Function random

Returns a deterministic pseudo-random number between 0 and 1. The value is derived from the current execution counter, so it produces the same result on every replay of the workflow at this execution point.

Use this instead of Math.random() inside workflow functions. Math.random() is non-deterministic and would break replay correctness.

Examples

import { Durable } from '@hotmeshio/hotmesh';

// Generate a deterministic unique suffix
export async function uniqueWorkflow(): Promise<string> {
  const suffix = Math.floor(Durable.workflow.random() * 10000);
  return `item-${suffix}`;
}
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// A/B test routing (deterministic per workflow execution)
export async function experimentWorkflow(userId: string): Promise<string> {
  const { variantA, variantB } = Durable.workflow.proxyActivities<typeof activities>();

  if (Durable.workflow.random() < 0.5) {
    return await variantA(userId);
  } else {
    return await variantB(userId);
  }
}
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