Vercel has cut the latency of routing traffic to public Sandbox domains by roughly eighteenfold, shifting resolution from a single centralized store to the nearest regional replica for domains created via the sandbox.domain() SDK. Median lookup time fell from 62 milliseconds to 3.4 milliseconds, which means incoming HTTP requests should reach the live sandbox process with measurably less delay. The change matters for agent and preview workflows that rely on quick public URLs, including Cursor Cloud Agents that can already execute inside Vercel Sandbox through Self-Hosted Machines APIs on Enterprise plans. Operators should treat the figure as a vendor-reported median on domain lookup only; end-to-end request latency and regional gains may vary once application code, cold starts, and upstream networks are included.
Requests to Vercel Sandbox public domains are now routed 18x faster. Median domain lookup latency dropped from 62ms to 3.4ms.
Key takeaway
Regional replica resolution for sandbox.domain() URLs collapses median lookup latency from 62ms to 3.4ms, tightening the public path into live sandboxes.
What happened
Vercel reported that requests to Vercel Sandbox public domains are now routed 18x faster globally. Domains created with the sandbox.domain() SDK call are now resolved from the nearest regional replica, instead of a single centralized store, per the company's changelog.
Vercel states median domain lookup latency dropped from 62ms to 3.4ms and that incoming requests reach the process running in the sandbox with less latency. A related changelog notes Cursor Cloud Agents can run in Vercel Sandbox via Self-Hosted Machines APIs on Cursor Enterprise plans.
Evidence
Vercel Sandbox public domain routing is 18x faster with median lookup latency falling from 62ms to 3.4ms
Vercel AI · attributed
Requests to Vercel Sandbox public domains are now routed 18x faster. Median domain lookup latency dropped from 62ms to 3.4ms.
sandbox.domain() domains resolve from the nearest regional replica instead of a centralized store
Vercel AI · attributed
Domains created with the sandbox.domain() SDK call are now resolved from the nearest regional replica, instead of a single centralized store.
Cursor Cloud Agents can run in Vercel Sandbox using Self-Hosted Machines APIs on Enterprise plans
Vercel AI · attributed
Cursor Cloud Agents can now run in Vercel Sandbox instead of Cursor's hosted machines. Self-Hosted Machines requires a Cursor Enterprise plan.
Why it matters
Faster public routing reduces friction for agent and preview workloads that depend on sandbox URLs, including enterprise Cursor agents hosted via Self-Hosted Machines.
Limits and uncertainties
The packet reports median domain lookup latency only; it does not quantify end-to-end request latency or per-region variance.
Running Cursor Cloud Agents in Vercel Sandbox via Self-Hosted Machines requires a Cursor Enterprise plan.
Practical implications
Teams using sandbox.domain() for previews or agents should retest latency-sensitive flows after the routing change.
Cursor Enterprise customers evaluating Self-Hosted Machines should factor improved sandbox URL resolution into sandbox adoption decisions.
