OpenAI
    Supported

    Advertised via a prebuilt registry base machine (a ready-to-run .smolmachine), not a bespoke integration.

Plausible compatibility 0

Derived, not stored: the product passes SSH access, so any CLI coding agent is installable inside it. This is plausible compatibility, not a supported integration.

No general shell access documented, so nothing is derived. Absence is not unsupported.

06 Compliance & regions Standards held, with ordinal rigor; never a score

Certifications held 2

  • CCPA
    self-attestedhostedSelf-attested; hosted service only.
  • GDPR
    self-attestedhostedSelf-attested in the privacy policy (rights honoured); no third-party report. Hosted service only — the OSS engine you run yourself is outside this scope.

Regions —

Regions are not disclosed on the public surface.

Country-level disclosure: Google Cloud US regions and data processed in United States. Exact hosted regions and placement choices not public; no multi-region availability inferred. Self-host placement is operator-defined.

07 Open source Apache-2.0 · fetched by machine, not quoted from marketing

Licence & repository

Licence
Apache-2.0OSI
Primary language
Rust
Stars
6,699
Forks
326
Created
18 Dec 2025
Archived
No

Activity

Last commit
12 Oct 2026
Latest release
v1.27.1 · 12 Oct 2026
Issues open / closed
31 / 246 · 89% closed

8 recent releases retained; latest v1.27.1, two releases published on 2026-10-12 and two on 2026-10-10.

Fetched via gh on 12 Oct 2026.

Self-hosting

Methods
binarysource-build
You operate
—

Apache-2.0 engine is free plus operator hardware/infra. Linux x86_64/aarch64 needs KVM; macOS needs Hypervisor.framework entitlements; native Windows x86_64 needs WHP. Standalone engine/CLI/serve API has no production fleet scheduler, placement, failover, tenant management, billing or managed durability. GPU is local/self-host only: Vulkan host stack or NVIDIA driver for CUDA remoting; GPU sharing is not hardware-partitioned multi-tenant isolation. Branch/checkpoint limits depend on host, runtime version and attached devices; Windows branches require --freeze-source.

Documentation signals 8/8

  • SupportedQuickstart
  • SupportedAPI reference
  • SupportedSelf-host guide
  • SupportedChangelog
  • SupportedOpenAPI
  • Supportedllms.txt
  • SupportedExamples
  • SupportedArchitecture doc

08 Company & presence Facts only, not scored

Company

Headquarters
unknown
Founded
unknown
Team size
unknown
Hiring
unknown

Activity

Last release
v1.27.1 (2026-10-12T06:38:07Z) github.com
Last blog post
Giving AI an undo button — September 24, 2026; next posts GPU remoting and Kubernetes dated July 14, 2026. smolmachines.com

Presence 5

Links found on the public surface scanned; not an exhaustive search.

09 Sources & method How this entry was produced

Public surface only

Everything here was read from smolmachines.com's unauthenticated pages, docs, pricing and repository on 12 Oct 2026. Nothing behind a login was used.

Statuses, not scores

Capabilities are pass, partial or fail against a written rubric (features v21). “Not assessed” means the scan predates the key.

Confidence is separate

Each fact carries its own confidence. Low-confidence facts are shown, never hidden, so you can weigh them.

Schema
scan v5
Features registry
v21
Keys tracked today
61
Assessed on this entry
61
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where do i run this.

An independent spec sheet for places to run code, and the code your agents write. Facts come from each product's public pages; every capability is a count, never a grade.

Verify

Pages change; so do prices. Verify on the vendor's site before you commit; every product page shows when it was read.

Where Do I Run This © 2026counts, not grades · public pages only