Agent Sandboxes

The fastest agent sandboxes with real isolation.

A 50ms cold boot on KVM, hosted in the EU.

Speed

Boot in 50ms, fork fifty in parallel.

A full VM boots in 50ms and resumes from sleep in 8ms. Forking a running machine takes milliseconds, so you can run fifty in parallel before another platform has finished provisioning one.

cold boot · 1s window
0ms250ms500ms750ms1000ms
boxd
50ms · cold
Daytona
27ms · template
E2B
~500ms · cold
Modal
~1-2s · cold
boxd
cold boot
template resume

Real isolation

Every sandbox runs its own kernel.

Every sandbox is a real KVM virtual machine with its own kernel. Agents get root inside it and can modify anything, but they cannot reach the host or other sandboxes. Container sandboxes share a kernel across tenants, so one kernel bug compromises every sandbox on the host.

isolation model
container sandbox
a
b
c
shared kernel
host
CVE in a reaches b · c · host
boxd
a
b
c
kvm
kvm
kvm
host
CVE in a stops at own wall · contained

Sovereignty

Host it in Europe, or host it yourself.

boxd infrastructure runs in European data centers, beyond reach of US subpoenas. You can also run the same binary on your own metal, where nothing leaves your network at all.

deployment paths
boxd EUmanaged
Roubaix · FR
GDPR by default
48ms · cold boot
your clusterself-hosted
your datacenter
one rust binary
48ms · cold boot
same ssh api
ssh boxd.sh · ssh your-domain.com
Same API. Same specs. Your choice of where it runs.
50ms
cold boot
8ms
resume from sleep
0
shared kernels

boxd vs. the other agent sandboxes

boxdE2BModalDaytona
Cold boot50ms~500ms~2s~27ms (template)
IsolationKVM (own kernel)FirecrackergVisor (shared kernel)Container
Persistent stateYesNoNoPartial
Self-hostableYesNoNoYes
InterfaceSSHSDKSDKCLI + SDK

Related use cases

Stop running agents on slow infrastructure.

Talk to us about your team's setup, or boot a sandbox yourself with one SSH command.

read the docs · see pricing · ssh boxd.sh