Sandboxes - Durable machines for code that has to run

Your sandbox should be as durable as any other function, and just as easy to set up. When it fails, or has to wait, you don't lose the run.

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Use cases

Durable machinesfor every agent.

A sandbox is a step. It retries, it shows up on the trace, and the same flow control you already use applies to the run.

inngest/analyse-data.ts

// One machine per run. Commands are steps.
const sandbox = await step.sandbox.create(
  "create-sandbox",
  {
    name: `analyst-${runId}`,
    vcpu: 1,
    memoryMb: 1024,
  },
);
 
const result = await sandbox.commands.run(
  "run-code",
  ["python3", "-c", code],
);

Code interpreter

Run AI-generated code

If you ask a question, and your agent writes Python to answer it, that script needs a machine. Each question gets its own sandbox: upload the file, run the code, and the output comes back as the next step.

Read the docs

inngest/score-code.ts

// Run each case sandboxed. Score after.
const result = await sandbox.commands.run(
  `case-${i}`,
  'printf %s "$INPUT" | python3 -c "$CODE"',
  {
    environment: {
      CODE: code,
      INPUT: test.stdin,
    },
    timeout: "5s",
  },
);
 
defer("score", {
  function: passRate,
  data: { code, cases },
  experiment: experimentRef,
});

Evals

Score generated code

A new prompt only counts if the code it writes still passes. Run each case in a sandbox, then score in the background so the result is credited to the prompt that wrote it.

Read the docs

inngest/process-dataset.ts

// Install once, snapshot, clone per file.
await builder.commands.run(
  "install",
  "pip install --quiet duckdb",
  { timeout: "5m" },
);
 
const environment = await builder.snapshot(
  "snapshot-environment",
);
 
const worker = await environment.clone(
  `clone-${i}`,
  { name: `dataset-${runId}-${i}` },
);

Custom environments

Heavy jobs, off your servers

A DuckDB pass, a media batch, or a build will swamp the server handling requests. Install the tools once, snapshot the environment, and clone a worker per file. Each file retries on its own.

Read the docs

Why Inngest