Introducing Deno Sandbox

Deno Sandbox gives you lightweight Linux microVMs (running in the Deno Deploy cloud) to run untrusted code with defense-in-depth security. You create or programmatically via our JavaScript or Python SDKs, and they boot in under a second. You can also interact with them via SSH, HTTP, or even open a VS Code window directly into the sandbox.

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But there is more. In Deno Sandbox, secrets never enter the environment. Code sees only a placeholder:

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The real key materializes only when the sandbox makes an outbound request to an approved host. If prompt-injected code tries to exfiltrate that placeholder to evil.com? Useless.